[1] Wild type Enterobacterales are categorised as susceptible to aminopenicillins. 
Some countries prefer to categorise wild-type isolates of E. coli and P. mirabilis as "Susceptible, increased exposure". When this is the case, use the MIC breakpoint S ≤ 0.5 mg/L and the corresponding zone diameter breakpoint S ≥ 50 mm.
[A] Wild type Enterobacterales are categorised as susceptible to aminopenicillins. 
Some countries prefer to categorise wild-type isolates of E. coli and P. mirabilis as "Susceptible, increased exposure". When this is the case, use the MIC breakpoint S ≤ 0.5 mg/L and the corresponding zone diameter breakpoint S ≥ 50 mm. | [B] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars.
[1] Wild type Enterobacterales are categorised as susceptible to aminopenicillins. 
Some countries prefer to categorise wild-type isolates of E. coli and P. mirabilis as "Susceptible, increased exposure". When this is the case, use the MIC breakpoint S ≤ 0.5 mg/L and the corresponding zone diameter breakpoint S ≥ 50 mm. | [2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[A] Wild type Enterobacterales are categorised as susceptible to aminopenicillins. 
Some countries prefer to categorise wild-type isolates of E. coli and P. mirabilis as "Susceptible, increased exposure". When this is the case, use the MIC breakpoint S ≤ 0.5 mg/L and the corresponding zone diameter breakpoint S ≥ 50 mm. | [B] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars.
[1] Wild type Enterobacterales are categorised as susceptible to aminopenicillins. 
Some countries prefer to categorise wild-type isolates of E. coli and P. mirabilis as "Susceptible, increased exposure". When this is the case, use the MIC breakpoint S ≤ 0.5 mg/L and the corresponding zone diameter breakpoint S ≥ 50 mm.
[C] Susceptibility inferred from ampicillin.
[1] Wild type Enterobacterales are categorised as susceptible to aminopenicillins. 
Some countries prefer to categorise wild-type isolates of E. coli and P. mirabilis as "Susceptible, increased exposure". When this is the case, use the MIC breakpoint S ≤ 0.5 mg/L and the corresponding zone diameter breakpoint S ≥ 50 mm. | [3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Wild type Enterobacterales are categorised as susceptible to aminopenicillins. 
Some countries prefer to categorise wild-type isolates of E. coli and P. mirabilis as "Susceptible, increased exposure". When this is the case, use the MIC breakpoint S ≤ 0.5 mg/L and the corresponding zone diameter breakpoint S ≥ 50 mm. | [B] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars.
[1] Wild type Enterobacterales are categorised as susceptible to aminopenicillins. 
Some countries prefer to categorise wild-type isolates of E. coli and P. mirabilis as "Susceptible, increased exposure". When this is the case, use the MIC breakpoint S ≤ 0.5 mg/L and the corresponding zone diameter breakpoint S ≥ 50 mm. | [3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Wild type Enterobacterales are categorised as susceptible to aminopenicillins. 
Some countries prefer to categorise wild-type isolates of E. coli and P. mirabilis as "Susceptible, increased exposure". When this is the case, use the MIC breakpoint S ≤ 0.5 mg/L and the corresponding zone diameter breakpoint S ≥ 50 mm. | [B] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[5] Breakpoints still under consideration.
[5] Breakpoints still under consideration.
[6] Agar dilution is the reference method for mecillinam MIC determination.
[D] Ignore isolated colonies within the inhibition zone for E. coli.
[2] The cefoxitin ECOFF (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[3] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[2] The intrinsically low activity of imipenem against Morganella morganii,Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[2] The intrinsically low activity of imipenem against Morganella morganii,Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[3] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[A] Tests with a ciprofloxacin 5 µg disk will not reliably detect low-level resistance in Salmonella spp. To screen for ciprofloxacin resistance in Salmonella spp., use the pefloxacin 5 µg disk. See Note | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[B]  | [B] Susceptibility of Salmonella spp. to ciprofloxacin can be inferred from pefloxacin disk diffusion susceptibility. | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [3] For other Enterobacterales, the activity of tigecycline varies from insufficient in Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see http://www.eucast.org/guidance_documents/.
[A] For other Enterobacterales, the activity of tigecycline varies from insufficient in Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see http://www.eucast.org/guidance_documents/. | [B] Zone diameter breakpoints validated for E. coli only. For C.koseri, use an MIC method.
[1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[2] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[C] Zone diameter breakpoints apply to E. coli only. For other Enterobacterales, use an MIC method. | [D] Ignore isolated colonies within the inhibition zone (see pictures below).
[2] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[C] Zone diameter breakpoints apply to E. coli only. For other Enterobacterales, use an MIC method. | [D] Ignore isolated colonies within the inhibition zone (see pictures below).
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[1] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Isolates showing any sign of inhibition zone ≥ 16 mm should be reported susceptible and growth within the inhibition zone should be ignored. The density of growth within the zone may vary from a fine haze to substantial growth (see pictures below). | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[4] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [3] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[3/A] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[3] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[3/A] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [3] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[3/A] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[3] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[3/A] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[3] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[3/A] Susceptibility to ampicillin, amoxicillin and piperacillin with and without beta-lactamase inhibitor can be inferred from ampicillin.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Susceptibility of ciprofloxacin and levofloxacin can be inferred from the norfloxacin susceptibility.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[3] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[B] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Vancomycin susceptible enterococci exhibit sharp zone edges and do not exhibit colonies in the inhibition zone. Examine zone edges with transmitted light (plate held up to light). If the zone edge is fuzzy, colonies grow within the zone  or if you are uncertain, then perform confirmatory testing with PCR or report resistant (see pictures below) even if the zone diameter is ≥ 12 mm. Isolates must not be reported susceptible before 24 h incubation.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] For more information, see http://www.eucast.org/guidance_documents/.
[1] For more information, see http://www.eucast.org/guidance_documents/.
[2] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[A] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[2] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility. | [2] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility. | [2] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to norfloxacin can be reported susceptible to levofloxacin and moxifloxacin. Isolates categorised as non-susceptible should be tested for susceptibility to individual agents.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[3] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Isolates susceptible to linezolid can be reported susceptible to tedizolid. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Isolates susceptible to linezolid can be reported susceptible to tedizolid. For isolates resistant to linezolid, perform an MIC test. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Daptomycin MICs must be determined in the presence of Ca (50 mg/L in the medium for broth dilution methods; agar dilution methods have not been validated).  Follow the manufacturer's instructions for commercial systems. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Use an MIC method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [3] For breakpoints and dosing in pneumonia, see table of dosages.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [3] For breakpoints and dosing in pneumonia, see table of dosages.
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [4] Susceptibility inferred from ampicillin (MIC or zone diameter).
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter).
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [4] Susceptibility inferred from ampicillin (MIC or zone diameter).
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter).
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [C] Perform an MIC or infer susceptibility from the ampicillin 2 µg disk diffusion test with ampicillin breakpoints S≥22, R<19 mm.
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [4] Susceptibility inferred from ampicillin (MIC or zone diameter).
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter).
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [C] Perform an MIC or infer susceptibility from the ampicillin 2 µg disk diffusion test with ampicillin breakpoints S≥22, R<19 mm.
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [4] Susceptibility inferred from ampicillin (MIC or zone diameter).
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter).
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [4] Susceptibility inferred from ampicillin (MIC or zone diameter).
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter).
[1] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[D] For interpretation of the oxacillin disk screen, see flow chart below.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation.
[2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[3] Meropenem is the only carbapenem used for meningitis.
[A] The oxacillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥20 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing. When the screen is positive (inhibition zone <20 mm), see flow chart below for interpretation. | [B] For use in meningitis determine the meropenem MIC. | [3] Meropenem is the only carbapenem used for meningitis.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to norfloxacin can be reported susceptible to levofloxacin and moxifloxacin. Isolates categorised as non-susceptible should be tested for susceptibility to individual agents.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents.
[1] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[1] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[1] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[1] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[A] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[A] Perform an MIC test.
[1/A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [4] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation. | [C] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation. | [D] Susceptibility can be inferred from ampicillin. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation. | [D] Susceptibility can be inferred from ampicillin. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[6] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation. | [B] ATU relevant only if the benzylpenicillin 1 unit disk screen is positive (inhibition zone <12 mm).
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation. | [B] ATU relevant only if the benzylpenicillin 1 unit disk screen is positive (inhibition zone <12 mm).
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation.
[2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation. | [2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation. | [B] ATU relevant only if the benzylpenicillin 1 unit disk screen is positive (inhibition zone <12 mm). | [2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all beta-lactam agents for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below for interpretation. | [2] Not for meningitis (meropenem is the only carbapenem used for meningitis).
[3] Meropenem is the only carbapenem used for meningitis.
[C] For use in meningitis determine the meropenem MIC value. | [3] Meropenem is the only carbapenem used for meningitis.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to nalidixic acid can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as non-susceptible may have fluoroquinolone resistance and should be tested against the appropriate agent.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to nalidixic acid can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as non-susceptible may have fluoroquinolone resistance and should be tested against the appropriate agent.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Breakpoints relate to topical use only.
[A] Breakpoints relate to topical use only.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Always test for beta-lactamase. If positive, report resistant to benzylpenicillin, ampicillin and amoxicillin. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase. The susceptibility of beta-lactamase negative isolates to ampicillin and amoxicillin can be inferred from benzylpenicillin.
[1] Always test for beta-lactamase. If positive, report resistant to benzylpenicillin, ampicillin and amoxicillin. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase. The susceptibility of beta-lactamase negative isolates to ampicillin and amoxicillin can be inferred from benzylpenicillin.
[1] Always test for beta-lactamase. If positive, report resistant to benzylpenicillin, ampicillin and amoxicillin. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase. The susceptibility of beta-lactamase negative isolates to ampicillin and amoxicillin can be inferred from benzylpenicillin.
[1] Always test for beta-lactamase. If positive, report resistant to benzylpenicillin, ampicillin and amoxicillin. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase. The susceptibility of beta-lactamase negative isolates to ampicillin and amoxicillin can be inferred from benzylpenicillin.
[1] Azithromycin is always used in conjunction with another effective agent. For testing purposes with the aim of detecting acquired resistance mechanisms, the ECOFF is 1 mg/L.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Breakpoints apply only to use in the prophylaxis of meningococcal disease.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] For prophylaxis of meningitis only (refer to national guidelines).
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections with vancomycin. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[4] Fidaxomicin breakpoints and ECOFF have not been set because the available data show major variation in MIC distribution between studies.
[5] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections with metronidazole. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs), which distinguish wild-type isolates from those with reduced susceptibility.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs), which distinguish wild-type isolates from those with reduced susceptibility.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs), which distinguish wild-type isolates from those with reduced susceptibility.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs), which distinguish wild-type isolates from those with reduced susceptibility.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs), which distinguish wild-type isolates from those with reduced susceptibility.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs), which distinguish wild-type isolates from those with reduced susceptibility.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[1] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[B] Isolates categorised as susceptible to nalidixic acid can be reported susceptible to ciprofloxacin and levofloxacin. Isolates categorised as non-susceptible may have fluoroquinolone resistance and should be tested against the appropriate agent.
[A] Susceptibility inferred from tetracycline screen test.
[A] Susceptibility inferred from tetracycline screen test.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Tetracycline can be used to determine susceptibility to doxycycline.
[1] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Non-wild typeisolates were not available when developing the disk diffusion method.
[1] Infer susceptibility from ampicillin susceptibility.
[A] Infer susceptibility from ampicillin susceptibility.
[A] Susceptibility can be inferred from norfloxacin susceptibility. See Note
[1] Susceptibility can be inferred from ciprofloxacin susceptibility.
[B] Susceptibility can be inferred from ciprofloxacin or norfloxacin susceptibility. See Note
[C]  | [C] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance.
[A] Non-wild type isolates were not available when developing the disk diffusion method.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[3] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[B] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline, but some resistant to tetracycline may be susceptible to doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline, but some resistant to tetracycline may be susceptible to doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Read the obvious zone edge and disregard haze or growth within the inhibition zone (see pictures below). | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Breakpointss apply only to tests performed on Middlebrook 7H11/7H10 medium. Comparability of tests performed by other media has not been established.
[1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. Breakpoints for oral administration are relevant for uncomplicated urinary tract infections only. Breakpoints for other infections are under review.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. Breakpoints for oral administration are relevant for uncomplicated urinary tract infections only. Breakpoints for other infections are under review.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. Breakpoints for oral administration are relevant for uncomplicated urinary tract infections only. Breakpoints for other infections are under review.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. Breakpoints for oral administration are relevant for uncomplicated urinary tract infections only. Breakpoints for other infections are under review.
[1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. Breakpoints for oral administration are relevant for uncomplicated urinary tract infections only. Breakpoints for other infections are under review.
[B] Susceptibility inferred from ampicillin. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. Breakpoints for oral administration are relevant for uncomplicated urinary tract infections only. Breakpoints for other infections are under review.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. Breakpoints for oral administration are relevant for uncomplicated urinary tract infections only. Breakpoints for other infections are under review.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. Breakpoints for oral administration are relevant for uncomplicated urinary tract infections only. Breakpoints for other infections are under review.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[5] Breakpoints still under consideration.
[C] Breakpoints still under consideration.
[6] Agar dilution is the reference method for mecillinam MIC determination.
[D] Ignore isolated colonies within the inhibition zone.
[2] The cefoxitin ECOFF (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[3] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[5] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [4] See table of dosages for dosing for different indications.
[4] See table of dosages for dosing for different indications.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[3] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[A] Tests with a ciprofloxacin 5 µg disk will not reliably detect low-level resistance in Salmonella spp. To screen for ciprofloxacin resistance in Salmonella spp., use the pefloxacin 5 µg disk. See Note | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[2/C] The pefloxacin 5 µg breakpoint used to screen for clinical fluoroquinolone resistance in Salmonella spp., can also be used to detect fluoroquinolone resistance mechanisms in other Enterobacterales such as E. coli, K. pneumoniae and Shigella spp. | [B]  | [B] Susceptibility of Salmonella spp. to ciprofloxacin can be inferred from pefloxacin disk diffusion susceptibility. | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[D] A disk diffusion test is not yet developed. Perform an MIC test.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [3] For other Enterobacterales, the activity of tigecycline varies from insufficient in Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see http://www.eucast.org/guidance_documents/.
[A] For other Enterobacterales, the activity of tigecycline varies from insufficient in Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see http://www.eucast.org/guidance_documents/. | [B] Zone diameter breakpoints validated for E. coli only. For C. koseri, use an MIC method.
[1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[2] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[C] Zone diameter breakpoints apply to E. coli only. For other Enterobacterales, use an MIC method. | [D] Ignore isolated colonies within the inhibition zone (see pictures below).
[2] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[C] Zone diameter breakpoints apply to E. coli only. For other Enterobacterales, use an MIC method. | [D] Ignore isolated colonies within the inhibition zone (see pictures below).
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[3] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [2] See table of dosages for dosing for different indications.
[2] See table of dosages for dosing for different indications.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. Oral administration is relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. Oral administration is relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. Oral administration is relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. Oral administration is relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. Oral administration is relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. Oral administration is relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. Oral administration is relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. Oral administration is relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Susceptibility of ciprofloxacin and levofloxacin can be inferred from the norfloxacin susceptibility.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[3] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[B] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Vancomycin susceptible enterococci exhibit sharp zone edges and do not exhibit colonies in the inhibition zone. Examine zone edges with transmitted light (plate held up to light). If the zone edge is fuzzy, colonies grow within the zone  or if you are uncertain, then perform confirmatory testing with PCR or report resistant (see pictures below) even if the zone diameter is ≥ 12 mm. Isolates must not be reported susceptible before 24 h incubation.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] For more information, see http://www.eucast.org/guidance_documents/.
[1] For more information, see http://www.eucast.org/guidance_documents/.
[2] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[A] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[2] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[2] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[2] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[2] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] Streptococcus groups A, B, C and G do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] A disk diffusion test is not yet developed. Perform an MIC test.
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C]  | [C] Isolates categorised as susceptible to norfloxacin can be reported susceptible to moxifloxacin and as "susceptible increased exposure" (I) to levofloxacin. Isolates categorised as non-susceptible should be tested for susceptibility to individual agents.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[3] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Isolates susceptible to linezolid can be reported susceptible to tedizolid. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Isolates susceptible to linezolid can be reported susceptible to tedizolid. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Daptomycin MICs must be determined in the presence of Ca (50 mg/L in the medium for broth dilution methods; agar dilution methods have not been validated).  Follow the manufacturer's instructions for commercial systems. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Use an MIC method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [3] For breakpoints and dosing in pneumonia, see table of dosages.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [3] For breakpoints and dosing in pneumonia, see table of dosages.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [5] Susceptibility inferred from ampicillin (MIC or zone diameter). | [4] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter). | [4] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [5] Susceptibility inferred from ampicillin (MIC or zone diameter).
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter).
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Perform an MIC or infer susceptibility from the ampicillin 2 µg disk diffusion test with ampicillin breakpoints S≥22, R<19 mm.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [5] Susceptibility inferred from ampicillin (MIC or zone diameter). | [4] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter). | [4] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [6] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [4] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Perform an MIC or infer susceptibility from the ampicillin 2 µg disk diffusion test with ampicillin breakpoints S≥22, R<19 mm. | [4] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [5] Susceptibility inferred from ampicillin (MIC or zone diameter).
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter).
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [5] Susceptibility inferred from ampicillin (MIC or zone diameter). | [4] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (MIC or zone diameter). | [4] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[D] For interpretation of the oxacillin disk screen, see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[3] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3/B] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] For use in meningitis determine the meropenem MIC.
[3] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3/B] Streptococcus pneumoniae do not produce beta-lactamase. The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to norfloxacin can be reported susceptible to moxifloxacin and as "susceptible increased exposure" (I) to levofloxacin. Isolates categorised as non-susceptible should be tested for susceptibility to individual agents.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents.
[1] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[1] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[1] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[1] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as susceptible can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as non-susceptible should be tested for susceptibility to individual agents. | [B] For isolates susceptible to benzylpenicillin, susceptibility can be inferred from benzylpenicillin or ampicillin. For isolates resistant to benzylpenicillin, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[A] Benzylpenicillin 1 unit can be used to screen for beta-lactam resistance in viridans group streptococci. See Note A on penicillins.
[A] A disk diffusion test is not yet developed. Perform an MIC test.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[A] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[1/A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [4] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [D] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [E] Susceptibility can be inferred from ampicillin. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[6] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] See table of dosages for dosing for different indications.
[2] See table of dosages for dosing for different indications.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [D] For benzylpenicillin 1 unit disk screen positive isolates (inhibition zone <12 mm), determine the MIC for meropenem.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to nalidixic acid can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as non-susceptible may have fluoroquinolone resistance and should be tested against the appropriate agent.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to nalidixic acid can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as non-susceptible may have fluoroquinolone resistance and should be tested against the appropriate agent.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Breakpoints relate to topical use only.
[A] Breakpoints relate to topical use only.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Azithromycin is always used in conjunction with another effective agent. For testing purposes with the aim of detecting acquired resistance mechanisms, the ECOFF is 1 mg/L.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Breakpoints apply only to use in the prophylaxis of meningococcal disease.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] See table of dosages.
[2] For prophylaxis of meningitis only (refer to national guidelines).
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections with vancomycin. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[4] Fidaxomicin breakpoints and ECOFF have not been set because the available data show major variation in MIC distribution between studies.
[5] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections with metronidazole. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[1] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[B] Isolates categorised as susceptible to nalidixic acid can be reported susceptible to ciprofloxacin and levofloxacin. Isolates categorised as non-susceptible may have fluoroquinolone resistance and should be tested against the appropriate agent.
[A] Susceptibility inferred from tetracycline screen test.
[A] Susceptibility inferred from tetracycline screen test.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Tetracycline can be used to determine susceptibility to doxycycline.
[1] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Non-wild typeisolates were not available when developing the disk diffusion method.
[1] Inducible clindamycin resistance may occur in Corynebacteria. This can be detected by antagonism of clindamycin activity by a macrolide agent. The clinical significance is unknown. There is currently no recommendation for testing.
[1] Inducible clindamycin resistance may occur in Corynebacteria. This can be detected by antagonism of clindamycin activity by a macrolide agent. The clinical significance is unknown. There is currently no recommendation for testing.
[1] Infer susceptibility from ampicillin susceptibility.
[A] Infer susceptibility from ampicillin susceptibility.
[A] Susceptibility can be inferred from norfloxacin susceptibility. See Note
[1] Susceptibility can be inferred from ciprofloxacin susceptibility.
[B] Susceptibility can be inferred from ciprofloxacin or norfloxacin susceptibility. See Note
[C]  | [C] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance.
[A] Non-wild type isolates were not available when developing the disk diffusion method.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[3] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[B] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline, but some resistant to tetracycline may be susceptible to doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline, but some resistant to tetracycline may be susceptible to doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Read the obvious zone edge and disregard haze or growth within the inhibition zone (see pictures below). | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Susceptibility inferred from tetracycline disk diffusion screen test.
[A] Susceptibility inferred from tetracycline disk diffusion screen test.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Breakpoints were determined on MICs performed on Middlebrook 7H11/7H10 medium. The comparability of tests performed by other media has not been established. There is ongoing work to review breakpoints using the EUCAST reference method (described above).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[2] Breakpoints for nasal decontamination S ≤1, R >256 mg/L (S ≥30, R <18 mm for the mupirocin 200 µg disk). Isolates in the I category are associated with short term suppression (useful preoperatively) but, unlike fully susceptible isolates, long term eradication rates are low.
ND = No ECOFF available.
[2] Breakpoints for nasal decontamination S ≤1, R >256 mg/L (S ≥30, R <18 mm for the mupirocin 200 µg disk). Isolates in the I category are associated with short term suppression (useful preoperatively) but, unlike fully susceptible isolates, long term eradication rates are low.
ND = No ECOFF available.
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[B] Susceptibility inferred from ampicillin. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[C] Ignore isolated colonies within the inhibition zone.
[5] Agar dilution is the reference method for mecillinam MIC determination.
[C] Ignore isolated colonies within the inhibition zone.
[2] Isolates susceptible to cefadroxil and/or cefalexin can be reported "susceptible, increased exposure” (I) to cefazolin.
[A] Isolates susceptible to cefadroxil and/or cefalexin can be reported "susceptible, increased exposure” (I) to cefazolin.
[3] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see http://www.eucast.org/guidance_documents/.
[4] The cefoxitin ECOFF (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[4] The cefoxitin ECOFF (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[5] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[7] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [6] See table of dosages for dosing for different indications.
[6] See table of dosages for dosing for different indications.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[3] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[A] Tests with a ciprofloxacin 5 µg disk will not reliably detect low-level resistance in Salmonella spp. To screen for ciprofloxacin resistance in Salmonella spp., use the pefloxacin 5 µg disk. See Note | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[2/C] The pefloxacin 5 µg breakpoint used to screen for clinical fluoroquinolone resistance in Salmonella spp., can also be used to detect fluoroquinolone resistance mechanisms in other Enterobacterales such as E. coli, K. pneumoniae and Shigella spp. | [B]  | [B] Susceptibility of Salmonella spp. to ciprofloxacin can be inferred from pefloxacin disk diffusion susceptibility. | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[D] A disk diffusion test is not yet developed. Perform an MIC test.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [3] For other Enterobacterales, the activity of tigecycline varies from insufficient in Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see http://www.eucast.org/guidance_documents/.
[A] For other Enterobacterales, the activity of tigecycline varies from insufficient in Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see http://www.eucast.org/guidance_documents/. | [B] Zone diameter breakpoints validated for E. coli only. For C. koseri, use an MIC method.
[1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[2] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[C] Zone diameter breakpoints apply to E. coli only. For other Enterobacterales, use an MIC method. | [D] Ignore isolated colonies within the inhibition zone (see pictures below).
[2] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[D] Ignore isolated colonies within the inhibition zone (see pictures below).
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see http://www.eucast.org/guidance_documents/.
[2] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [3] See table of dosages for dosing for different indications.
[3] See table of dosages for dosing for different indications.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see http://www.eucast.org/guidance_documents/.
[A] Zone diameters of ≥20 mm for the cefiderocol 30 µg disk correspond to MIC values below the PK-PD breakpoint of S ≤ 2 mg/L.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see http://www.eucast.org/guidance_documents/.
[A] Zone diameters of ≥17 mm for the cefiderocol 30 µg disk correspond to MIC values below the PK-PD breakpoint of S ≤ 2 mg/L.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L. | [2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2/A] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [B] For S. aureus, disk diffusion is more reliable than MIC determination for detection of penicillinase producers, provided the zone diameter is measured AND the zone edge closely inspected (see pictures below). Examine the zone edge with transmitted light (plate held up to light). If the zone diameter is <26 mm, then report resistant. If the zone diameter is ≥26 mm AND the zone edge is sharp, then report resistant. If not sharp, then report susceptible and if uncertain, then report resistant. Chromogenic cephalosporin-based beta-lactamase tests do not reliably detect staphylococcal penicillinase.
[2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
4.S. aureus,S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[E] For screening for methicillin resistance in S. pseudintermedius and S. schleiferi.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureusare penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most coagulase-negative staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in coagulase-negative staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[4] For staphylococci other than S. aureus, S. lugdunensis and S. saprophyticus, the cefoxitin MIC is a poorer predictor of methicillin resistance than the disk diffusion test.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [B] If coagulase-negative staphylococci are not identified to species level, use zone diameter breakpoints S≥25, R<25 mm.
[4] For staphylococci other than S. aureus, S. lugdunensis and S. saprophyticus, the cefoxitin MIC is a poorer predictor of methicillin resistance than the disk diffusion test.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [B] If coagulase-negative staphylococci are not identified to species level, use zone diameter breakpoints S≥25, R<25 mm.
[5] In S. pseudintermedius and S. schleiferi the cefoxitin disk is less predictive for the detection of methicillin resistance than in other staphylococci. Use the oxacillin 1 µg disk with zone diameter breakpoints S≥20, R<20 mm.
[C] In S. pseudintermedius and S. schleiferi the cefoxitin disk is less predictive for the detection of methicillin resistance than in other staphylococci. Use the oxacillin 1 µg disk with zone diameter breakpoints S≥20, R<20 mm.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[6] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[D] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[6] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[D] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[8] Methicillin-susceptible isolates can be reported susceptible to ceftobiprole without further testing.
[F] Methicillin-susceptible isolates can be reported susceptible to ceftobiprole without further testing.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B] A disk diffusion test is not yet developed. Perform an MIC test.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C]  | [C] Isolates categorised as susceptible to norfloxacin can be reported susceptible to moxifloxacin and "susceptible increased exposure" (I) to ciprofloxacin, levofloxacin and ofloxacin. Isolates categorised as non-susceptible should be tested for susceptibility to individual agents.
[2] Ofloxacin breakpoints for Staphylococcus spp. have been removed since in systemic infections with staphylococci the agent is inferior to other fluoroquinolones. For topical use of ofloxacin, see tables of topical agents.
[D] Ofloxacin breakpoints for Staphylococcus spp. have been removed since in systemic infections with staphylococci the agent is inferior to other fluoroquinolones. For topical use of ofloxacin, see tables of topical agents.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[1] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[A] For systemic infections, aminoglycosides must be used in combination with other active therapy. In this circumstance, the breakpoint/ECOFF in brackets can be used to distinguish between organisms with and without acquired resistance mechanisms. For isolates without resistance mechanisms, include a comment in the report: “Aminoglycosides are often given in combination with other agents, either to support the activity of the aminoglycoside or to broaden the spectrum of therapy. In systemic infections, the aminoglycoside must be supported by other active therapy." For more information, see http://www.eucast.org/guidance_documents/.
[3] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [4] S. aureus isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[3] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [4] S. aureus isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance.
[3] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [5] MRSA isolates susceptible to vancomycin can be reported susceptible to telavancin. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy".
[B] Place the erythromycin and clindamycin disks 12-20 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy".
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[B] For MRSA that test susceptible with disk diffusion, the results should be confirmed with an MIC test.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[3] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Isolates susceptible to linezolid can be reported susceptible to tedizolid.
[A] Isolates susceptible to linezolid can be reported susceptible to tedizolid.
[2] Daptomycin MICs must be determined in the presence of Ca (50 mg/L in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturers' instructions for commercial systems. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Use an MIC method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[3] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[A] Use an MIC method.
[4] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[4] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1/A] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] There are no clinical breakpoints for Enterococcus spp. and moxifloxacin, but moxifloxacin has been used for oral step-down treatment of endocarditis caused by Enterococcus spp. The norfloxacin disk diffusion test or the moxifloxacin MIC ECOFF (1 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[B] There are no clinical breakpoints for Enterococcus spp. and moxifloxacin, but moxifloxacin has been used for oral step-down treatment of endocarditis caused by Enterococcus spp. The norfloxacin disk diffusion test or the moxifloxacin MIC ECOFF (1 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[C]  | [C] Susceptibility of ciprofloxacin and levofloxacin can be inferred from the norfloxacin susceptibility. For moxifloxacin, see comment 1/B.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[3] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[B] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Vancomycin susceptible enterococci exhibit sharp zone edges and do not exhibit colonies in the inhibition zone. Examine zone edges with transmitted light (plate held up to light). If the zone edge is fuzzy, colonies grow within the zone  or if you are uncertain, then perform confirmatory testing with PCR or report resistant (see pictures below) even if the zone diameter is ≥ 12 mm. Isolates must not be reported susceptible before 24 h incubation.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] For more information, see http://www.eucast.org/guidance_documents/.
[1] For more information, see http://www.eucast.org/guidance_documents/.
[2] Lefamulin has insufficient activity against E. faecalis. For E. faecium, the ECOFF of 0.5 mg/L can be used to distinguish wild type from non-wild type isolates.
[A] Lefamulin has insufficient activity against E. faecalis. For E. faecium, the ECOFF of 0.5 mg/L can be used to distinguish wild type from non-wild type isolates.
[3] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[B] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[3] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [4] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[B] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [4] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] A disk diffusion test is not yet developed. Perform an MIC test.
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C]  | [C] Isolates categorised as susceptible to norfloxacin can be reported susceptible to moxifloxacin and as "susceptible increased exposure" (I) to levofloxacin. Isolates categorised as non-susceptible should be tested for susceptibility to individual agents.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[3] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Isolates susceptible to linezolid can be reported susceptible to tedizolid. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Isolates susceptible to linezolid can be reported susceptible to tedizolid. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Daptomycin MICs must be determined in the presence of Ca (50 mg/L in the medium for broth dilution methods; agar dilution methods have not been validated).  Follow the manufacturer's instructions for commercial systems. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Use an MIC method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[3] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [2] For breakpoints and dosing in pneumonia, see table of dosages.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [2] For breakpoints and dosing in pneumonia, see table of dosages.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] For isolates with oxacillin inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L, determine the MIC.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis).
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis).
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] For isolates with oxacillin inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L, determine the MIC.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [D] Perform an MIC or infer susceptibility from the ampicillin 2 µg disk diffusion test with ampicillin breakpoints S≥22, R<19 mm.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [D] Perform an MIC or infer susceptibility from the ampicillin 2 µg disk diffusion test with ampicillin breakpoints S≥22, R<19 mm. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis).
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis).
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[E] For interpretation of the oxacillin disk screen, see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] For isolates with oxacillin inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L, determine the MIC.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] For isolates with oxacillin inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L, determine the MIC.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk screen test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] For isolates with oxacillin inhibition zone <20 mm, or benzylpenicillin MIC >0.06 mg/L, determine the MIC for meropenem.
[3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to norfloxacin can be reported susceptible to moxifloxacin and as "susceptible increased exposure" (I) to levofloxacin. Isolates categorised as non-susceptible should be tested for susceptibility to individual agents.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents. | [3] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents. | [3] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents. | [3] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents. | [3] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit. | [A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] A disk diffusion test is not yet developed. Perform an MIC test.
[1] There are no clinical breakpoints for viridans group streptococci and moxifloxacin, but moxifloxacin has been used for oral step-down treatment of endocarditis caused by viridans group streptococci .The moxifloxacin MIC ECOFF (0.5 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[B] There are no clinical breakpoints for viridans group streptococci and moxifloxacin, but moxifloxacin has been used for oral step-down treatment of endocarditis caused by viridans group streptococci .The moxifloxacin MIC ECOFF (0.5 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[A] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[1] There are no clinical breakpoints for viridans group streptococci and rifampicin, but rifampicin has been used for oral step-down treatment of endocarditis caused by viridans group streptococci. The rifampicin MIC ECOFF (0.125 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid rifampicin resistance mechanisms”, but not as susceptible to rifampicin.
[A] There are no clinical breakpoints for viridans group streptococci and rifampicin, but rifampicin has been used for oral step-down treatment of endocarditis caused by viridans group streptococci. The rifampicin MIC ECOFF (0.125 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid rifampicin resistance mechanisms”, but not as susceptible to rifampicin.
[1/A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [4] Susceptibility can be inferred from amoxicillin-clavulanic acid iv.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [D] Susceptibility can be inferred from amoxicillin-clavulanic acid iv.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [E] Susceptibility can be inferred from ampicillin. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [F] Isolates susceptible to ampicillin can be reported "susceptible, increased exposure” (I) to amoxicillin oral. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[6] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[4] The breakpoints also apply to meningitis.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [4] The breakpoints also apply to meningitis.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] See table of dosages for dosing for different indications.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [2] See table of dosages for dosing for different indications.
[4] The breakpoints also apply to meningitis.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [4] The breakpoints also apply to meningitis.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[1] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below.
[1/A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[3] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[3/E] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk screen test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [D] For benzylpenicillin 1 unit disk screen positive isolates (inhibition zone <12 mm), determine the MIC for meropenem.
[3] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[3/E] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to nalidixic acid can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as non-susceptible may have fluoroquinolone resistance and should be tested against the appropriate agent.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2/A] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2/A] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to nalidixic acid can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as non-susceptible may have fluoroquinolone resistance and should be tested against the appropriate agent.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline and minocycline, but some resistant to tetracycline may be susceptible to minocycline and/or doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] For topical use of chloramphenicol, see tables of topical agents.
[A] For topical use of chloramphenicol, see tables of topical agents.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Azithromycin is always used in conjunction with another effective agent. For testing purposes with the aim of detecting acquired resistance mechanisms, the ECOFF is 1 mg/L.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. The meningitis breakpoint can be used to categorise meropenem for other serious infections.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. The meningitis breakpoint can be used to categorise meropenem for other serious infections.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. The meningitis breakpoint can be used to categorise meropenem for other serious infections. | [3] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. The meningitis breakpoint can be used to categorise meropenem for other serious infections.
[1] Non-susceptible isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. The meningitis breakpoint can be used to categorise meropenem for other serious infections.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. The meningitis breakpoint can be used to categorise meropenem for other serious infections. | [3] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] Breakpoints apply only to use in the prophylaxis of meningococcal disease.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[2] For prophylaxis of meningitis only (refer to national guidelines).
[2] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[2] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[2] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[2] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[5] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[2] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections with vancomycin. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[4] Fidaxomicin breakpoints and ECOFF have not been set because the available data show major variation in MIC distribution between studies.
[5] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections with metronidazole. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[1] Susceptibility to ampicillin, amoxicillin, piperacillin and ticarcillin can be inferred from susceptibility to benzylpenicillin.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L. | [2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] For anaerobic bacteria there is clinical evidence of activity in mixed intra-abdominal infections, but no correlation between MIC values, PK-PD data and clinical outcome. Therefore no breakpoints for susceptibility testing are given.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[1] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[B] Isolates categorised as susceptible to nalidixic acid can be reported susceptible to ciprofloxacin and levofloxacin. Isolates categorised as non-susceptible may have fluoroquinolone resistance and should be tested against the appropriate agent.
[A] Susceptibility inferred from tetracycline screen test.
[A] Susceptibility inferred from tetracycline screen test.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Tetracycline can be used to determine susceptibility to doxycycline.
[1] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Non-wild typeisolates were not available when developing the disk diffusion method.
[1] Inducible clindamycin resistance may occur in Corynebacteria. This can be detected by antagonism of clindamycin activity by a macrolide agent. The clinical significance is unknown. There is currently no recommendation for testing.
[1] Inducible clindamycin resistance may occur in Corynebacteria. This can be detected by antagonism of clindamycin activity by a macrolide agent. The clinical significance is unknown. There is currently no recommendation for testing.
[1] Infer susceptibility from ampicillin susceptibility.
[A] Infer susceptibility from ampicillin susceptibility.
[A] Susceptibility can be inferred from norfloxacin susceptibility. See Note
[1] Susceptibility can be inferred from ciprofloxacin susceptibility.
[B] Susceptibility can be inferred from ciprofloxacin or norfloxacin susceptibility. See Note
[C]  | [C] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance.
[A] Non-wild type isolates were not available when developing the disk diffusion method.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[3] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[B] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Isolates susceptible to tetracycline are also susceptible to doxycycline, but some resistant to tetracycline may be susceptible to doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[A] Isolates susceptible to tetracycline are also susceptible to doxycycline, but some resistant to tetracycline may be susceptible to doxycycline. An MIC method should be used to test doxycycline susceptibility of tetracycline resistant isolates if required.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Read the obvious zone edge and disregard haze or growth within the inhibition zone (see pictures below). | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as susceptible to norfloxacin can be reported "susceptible increased exposure" (I) to ciprofloxacin and levofloxacin. Isolates categorised as resistant to norfloxacin can be reported resistant to ciprofloxacin and levofloxacin.
[A] Non-wild type isolates were not available when developing the disk diffusion method.
[1] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Susceptibility inferred from tetracycline disk diffusion screen test.
[A] Susceptibility inferred from tetracycline disk diffusion screen test.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Breakpoints were determined on MICs performed on Middlebrook 7H11/7H10 medium. The comparability of tests performed by other media has not been established. There is ongoing work to review breakpoints using the EUCAST reference method (described above).
[2] MIC data have been generated with MGIT system and not with the EUCAST reference method. Therefore, it has not been possible to set an ECOFF, nor calibrate MGIT MIC values against the reference method. Consequently, EUCAST cannot endorse the tentative breakpoint set by EMA based on the MGIT method. Breakpoints are pending MIC data with the reference method.
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[2] Breakpoints for nasal decontamination S ≤1, R >256 mg/L (S ≥30, R <18 mm for the mupirocin 200 µg disk). Isolates in the I category are associated with short term suppression (useful preoperatively) but, unlike fully susceptible isolates, long term eradication rates are low.
ND = No ECOFF available.
[2] Breakpoints for nasal decontamination S ≤1, R >256 mg/L (S ≥30, R <18 mm for the mupirocin 200 µg disk). Isolates in the I category are associated with short term suppression (useful preoperatively) but, unlike fully susceptible isolates, long term eradication rates are low.
ND = No ECOFF available.
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H.influenzae and M. catarrhalis).
[1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[B] Susceptibility inferred from ampicillin. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] Aminopenicillin breakpoints in Enterobacterales are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only. Breakpoints for other infections are under review.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[C] Ignore isolated colonies within the inhibition zone.
[5] Agar dilution is the reference method for mecillinam MIC determination.
[C] Ignore isolated colonies within the inhibition zone.
[2] Isolates susceptible to cefadroxil and/or cefalexin can be reported "susceptible, increased exposure” (I) to cefazolin.
[A] Isolates susceptible to cefadroxil and/or cefalexin can be reported "susceptible, increased exposure” (I) to cefazolin.
[3] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[4] The cefoxitin ECOFF (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[4] The cefoxitin ECOFF (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[5] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[7] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [6] See table of dosages for dosing for different indications.
[6] See table of dosages for dosing for different indications.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[3] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[A] Tests with a ciprofloxacin 5 µg disk will not reliably detect low-level resistance in Salmonella spp. To screen for ciprofloxacin resistance in Salmonella spp., use the pefloxacin 5 µg disk. See Note | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[2/C] The pefloxacin 5 µg breakpoint used to screen for clinical fluoroquinolone resistance in Salmonella spp., can also be used to detect fluoroquinolone resistance mechanisms in other Enterobacterales such as E. coli, K. pneumoniae and Shigella spp. | [B]  | [B] Susceptibility of Salmonella spp. to ciprofloxacin can be inferred from the pefloxacin disk diffusion screening test. | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to  Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[D] A disk diffusion test is not yet developed. Perform an MIC test.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [3] For other Enterobacterales, the activity of tigecycline varies from insufficient in Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see https://www.eucast.org/eucastguidancedocuments/.
[A] For other Enterobacterales, the activity of tigecycline varies from insufficient in Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see https://www.eucast.org/eucastguidancedocuments/. | [B] Zone diameter breakpoints validated for E. coli only. For C. koseri, use an MIC method.
[1] The clinical efficacy of chloramphenicol in meningitis has been questioned and breakpoints are currently under review. For chloramphenicol treatment in meningitis, see table of dosages.
[1] The clinical efficacy of chloramphenicol in meningitis has been questioned and breakpoints are currently under review. For chloramphenicol treatment in meningitis, see table of dosages.
[3] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [2] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[4] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[C] Zone diameter breakpoints apply to E. coli only. For other Enterobacterales, use an MIC method. | [D] Ignore isolated colonies within the inhibition zone (see pictures below).
[4] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[D] Ignore isolated colonies within the inhibition zone (see pictures below).
[5] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[5] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[2] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [3] See table of dosages for dosing for different indications.
[3] See table of dosages for dosing for different indications.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[2] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[A] Zone diameters of ≥20 mm for the cefiderocol 30 µg disk correspond to MIC values below the PK-PD breakpoint of S ≤ 2 mg/L.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[A] Zone diameters of ≥17 mm for the cefiderocol 30 µg disk correspond to MIC values below the PK-PD breakpoint of S ≤ 2 mg/L.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L. | [2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2/A] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[2] For information on how to use breakpoints in brackets, see hhttps://www.eucast.org/eucastguidancedocuments/. | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [B] For S. aureus, disk diffusion is more reliable than MIC determination for detection of penicillinase producers, provided the zone diameter is measured AND the zone edge closely inspected (see pictures below). Examine the zone edge with transmitted light (plate held up to light). If the zone diameter is <26 mm, then report resistant. If the zone diameter is ≥26 mm AND the zone edge is sharp (no reduction of growth towards zone edge, like a "cliff"), then report resistant. If not sharp (reduction of growth towards zone edge,  like a "beach"), then report susceptible and if uncertain, then report resistant. Chromogenic cephalosporin-based beta-lactamase tests do not reliably detect staphylococcal penicillinase.
[2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[E] For screening for methicillin resistance in S. pseudintermedius, S. schleiferi and S. coagulans.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [4] S. aureus, S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [4] S. aureus, S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most  staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[4] For staphylococci other than S. aureus, S. lugdunensis and S. saprophyticus, the cefoxitin MIC is a poorer predictor of methicillin resistance than the disk diffusion test.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [B] If coagulase-negative staphylococci are not identified to species level, use zone diameter breakpoints S≥25, R<25 mm.
[4] For staphylococci other than S. aureus, S. lugdunensis and S. saprophyticus, the cefoxitin MIC is a poorer predictor of methicillin resistance than the disk diffusion test.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [B] If coagulase-negative staphylococci are not identified to species level, use zone diameter breakpoints S≥25, R<25 mm.
[5] In S. pseudintermedius,S. schleiferiand S. coagulans the cefoxitin disk is less predictive for the detection of methicillin resistance than in other staphylococci. Use the oxacillin 1 µg disk with zone diameter breakpoints S≥20, R<20 mm.
[C] In S. pseudintermedius,S. schleiferiand S. coagulans the cefoxitin disk is less predictive for the detection of methicillin resistance than in other staphylococci. Use the oxacillin 1 µg disk with zone diameter breakpoints S≥20, R<20 mm.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[6] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[D] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[6] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[D] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[8] Methicillin-susceptible isolates can be reported susceptible to ceftobiprole without further testing.
[F] Methicillin-susceptible isolates can be reported susceptible to ceftobiprole without further testing.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B] A disk diffusion test is not yet developed. Perform an MIC test.
[B] A disk diffusion test is not yet developed. Perform an MIC test.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C]  | [C] Isolates categorised as screen negative can be reported susceptible to moxifloxacin and "susceptible increased exposure" (I) to ciprofloxacin and levofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[2] Ofloxacin breakpoints for Staphylococcus spp. have been removed since in systemic infections with staphylococci the agent is inferior to other fluoroquinolones. For topical use of ofloxacin, see tables of topical agents.
[D] Ofloxacin breakpoints for Staphylococcus spp. have been removed since in systemic infections with staphylococci the agent is inferior to other fluoroquinolones. For topical use of ofloxacin, see tables of topical agents.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[3] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [4] S. aureus isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance.
[3] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [4] S. aureus isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance.
[3] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [5] MRSA isolates susceptible to vancomycin can be reported susceptible to telavancin.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance.
[A] Disk diffusion is unreliable and cannot distinguish between wild type isolates and those with non-vanA-mediated glycopeptide resistance.
[1] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as screen negative can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as screen negative can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as screen negative can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as screen negative can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as screen negative can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as screen negative can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as screen negative can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as screen negative can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy".
[B] Place the erythromycin and clindamycin disks 12-20 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy".
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[B] For MRSA that test susceptible with disk diffusion, the results should be confirmed with an MIC test.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[3] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Isolates susceptible to linezolid can be reported susceptible to tedizolid.
[A] Isolates susceptible to linezolid can be reported susceptible to tedizolid.
[1] The clinical efficacy of chloramphenicol in meningitis has been questioned and breakpoints are currently under review. For chloramphenicol treatment in meningitis, see table of dosages.
[1] The clinical efficacy of chloramphenicol in meningitis has been questioned and breakpoints are currently under review. For chloramphenicol treatment in meningitis, see table of dosages.
[3] Daptomycin MICs must be determined in the presence of Ca (50 mg/L in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturers' instructions for commercial systems. | [2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Use an MIC method. | [2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[4] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[A] Use an MIC method.
[5] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[5] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[2] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[A] Susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) can be inferred from ampicillin. Ampicillin resistance is uncommon in E. faecalis (confirm with MIC) but common in E. faecium.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1/A] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] There are no clinical breakpoints for Enterococcus spp. and moxifloxacin, but moxifloxacin has been used for oral step-down treatment of endocarditis caused by Enterococcus spp. The norfloxacin disk diffusion test or the moxifloxacin MIC ECOFF (1 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[B] There are no clinical breakpoints for Enterococcus spp. and moxifloxacin, but moxifloxacin has been used for oral step-down treatment of endocarditis caused by Enterococcus spp. The norfloxacin disk diffusion test or the moxifloxacin MIC ECOFF (1 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[C]  | [C] Susceptibility to ciprofloxacin and levofloxacin can be inferred from the norfloxacin disk diffusion screening test. For moxifloxacin, see comment 1/B.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[3] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[B] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Vancomycin susceptible enterococci exhibit sharp zone edges and do not exhibit colonies in the inhibition zone. Examine zone edges with transmitted light (plate held up to light). If the zone edge is fuzzy, colonies grow within the zone  or if you are uncertain, then perform confirmatory testing with PCR or report resistant (see pictures below) even if the zone diameter is ≥ 12 mm. Isolates must not be reported susceptible before 24 h incubation.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] For more information, see https://www.eucast.org/eucastguidancedocuments/.
[1] For more information, see https://www.eucast.org/eucastguidancedocuments/.
[2] Lefamulin has insufficient activity against E. faecalis. For E. faecium, the ECOFF of 0.5 mg/L can be used to distinguish wild type from non-wild type isolates.
[A] Lefamulin has insufficient activity against E. faecalis. For E. faecium, the ECOFF of 0.5 mg/L can be used to distinguish wild type from non-wild type isolates.
[3] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[B] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[3] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [4] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[B] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [4] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B.
2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] A disk diffusion test is not yet developed. Perform an MIC test.
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C]  | [C] Isolates categorised as screen negative can be reported susceptible to moxifloxacin and as "susceptible increased exposure" (I) to levofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[3] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Isolates susceptible to linezolid can be reported susceptible to tedizolid. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Isolates susceptible to linezolid can be reported susceptible to tedizolid. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The clinical efficacy of chloramphenicol in meningitis has been questioned and breakpoints are currently under review. For chloramphenicol treatment in meningitis, see table of dosages.
[1] The clinical efficacy of chloramphenicol in meningitis has been questioned and breakpoints are currently under review. For chloramphenicol treatment in meningitis, see table of dosages.
[3] Daptomycin MICs must be determined in the presence of Ca (50 mg/L in the medium for broth dilution methods; agar dilution methods have not been validated).  Follow the manufacturer's instructions for commercial systems. | [2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Use an MIC method. | [2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[4] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[4] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] For breakpoints and dosing in pneumonia, see table of dosages.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [2] For breakpoints and dosing in pneumonia, see table of dosages.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] For isolates with an oxacillin 1 µg zone <9 mm, determine the MIC. For isolates with an oxacillin zone ≥9 mm, report susceptible without further testing.
.
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis).
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis).
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] For isolates with an oxacillin 1 µg zone <9 mm, determine the MIC. For isolates with an oxacillin zone ≥9 mm, report susceptible without further testing.
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[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis).
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis).
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis).
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[D] For interpretation of the oxacillin disk screen, see flow chart below. | [1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] For isolates with an oxacillin 1 µg zone <9 mm, determine the MIC. For isolates with an oxacillin zone ≥9 mm, report susceptible without further testing.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] For isolates with an oxacillin 1 µg zone <9 mm, determine the MIC. For isolates with an oxacillin zone ≥9 mm, report susceptible without further testing.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin inhibition zone ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [C] For isolates with an oxacillin 1 µg zone <9 mm, determine the MIC. For isolates with an oxacillin zone ≥9 mm, report susceptible without further testing.
[3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as screen negative can be reported susceptible to moxifloxacin and as "susceptible increased exposure" (I) to levofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as screen negative can be reported susceptible to doxycycline and minocycline. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] The clinical efficacy of chloramphenicol in meningitis has been questioned and breakpoints are currently under review.For chloramphenicol treatment in meningitis, see table of dosages.
[1] The clinical efficacy of chloramphenicol in meningitis has been questioned and breakpoints are currently under review.For chloramphenicol treatment in meningitis, see table of dosages.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [3] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [3] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [3] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [3] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates (inhibition zone ≥18 mm or MIC ≤0.25 mg/L), susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates (inhibition zone <18 mm or MIC >0.25 mg/L), susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit. | [A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] A disk diffusion test is not yet developed. Perform an MIC test.
[1] There are no clinical breakpoints for viridans group streptococci and moxifloxacin, but moxifloxacin has been used for oral step-down treatment of endocarditis caused by viridans group streptococci. The moxifloxacin MIC ECOFF (0.5 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[B] There are no clinical breakpoints for viridans group streptococci and moxifloxacin, but moxifloxacin has been used for oral step-down treatment of endocarditis caused by viridans group streptococci. The moxifloxacin MIC ECOFF (0.5 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[A] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[1] There are no clinical breakpoints for viridans group streptococci and rifampicin, but rifampicin has been used for oral step-down treatment of endocarditis caused by viridans group streptococci. The rifampicin MIC ECOFF (0.125 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid rifampicin resistance mechanisms”, but not as susceptible to rifampicin.
[A] There are no clinical breakpoints for viridans group streptococci and rifampicin, but rifampicin has been used for oral step-down treatment of endocarditis caused by viridans group streptococci. The rifampicin MIC ECOFF (0.125 mg/L) can be used to screen for resistance mechanisms. When screen negative, the isolate should be reported “wild type” or “devoid rifampicin resistance mechanisms”, but not as susceptible to rifampicin.
[1/A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [4] Susceptibility can be inferred from amoxicillin-clavulanic acid iv.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [D] Susceptibility can be inferred from amoxicillin-clavulanic acid iv.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [E] Susceptibility can be inferred from ampicillin. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [F] Isolates susceptible to ampicillin can be reported "susceptible, increased exposure” (I) to amoxicillin oral.Isolates resistant to ampicillin can be reported resistant to amoxicillin oral. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[6] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [D] For benzylpenicillin 1 unit disk screen positive isolates (inhibition zone <12 mm), determine the MIC.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] See table of dosages for dosing for different indications.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [2] See table of dosages for dosing for different indications.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [D] For benzylpenicillin 1 unit disk screen positive isolates (inhibition zone <12 mm), determine the MIC.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[3] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[3/E] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (inhibition zone ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (inhibition zone <12 mm), see flow chart below. | [D] For benzylpenicillin 1 unit disk screen positive isolates (inhibition zone <12 mm), determine the MIC for meropenem.
[3] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[3/E] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as screen negative can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2/A] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2/A] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as screen negative can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin, clarithromycin and roxithromycin.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] For topical use of chloramphenicol, see tables of topical agents.
[A] For topical use of chloramphenicol, see tables of topical agents.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Azithromycin is always used in conjunction with another effective agent. For testing purposes with the aim of detecting acquired resistance mechanisms, the ECOFF is 1 mg/L.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. 3.The addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. 3.The addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. 3.The addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. 3.The addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. 3.The addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[2] The meropenem zone diameter breakpoint will detect all cfiA gene mediated carbapenem resistance in Bacteroides fragilis. Some isolates with an MIC of 1 mg/L may harbour the cfiA gene.
[A] The meropenem zone diameter breakpoint will detect all cfiA gene mediated carbapenem resistance in Bacteroides fragilis. Some isolates with an MIC of 1 mg/L may harbour the cfiA gene.
[3] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[B] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [C] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] For susceptibility testing purposes, the concentration of  tazobactam is fixed at 4 mg/L.
[A] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] For susceptibility testing purposes, the concentration of  tazobactam is fixed at 4 mg/L.
[A] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] For susceptibility testing purposes, the concentration of  tazobactam is fixed at 4 mg/L.
[A] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] For susceptibility testing purposes, the concentration of  tazobactam is fixed at 4 mg/L.
[A] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[2] Fidaxomicin breakpoints and ECOFF have not been set because the available data show major variation in MIC distributions between studies.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[1] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[B] Isolates categorised as screen negative can be reported susceptible to ciprofloxacin and levofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Susceptibility to doxycycline can be inferred from the tetracycline disk diffusion screening test.
[A] Susceptibility to doxycycline can be inferred from the tetracycline disk diffusion screening test.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[A] Erythromycin can be used to determine susceptibility to azithromycin and clarithromycin.
[1] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Tetracycline can be used to determine susceptibility to doxycycline.
[1] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Tetracycline can be used to determine susceptibility to doxycycline.
[A] Non-wild typeisolates were not available when developing the disk diffusion method.
[1] Inducible clindamycin resistance may occur in Corynebacteria. This can be detected by antagonism of clindamycin activity by a macrolide agent. The clinical significance is unknown. There is currently no recommendation for testing.
[1] Inducible clindamycin resistance may occur in Corynebacteria. This can be detected by antagonism of clindamycin activity by a macrolide agent. The clinical significance is unknown. There is currently no recommendation for testing.
[1] Infer susceptibility from ampicillin susceptibility.
[A] Infer susceptibility from ampicillin susceptibility.
[A] Susceptibility can be inferred from the norfloxacin disk diffusion screening test. See Note
[1] Susceptibility can be inferred from ciprofloxacin susceptibility.
[B] Susceptibility can be inferred from the ciprofloxacin susceptibility or the norfloxacin disk diffusion screening test. See Note
[C]  | [C] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance.
[A] Non-wild type isolates were not available when developing the disk diffusion method.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[3] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[B] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline. Isolates categorised as resistant should be tested for susceptibility to doxycycline or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline. Isolates categorised as resistant should be tested for susceptibility to doxycycline or reported resistant.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Read the obvious zone edge and disregard haze or growth within the inhibition zone (see pictures below). | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[A] Susceptibility to ciprofloxacin and levofloxacin can be inferred from the pefloxacin disk diffusion screening test.
[A] Susceptibility to ciprofloxacin and levofloxacin can be inferred from the pefloxacin disk diffusion screening test.
[A] Susceptibility to ciprofloxacin and levofloxacin can be inferred from the pefloxacin disk diffusion screening test.
[A] Susceptibility to azithromycin can be inferred from the erythromycin disk diffusion screening test.
[A] Susceptibility to azithromycin can be inferred from the erythromycin disk diffusion screening test.
[A] Susceptibility to doxycycline can be inferred from the tetracycline disk diffusion screening test.
[A] Susceptibility to doxycycline can be inferred from the tetracycline disk diffusion screening test.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as screen negative can be reported "susceptible increased exposure" (I) to ciprofloxacin and levofloxacin. Isolates categorised as screen positive can be reported resistant to ciprofloxacin and levofloxacin.
[A] Non-wild type isolates were not available when developing the disk diffusion method.
[1] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Isolates categorised as screen negative can be reported "susceptible increased exposure" (I) to doxycyline. Isolates categorised as screen positive can be reported resistant to doxycycline.
[A] Isolates categorised as screen negative can be reported "susceptible increased exposure" (I) to doxycyline. Isolates categorised as screen positive can be reported resistant to doxycycline.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Breakpoints were determined on MICs performed on Middlebrook 7H11/7H10 medium. The comparability of tests performed by other media has not been established. There is ongoing work to review breakpoints using the EUCAST reference method (described above).
[2] MIC data have been generated with MGIT system and not with the EUCAST reference method. Therefore, it has not been possible to set an ECOFF, nor calibrate MGIT MIC values against the reference method. Consequently, EUCAST cannot endorse the tentative breakpoint set by EMA based on the MGIT method. Breakpoints are pending MIC data with the reference method.
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[2] Breakpoints for nasal decontamination S ≤1, R >256 mg/L (S ≥30, R <18 mm for the mupirocin 200 µg disk). Isolates in the I category are associated with short term suppression (useful preoperatively) but, unlike fully susceptible isolates, long term eradication rates are low.
ND = No ECOFF available.
[2] Breakpoints for nasal decontamination S ≤1, R >256 mg/L (S ≥30, R <18 mm for the mupirocin 200 µg disk). Isolates in the I category are associated with short term suppression (useful preoperatively) but, unlike fully susceptible isolates, long term eradication rates are low.
ND = No ECOFF available.
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for gram positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] The entire C. auris wild-type population is in the I category. The Susceptible category (≤0.001 mg/L) is simply to avoid missclassification of any WT strains as "S" strains.
[2] Isolates that are susceptible to anidulafungin as well as micafungin should be considered susceptible to caspofungin, until caspofungin breakpoints have  been established. EUCAST breakpoints have not yet been established for caspofungin, due to significant inter-laboratory variation in MIC ranges for caspofungin.
[2] Isolates that are susceptible to anidulafungin as well as micafungin should be considered susceptible to caspofungin, until caspofungin breakpoints have  been established. EUCAST breakpoints have not yet been established for caspofungin, due to significant inter-laboratory variation in MIC ranges for caspofungin.
[2] Isolates that are susceptible to anidulafungin as well as micafungin should be considered susceptible to caspofungin, until caspofungin breakpoints have  been established. EUCAST breakpoints have not yet been established for caspofungin, due to significant inter-laboratory variation in MIC ranges for caspofungin.
[2] Isolates that are susceptible to anidulafungin as well as micafungin should be considered susceptible to caspofungin, until caspofungin breakpoints have  been established. EUCAST breakpoints have not yet been established for caspofungin, due to significant inter-laboratory variation in MIC ranges for caspofungin.
[2] Isolates that are susceptible to anidulafungin as well as micafungin should be considered susceptible to caspofungin, until caspofungin breakpoints have  been established. EUCAST breakpoints have not yet been established for caspofungin, due to significant inter-laboratory variation in MIC ranges for caspofungin.
[3] The fluconazole susceptibility of the earliest C. auris strains (likely representing the wild-type, e.g.CBS10913) was low (4 mg/L, determined in-house by EUCAST), and C. auris isolates with low azole MICs are still reported, particularly from South America. However, most C. auris isolates exhibit fluconazole MIC values >16 mg/L and harbour acquired resistance mechanisms. Due to the paucity of true wild-type, non-outbreak isolates, a fluconazole ECOFF cannot be established. Clinical data on isolates with lower MICs (≤ 16 mg/L) are very limited. Therefore, EUCAST has insufficient data to support fluconazole therapy for C. auris, even when the MIC is low.
[4] The entire C. glabrata wild-type population is in the I category. MICs against C. glabrata should be interpreted as resistant when above 16 mg/L. Susceptible category (≤0.001 mg/L) is simply to avoid missclassification of any wild-typestrains as "S" strains.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[6] MICs for C. krusei are approximately three two-fold dilution steps higher than those for C. albicans  and, similarly, those for C. guilliermondii are approximately eight two-fold dilutions higher. In addition, there were only a small number of cases involving these species in the clinical trials. This means there is insufficient evidence (IE) to indicate whether the wild-type population of these pathogens can be considered susceptible to micafungin.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[7] Breakpoints apply for MICs determined with Tween 20 supplemented medium according to the EUCAST E.Def 7.4 method.
[7] Breakpoints apply for MICs determined with Tween 20 supplemented medium according to the EUCAST E.Def 7.4 method.
[7] Breakpoints apply for MICs determined with Tween 20 supplemented medium according to the EUCAST E.Def 7.4 method.
[7] Breakpoints apply for MICs determined with Tween 20 supplemented medium according to the EUCAST E.Def 7.4 method.
[7] Breakpoints apply for MICs determined with Tween 20 supplemented medium according to the EUCAST E.Def 7.4 method.
[7] Breakpoints apply for MICs determined with Tween 20 supplemented medium according to the EUCAST E.Def 7.4 method.
[7] Breakpoints apply for MICs determined with Tween 20 supplemented medium according to the EUCAST E.Def 7.4 method.
[7] Breakpoints apply for MICs determined with Tween 20 supplemented medium according to the EUCAST E.Def 7.4 method.
[8] Strains with MIC values above the S/I breakpoint are rare or not yet reported. The identification and antifungal susceptibility tests on any such isolate must be repeated and if the result is confirmed the isolate sent to a reference laboratory. Until there is evidence regarding clinical response for confirmed isolates with MIC above the current resistant breakpoint they should be reported resistant. A clinical response of 76% was achieved in infections caused by the species listed below when MICs were lower than or equal to the epidemiological cut-offs. Therefore, wild type populations of C. albicans, C. dubliniensis, C. parapsilosis and C. tropicalis are considered susceptible.
[8] Strains with MIC values above the S/I breakpoint are rare or not yet reported. The identification and antifungal susceptibility tests on any such isolate must be repeated and if the result is confirmed the isolate sent to a reference laboratory. Until there is evidence regarding clinical response for confirmed isolates with MIC above the current resistant breakpoint they should be reported resistant. A clinical response of 76% was achieved in infections caused by the species listed below when MICs were lower than or equal to the epidemiological cut-offs. Therefore, wild type populations of C. albicans, C. dubliniensis, C. parapsilosis and C. tropicalis are considered susceptible.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[5] The ECOFFs for these species are in general higher than for C. albicans.
[8] Strains with MIC values above the S/I breakpoint are rare or not yet reported. The identification and antifungal susceptibility tests on any such isolate must be repeated and if the result is confirmed the isolate sent to a reference laboratory. Until there is evidence regarding clinical response for confirmed isolates with MIC above the current resistant breakpoint they should be reported resistant. A clinical response of 76% was achieved in infections caused by the species listed below when MICs were lower than or equal to the epidemiological cut-offs. Therefore, wild type populations of C. albicans, C. dubliniensis, C. parapsilosis and C. tropicalis are considered susceptible.
[2] The ECOFFs for these species are in general one two-fold dilution higher than for A. fumigatus.
[3] For isolates with confirmed MIC 2 mg/L (one dilution above the breakpoint), itraconazole may be considered for treatment of chronic pulmonary aspergillosis when no alternative is available and when  sufficient exposure (>2 mg/L) is ensured via TDM.
[3] For isolates with confirmed MIC 2 mg/L (one dilution above the breakpoint), itraconazole may be considered for treatment of chronic pulmonary aspergillosis when no alternative is available and when  sufficient exposure (>2 mg/L) is ensured via TDM.
[3] For isolates with confirmed MIC 2 mg/L (one dilution above the breakpoint), itraconazole may be considered for treatment of chronic pulmonary aspergillosis when no alternative is available and when  sufficient exposure (>2 mg/L) is ensured via TDM.
[2] The ECOFFs for these species are in general one two-fold dilution higher than for A. fumigatus. | [4] The MIC values for isolates of A. niger and A. versicolor are in general higher than those for A. fumigatus. Whether this translates into a poorer clinical response is unknown.
[3] For isolates with confirmed MIC 2 mg/L (one dilution above the breakpoint), itraconazole may be considered for treatment of chronic pulmonary aspergillosis when no alternative is available and when  sufficient exposure (>2 mg/L) is ensured via TDM.
[2] The ECOFFs for these species are in general one two-fold dilution higher than for A. fumigatus.
[2] The ECOFFs for these species are in general one two-fold dilution higher than for A. fumigatus.
[2] The ECOFFs for these species are in general one two-fold dilution higher than for A. fumigatus.
[2] The ECOFFs for these species are in general one two-fold dilution higher than for A. fumigatus.
[6] For isolates with confirmed MIC 2 mg/L (one dilution above the breakpoint), voriconazole may be considered for treatment of chronic pulmonary aspergillosis when no alternative is available and when sufficient exposure (>2-3 mg/L) is ensured via TDM.
[6] For isolates with confirmed MIC 2 mg/L (one dilution above the breakpoint), voriconazole may be considered for treatment of chronic pulmonary aspergillosis when no alternative is available and when sufficient exposure (>2-3 mg/L) is ensured via TDM.
[2] The ECOFFs for these species are in general one two-fold dilution higher than for A. fumigatus.
[2] The ECOFFs for these species are in general one two-fold dilution higher than for A. fumigatus.
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[B] Susceptibility inferred from ampicillin (iv or oral). | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[C] Isolates susceptible to ampicillin (iv or oral) can be reported "susceptible, increased exposure” (I) to "amoxicillin oral (infections originating from the urinary tract)". Isolates resistant to ampicillin (iv or oral) can be reported resistant to "amoxicillin oral (infections originating from the urinary tract)". | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[B] Susceptibility inferred from ampicillin (iv or oral). | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[3] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[D] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [E] Infer from ampicillin oral, but the report should explain the meaning of breakpoints in brackets. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[3] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [D] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[5] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[F] Ignore isolated colonies within the inhibition zone.
[6] Agar dilution is the reference method for mecillinam MIC determination.
[F] Ignore isolated colonies within the inhibition zone.
[2] Isolates susceptible to cefadroxil and/or cefalexin can be reported "susceptible, increased exposure” (I) to cefazolin.
[A] Isolates susceptible to cefadroxil and/or cefalexin can be reported "susceptible, increased exposure” (I) to cefazolin.
[3] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[4] The cefoxitin cut-off value (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[4] The cefoxitin cut-off value (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[5] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[7] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [6] See table of dosages for dosing for different indications.
[6] See table of dosages for dosing for different indications.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[3] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[A] Tests with a ciprofloxacin 5 µg disk will not reliably detect low-level resistance in Salmonella spp. Perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test. | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with low-level ciprofloxacin resistance (MIC >0.06 mg/L). The available data relate mainly to Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[2] In meningitis, where low-level ciprofloxacin resistance must be excluded, either perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test.
[2/B] In meningitis, where low-level ciprofloxacin resistance must be excluded, either perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test.
[A] Tests with a ciprofloxacin 5 µg disk will not reliably detect low-level resistance in Salmonella spp. Perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test. | [B] In meningitis, where low-level ciprofloxacin resistance must be excluded, either perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test. | [C] The pefloxacin screening test can also be used to detect fluoroquinolone resistance mechanisms in other Enterobacterales such as E. coli, K. pneumoniae and Shigella spp.
[D] A disk diffusion test awaits action from the responsible pharmaceutical company.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [3] For other Enterobacterales, the activity of tigecycline varies from insufficient inSerratia spp., Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see https://www.eucast.org/eucastguidancedocuments/.
[A] For other Enterobacterales, the activity of tigecycline varies from insufficient inSerratia spp., Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see https://www.eucast.org/eucastguidancedocuments/. | [B] Zone diameter breakpoints validated for E. coli only. For C. koseri, use an MIC method.
[1] Efficacy for this order is uncertain. Screening cut-off values can be used to distinguish wild-type isolates from isolates with acquired resistance (MIC >16 mg/L; zone diameter <17 mm for the chloramphenicol 30 µg disk). For chloramphenicol treatment in meningitis, see table of dosages.
[A] Efficacy for this order is uncertain. Screening cut-off values can be used to distinguish wild-type isolates from isolates with acquired resistance (MIC >16 mg/L; zone diameter <17 mm for the chloramphenicol 30 µg disk). For chloramphenicol treatment in meningitis, see table of dosages.
[3] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[B] Use an MIC method (broth microdilution only). | [2] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[5] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems. | [4] Breakpoints for fosfomycin iv are currently under review.
[D] Zone diameter breakpoints apply to E. coli only. For other Enterobacterales, use an MIC method. | [E] Ignore isolated colonies within the inhibition zone (see pictures below). | [4] Breakpoints for fosfomycin iv are currently under review.
[5] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[E] Ignore isolated colonies within the inhibition zone (see pictures below).
[6] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[6] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[2] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [3] See table of dosages for dosing for different indications.
[3] See table of dosages for dosing for different indications.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[2] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[3] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). The ECOFF is 256 mg/L.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[A] Zone diameters of ≥20 mm for the cefiderocol 30 µg disk correspond to MIC values below the PK-PD breakpoint of S ≤ 2 mg/L.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[A] Zone diameters of ≥17 mm for the cefiderocol 30 µg disk correspond to MIC values below the PK-PD breakpoint of S ≤ 2 mg/L.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L. | [2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2/A] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[2] For information on how to use breakpoints in brackets, see hhttps://www.eucast.org/eucastguidancedocuments/. | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[3] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [B] For S. aureus, disk diffusion is more reliable than MIC determination for detection of penicillinase producers, provided the zone diameter is measured AND the zone edge for isolates with zone diameters ≥26 mm is closely inspected (see pictures below). Examine the zone edge with transmitted light (plate held up to light). If the zone diameter is <26 mm, then report resistant. If the zone diameter is ≥26 mm AND the zone edge is sharp (no reduction of growth towards zone edge, like a "cliff"), then report resistant. If not sharp (reduction of growth towards zone edge,  like a "beach"), then report susceptible and if uncertain, then report resistant. Chromogenic cephalosporin-based beta-lactamase tests do not reliably detect staphylococcal penicillinase.
[2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[E] For screening for methicillin resistance in S. pseudintermedius, S. schleiferi and S. coagulans.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [4] S. aureus, S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [4] S. aureus, S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[4] For staphylococci other than S. aureus, S. lugdunensis and S. saprophyticus, the cefoxitin MIC is a poorer predictor of methicillin resistance than the disk diffusion test.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [B] If coagulase-negative staphylococci are not identified to species level, use zone diameter breakpoints S≥25, R<25 mm, with an ATU of 22-24 mm. For isolates with results inside the ATU: identify species, perform PCR for mecA/mecC or report resistant.
[4] For staphylococci other than S. aureus, S. lugdunensis and S. saprophyticus, the cefoxitin MIC is a poorer predictor of methicillin resistance than the disk diffusion test.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [B] If coagulase-negative staphylococci are not identified to species level, use zone diameter breakpoints S≥25, R<25 mm, with an ATU of 22-24 mm. For isolates with results inside the ATU: identify species, perform PCR for mecA/mecC or report resistant.
[5] In S. pseudintermedius,S. schleiferi and S. coagulans the cefoxitin disk is less predictive for the detection of methicillin resistance than in other staphylococci. Use the oxacillin 1 µg disk with zone diameter breakpoints S≥20, R<20 mm.
[C] In S. pseudintermedius,S. schleiferi and S. coagulans the cefoxitin disk is less predictive for the detection of methicillin resistance than in other staphylococci. Use the oxacillin 1 µg disk with zone diameter breakpoints S≥20, R<20 mm.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[6] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[D] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[6] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[D] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[8] Methicillin-susceptible isolates can be reported susceptible to ceftobiprole without further testing.
[F] Methicillin-susceptible isolates can be reported susceptible to ceftobiprole without further testing.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 5/D and 7/F.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[1] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B] A disk diffusion test awaits action from the responsible pharmaceutical company.
[B] A disk diffusion test awaits action from the responsible pharmaceutical company.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C]  | [C] Isolates categorised as screen negative can be reported susceptible to moxifloxacin and "susceptible increased exposure" (I) to ciprofloxacin and levofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[2] Ofloxacin breakpoints for Staphylococcus spp. have been removed since in systemic infections with staphylococci the agent is inferior to other fluoroquinolones. For topical use of ofloxacin, see tables of topical agents.
[D] Ofloxacin breakpoints for Staphylococcus spp. have been removed since in systemic infections with staphylococci the agent is inferior to other fluoroquinolones. For topical use of ofloxacin, see tables of topical agents.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Resistance to amikacin is most reliably determined by testing with kanamycin (MIC >8 mg/L). The corresponding zone diameter for the kanamycin 30 µg disk is R<18 mm for S. aureus and R<22 mm for coagulase-negative staphylococci.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[3] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturers' instructions for commercial systems. | [4] S. aureus isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin.
[A] Disk diffusion is unreliable and cannot distinguish between wild-type isolates and those with non-vanA-mediated glycopeptide resistance.
[3] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturers' instructions for commercial systems. | [4] S. aureus isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin.
[A] Disk diffusion is unreliable and cannot distinguish between wild-type isolates and those with non-vanA-mediated glycopeptide resistance.
[A] Disk diffusion is unreliable and cannot distinguish between wild-type isolates and those with non-vanA-mediated glycopeptide resistance.
[A] Disk diffusion is unreliable and cannot distinguish between wild-type isolates and those with non-vanA-mediated glycopeptide resistance.
[3] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturers' instructions for commercial systems. | [5] MRSA isolates susceptible to vancomycin can be reported susceptible to telavancin.
[A] Disk diffusion is unreliable and cannot distinguish between wild-type isolates and those with non-vanA-mediated glycopeptide resistance.
[A] Disk diffusion is unreliable and cannot distinguish between wild-type isolates and those with non-vanA-mediated glycopeptide resistance.
[A] Disk diffusion is unreliable and cannot distinguish between wild-type isolates and those with non-vanA-mediated glycopeptide resistance.
[1] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in staphylococci. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy".
[B] Place the erythromycin and clindamycin disks 12-20 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy".
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[B] For MRSA that test susceptible with disk diffusion, the results should be confirmed with an MIC test.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[3] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Isolates susceptible to linezolid can be reported susceptible to tedizolid.
[A] Isolates susceptible to linezolid can be reported susceptible to tedizolid.
[2] Daptomycin MICs must be determined in the presence of Ca (50 mg/L in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturers' instructions for commercial systems. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Use an MIC method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[4] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). | [3] Breakpoints for fosfomycin iv are currently under review.
[A] Use an MIC method. | [3] Breakpoints for fosfomycin iv are currently under review.
[5] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[5] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test. | [3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test. | [4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[A] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test. | [1] Aminopenicillin breakpoints in enterococci are based on intravenous administration. For oral administration the breakpoints are relevant for urinary tract infections only.
[2] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test.
[A] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test.
[2] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test.
[A] In E. faecalis, susceptibility to ampicillin, amoxicillin and piperacillin (with and without beta-lactamase inhibitor) is the expected phenotype, while in E. faecium, resistance is common. Isolates resistant to ampicillin can be reported resistant to ampicillin, amoxicillin and piperacillin (with or without inhibitor). For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1/A] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Moxifloxacin has been used in oral follow-up treatment of endocarditis caused by Enterococcus spp. There are no clinical breakpoints but acquired resistance should be excluded (isolates with MIC >1 mg/L). The norfloxacin disk diffusion screen test can be used to exclude resistance mechanisms. When excluded, the isolate should be reported “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[B] Moxifloxacin has been used in oral follow-up treatment of endocarditis caused by Enterococcus spp. There are no clinical breakpoints but acquired resistance should be excluded (isolates with MIC >1 mg/L). The norfloxacin disk diffusion screen test can be used to exclude resistance mechanisms. When excluded, the isolate should be reported “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[C]  | [C] Susceptibility to ciprofloxacin and levofloxacin can be inferred from the norfloxacin disk diffusion screening test. For moxifloxacin, see comment 1/B.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[3] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[B] Isolates with high-level gentamicin resistance may not be high-level resistant to streptomycin. 
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and low-level intrinsic resistant. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide.
Positive test: Isolates with streptomycin MIC >512 mg/L or a zone diameter <14 mm. The isolate is high-level resistant to streptomycin. There will be no synergy with penicillins or glycopeptides.
[2] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Gentamicin can be used to screen for high-level aminoglycoside resistance (HLAR). 
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin and low-level intrinsic resistant. For other aminoglycosides, this may not be the case. Synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm. The isolate is high-level resistant to gentamicin and other aminoglycosides, except streptomycin which must be tested separately if required (see note 3/B). There will be no synergy with penicillins or glycopeptides.
[A] Vancomycin susceptible enterococci exhibit sharp zone edges and do not exhibit colonies in the inhibition zone. Examine zone edges with transmitted light (plate held up to light). If the zone edge is fuzzy, colonies grow within the zone  or if you are uncertain, then perform confirmatory testing with PCR or report resistant (see pictures below) even if the zone diameter is ≥ 12 mm. Isolates must not be reported susceptible before 24 h incubation.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] For more information, see https://www.eucast.org/eucastguidancedocuments/.
[1] For more information, see https://www.eucast.org/eucastguidancedocuments/.
[2] Lefamulin has insufficient activity against E. faecalis. For E. faecium, the ECOFF of 0.5 mg/L can be used to distinguish wild type from non-wild type isolates.
[A] Lefamulin has insufficient activity against E. faecalis. For E. faecium, the ECOFF of 0.5 mg/L can be used to distinguish wild type from non-wild type isolates.
[3] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[B] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole.
[3] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [4] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[B] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type for both E. faecalis and E. faecium is 1 mg/L, with a corresponding zone diameter ECOFF of 21 mm for trimethoprim and 23 mm for trimethoprim-sulfamethoxazole. | [4] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] The susceptibility of streptococcus groups A, B, C and G to penicillins is inferred from the benzylpenicillin susceptibility (indications other than meningitis) with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, for which therapy with either of these agents is considered inadequate. 2.Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to cephalosporins is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[A] The susceptibility of streptococcus groups A, B, C and G to carbapenems is inferred from the benzylpenicillin susceptibility.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] A disk diffusion test awaits action from the responsible pharmaceutical company.
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C]  | [C] Isolates categorised as screen negative can be reported susceptible to moxifloxacin and as "susceptible increased exposure" (I) to levofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to screen for macrolide resistance in Streptococcus groups A, B, C and
[A] Erythromycin can be used to screen for macrolide resistance in Streptococcus groups A, B, C and
[1] Erythromycin can be used to screen for macrolide resistance in Streptococcus groups A, B, C and
[A] Erythromycin can be used to screen for macrolide resistance in Streptococcus groups A, B, C and
[1] Erythromycin can be used to screen for macrolide resistance in Streptococcus groups A, B, C and
[A] Erythromycin can be used to screen for macrolide resistance in Streptococcus groups A, B, C and
[1] Erythromycin can be used to screen for macrolide resistance in Streptococcus groups A, B, C and
[A] Erythromycin can be used to screen for macrolide resistance in Streptococcus groups A, B, C and
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant and consider adding this comment to the report: "Clindamycin may still be used for short-term therapy of less serious skin and soft tissue infections as constitutive resistance is unlikely to develop during such therapy". The clinical importance of inducible clindamycin resistance in combination treatment of severe S. pyogenes infections is not known.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[3] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Isolates susceptible to linezolid can be reported susceptible to tedizolid. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Isolates susceptible to linezolid can be reported susceptible to tedizolid. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Daptomycin MICs must be determined in the presence of Ca (50 mg/L in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Use an MIC method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[3] Breakpoints for trimethoprim are currently under review.
[3] Breakpoints for trimethoprim are currently under review.
[4] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[4] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] For breakpoints and dosing in pneumonia, see table of dosages.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [2] For breakpoints and dosing in pneumonia, see table of dosages.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis).
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (indications other than meningitis).
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (indications other than meningitis).
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis).
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (indications other than meningitis).
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [4] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below. | [B] Susceptibility inferred from ampicillin (indications other than meningitis). | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[C] For interpretation of the oxacillin disk screen, see flow chart below. | [1] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[A] The oxacillin 1 µg disk diffusion screening test or a benzylpenicillin MIC test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (oxacillin zone diameter ≥20 mm, or benzylpenicillin MIC ≤0.06 mg/L) all beta-lactam agents for which clinical breakpoints are available, including those with “Note” can be reported susceptible without further testing, except for cefaclor, which if reported, should be reported as “susceptible, increased exposure” (I). When the screen is positive (oxacillin zone diameter <20 mm, or benzylpenicillin MIC >0.06 mg/L), see flow chart below.
[3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as screen negative can be reported susceptible to moxifloxacin and as "susceptible increased exposure" (I) to levofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Non-wild typeisolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Erythromycin can be used to screen for macrolide resistance in Streptococcus pneumoniae. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in Streptococcus pneumoniae. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in Streptococcus pneumoniae. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in Streptococcus pneumoniae. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in Streptococcus pneumoniae. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in Streptococcus pneumoniae. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in Streptococcus pneumoniae. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in Streptococcus pneumoniae. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[B] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [2] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Efficacy for this species is uncertain. ECOFFs can be used to distinguish wild-type isolates from isolates with acquired resistance (MIC >8 mg/L; zone diameter <21 mm for the chloramphenicol 30 µg disk). For chloramphenicol treatment in meningitis, see table of dosages.
[1/A] Efficacy for this species is uncertain. ECOFFs can be used to distinguish wild-type isolates from isolates with acquired resistance (MIC >8 mg/L; zone diameter <21 mm for the chloramphenicol 30 µg disk). For chloramphenicol treatment in meningitis, see table of dosages.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [3] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [3] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [3] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin.
[1] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [3] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. Isolates categorised as screen negative can be reported susceptible to beta-lactam agents for which clinical breakpoints are listed (including those with “Note”). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant. | [B] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit. | [A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[A] Benzylpenicillin (MIC or disk diffusion) can be used to screen for beta-lactam resistance in viridans group streptococci. See Note 1/A on penicillins.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2/B] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] A disk diffusion test awaits action from the responsible pharmaceutical company.
[1] Moxifloxacin has been used in oral follow-up treatment of endocarditis caused by viridans group streptococci. There are no clinical breakpoints but acquired resistance (isolates with MIC >0.5 mg/L; zone diameter <21 mm for the moxifloxacin 5 µg disk) should be excluded. When excluded, the isolate should be reported “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[B] Moxifloxacin has been used in oral follow-up treatment of endocarditis caused by viridans group streptococci. There are no clinical breakpoints but acquired resistance (isolates with MIC >0.5 mg/L; zone diameter <21 mm for the moxifloxacin 5 µg disk) should be excluded. When excluded, the isolate should be reported “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] MICs must be determined in the presence of polysorbate-80 (0.002% in the medium for broth dilution methods; agar dilution methods have not been validated). Follow the manufacturer's instructions for commercial systems. | [3] Isolates susceptible to vancomycin can be reported susceptible to dalbavancin and oritavancin. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[A] Disk diffusion criteria have not been defined and an MIC method should be used. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[B] Non-wild type isolates were not available when developing the disk diffusion method. | [1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[A] Place the erythromycin and clindamycin disks 12-16 mm apart (edge to edge) and look for antagonism (the D phenomenon) to detect inducible clindamycin resistance. | [1] Inducible clindamycin resistance can be detected by antagonism of clindamycin activity by a macrolide agent. If not detected, then report as tested according to the clinical breakpoints. If detected, then report as resistant.
[1] Rifampicin has been used in oral follow-up treatment of endocarditis caused by viridans group streptococci. There are no clinical breakpoints but acquired resistance (isolates with MIC >0.25 mg/L; zone diameter <21 mm for the rifampicin 5 µg disk) should be excluded. When excluded, the isolate should be reported “devoid of rifampicin resistance mechanisms”, but not as susceptible to rifampicin.
[A] Rifampicin has been used in oral follow-up treatment of endocarditis caused by viridans group streptococci. There are no clinical breakpoints but acquired resistance (isolates with MIC >0.25 mg/L; zone diameter <21 mm for the rifampicin 5 µg disk) should be excluded. When excluded, the isolate should be reported “devoid of rifampicin resistance mechanisms”, but not as susceptible to rifampicin.
[1/A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[3] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [4] Susceptibility can be inferred from amoxicillin-clavulanic acid iv.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [D] Susceptibility can be inferred from amoxicillin-clavulanic acid iv.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [E] Susceptibility can be inferred from ampicillin. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [F] Isolates susceptible to ampicillin can be reported "susceptible, increased exposure” (I) to amoxicillin oral.Isolates resistant to ampicillin can be reported resistant to amoxicillin oral. | [2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[5] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[2] Beta-lactamase positive isolates can be reported resistant to ampicillin, amoxicillin and piperacillin without inhibitors. Tests based on a chromogenic cephalosporin can be used to detect the beta-lactamase.
[6] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all penicillins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for amoxicillin oral and amoxicillin-clavulanic acid oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[2] See table of dosages for dosing for different indications.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below. | [2] See table of dosages for dosing for different indications.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all cephalosporins for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing, except for cefuroxime oral, which if reported, should be reported “susceptible, increased exposure” (I). When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[3] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[3/E] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (zone diameter <12 mm), see flow chart below. | [B] Read the outer edge of zones where an otherwise clear inhibition zone contains an area of growth around the disk, see pictures below.
[A] The benzylpenicillin 1 unit disk diffusion screening test shall be used to exclude beta-lactam resistance mechanisms. When the screen is negative (zone diameter ≥12 mm) all carbapenems for which clinical breakpoints are available, including those with “Note”, can be reported susceptible without further testing. When the screen is positive (zone diameter <12 mm), see flow chart below.
[3] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[3/E] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B] Susceptibility can be inferred from the nalidixic acid screening test.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C]  | [C] Isolates categorised as screen negative can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[A] Clinical evidence for the efficacy of macrolides in H. influenzae respiratory infections is conflicting due to high spontaneous cure rates. Should there be a need to test any macrolide against this species, the epidemiological cut-offs (ECOFFs) should be used to detect strains with acquired resistance. The ECOFFs for each agent are: azithromycin 4 mg/L, clarithromycin 32 mg/L, erythromycin 16 mg/L and telithromycin 8 mg/L. There are insufficient data available to establish an ECOFF for roxithromycin.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[3] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[A] Susceptibility can be inferred from amoxicillin-clavulanic acid.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2/A] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[2/A] The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as screen negative can be reported susceptible to ciprofloxacin, levofloxacin, moxifloxacin and ofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[1] Erythromycin can be used to screen for macrolide resistance in Moraxella catarrhalis. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in Moraxella catarrhalis. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in Moraxella catarrhalis. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in Moraxella catarrhalis. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in Moraxella catarrhalis. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Erythromycin can be used to screen for macrolide resistance in Moraxella catarrhalis. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[A] Erythromycin can be used to screen for macrolide resistance in Moraxella catarrhalis. Isolates categorised as susceptible can be reported susceptible to azithromycin, clarithromycin and roxithromycin. Isolates categorised as resistant should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible to tetracycline can be reported susceptible to doxycycline and minocycline. Isolates categorised as resistant to tetracycline should be tested for susceptibility to individual agents or reported resistant.
[1] For topical use of chloramphenicol, see table of topical agents.
[A] For topical use of chloramphenicol, see table of topical agents.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Always test for beta-lactamase (tests based on a chromogenic cephalosporin can be used). If beta-lactamase positive, report resistant to ampicillin and amoxicillin. If beta-lactamase negative, determine the MIC of benzylpenicillin. Infer the susceptibility to ampicillin and amoxicillin from the benzylpenicillin MIC (do not report benzylpenicillin susceptibility).
[1] Azithromycin is always used in conjunction with another effective agent. For testing purposes with the aim of detecting acquired resistance mechanisms, the ECOFF is 1 mg/L.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. | [3] The addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] Resistant isolates are rare or not yet reported. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed and the isolate sent to a reference laboratory. | [2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only.
[2] Breakpoints for serious N. meningitidis systemic infections (meningitis with or without septicemia) have been determined for meropenem only. | [3] The addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] Tetracycline can be used to predict susceptibility to minocycline for prophylaxis against N. meningitidis infections.
[1] For chloramphenicol treatment in meningitis, see table of dosages.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] Aminopenicillins without beta-lactamase inhibitors are rarely active against Bacteroides spp. and EUCAST has refrained from setting breakpoints for ampicillin and amoxicillin without inhibitors.
[1] Aminopenicillins without beta-lactamase inhibitors are rarely active against Bacteroides spp. and EUCAST has refrained from setting breakpoints for ampicillin and amoxicillin without inhibitors.
[3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] Aminopenicillins without beta-lactamase inhibitors are rarely active against Bacteroides spp. and EUCAST has refrained from setting breakpoints for ampicillin and amoxicillin without inhibitors.
[1] Aminopenicillins without beta-lactamase inhibitors are rarely active against Bacteroides spp. and EUCAST has refrained from setting breakpoints for ampicillin and amoxicillin without inhibitors.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[5] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[5] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [B] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [2] At very low concentrations of ampicillin, amoxicillin and piperacillin when in inhibitor combinations, the in vitro antimicrobial activity of the fixed concentration of inhibitor (2 mg/L for clavulanic acid and 4 mg/L for sulbactam and tazobactam) is such that artefactually low MIC values may be obtained. Therefore no breakpoints can be given. This does not affect disk diffusion where the concentration of the inhibitor decreases proportionally with the concentration of the agent.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [B] Susceptibility can be inferred from ampicillin.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [2] At very low concentrations of ampicillin, amoxicillin and piperacillin when in inhibitor combinations, the in vitro antimicrobial activity of the fixed concentration of inhibitor (2 mg/L for clavulanic acid and 4 mg/L for sulbactam and tazobactam) is such that artefactually low MIC values may be obtained. Therefore no breakpoints can be given. This does not affect disk diffusion where the concentration of the inhibitor decreases proportionally with the concentration of the agent.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [2] At very low concentrations of ampicillin, amoxicillin and piperacillin when in inhibitor combinations, the in vitro antimicrobial activity of the fixed concentration of inhibitor (2 mg/L for clavulanic acid and 4 mg/L for sulbactam and tazobactam) is such that artefactually low MIC values may be obtained. Therefore no breakpoints can be given. This does not affect disk diffusion where the concentration of the inhibitor decreases proportionally with the concentration of the agent.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[C] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [B] Susceptibility can be inferred from ampicillin.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [4] For susceptibility testing purposes, the concentration of  tazobactam is fixed at 4 mg/L.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[C] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [B] Susceptibility can be inferred from ampicillin.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [4] For susceptibility testing purposes, the concentration of  tazobactam is fixed at 4 mg/L.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[C] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [2] At very low concentrations of ampicillin, amoxicillin and piperacillin when in inhibitor combinations, the in vitro antimicrobial activity of the fixed concentration of inhibitor (2 mg/L for clavulanic acid and 4 mg/L for sulbactam and tazobactam) is such that artefactually low MIC values may be obtained. Therefore no breakpoints can be given. This does not affect disk diffusion where the concentration of the inhibitor decreases proportionally with the concentration of the agent.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [B] Susceptibility can be inferred from ampicillin.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [2] At very low concentrations of ampicillin, amoxicillin and piperacillin when in inhibitor combinations, the in vitro antimicrobial activity of the fixed concentration of inhibitor (2 mg/L for clavulanic acid and 4 mg/L for sulbactam and tazobactam) is such that artefactually low MIC values may be obtained. Therefore no breakpoints can be given. This does not affect disk diffusion where the concentration of the inhibitor decreases proportionally with the concentration of the agent.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [2] At very low concentrations of ampicillin, amoxicillin and piperacillin when in inhibitor combinations, the in vitro antimicrobial activity of the fixed concentration of inhibitor (2 mg/L for clavulanic acid and 4 mg/L for sulbactam and tazobactam) is such that artefactually low MIC values may be obtained. Therefore no breakpoints can be given. This does not affect disk diffusion where the concentration of the inhibitor decreases proportionally with the concentration of the agent.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [C] Susceptibility to ceftriaxone can be inferred from the cefotaxime disk diffusion test.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents. | [C] Susceptibility to ceftriaxone can be inferred from the cefotaxime disk diffusion test.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[1] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[A] Isolates susceptible to benzylpenicillin can be reported susceptible to all beta-lactam agents with breakpoints (including those with Note) without further testing. Isolates resistant to benzylpenicillin should be tested for susceptibility to individual agents.
[D] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[2] Fidaxomicin breakpoints and ECOFF have not been set because the available data show major variation in MIC distributions between studies.
[1] The breakpoints are based on epidemiological cut-off values (ECOFFs) and apply to oral treatment of C. difficile infections. There are no conclusive clinical data regarding the relation between MICs and outcomes.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[1] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[A] The nalidixic acid disk diffusion test can be used to screen for fluoroquinolone resistance. See Note B.
[B] Isolates categorised as screen negative can be reported susceptible to ciprofloxacin and levofloxacin. Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[A] Susceptibility to doxycycline can be inferred from the tetracycline disk diffusion screening test.
[A] Susceptibility to doxycycline can be inferred from the tetracycline disk diffusion screening test.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Susceptibility to azithromycin and clarithromycin can be inferred from erythromycin.
[A] Susceptibility to azithromycin and clarithromycin can be inferred from erythromycin.
[1] Susceptibility to azithromycin and clarithromycin can be inferred from erythromycin.
[A] Susceptibility to azithromycin and clarithromycin can be inferred from erythromycin.
[1] Susceptibility to azithromycin and clarithromycin can be inferred from erythromycin.
[A] Susceptibility to azithromycin and clarithromycin can be inferred from erythromycin.
[1] Susceptibility to azithromycin and clarithromycin can be inferred from erythromycin.
[A] Susceptibility to azithromycin and clarithromycin can be inferred from erythromycin.
[1] Susceptibility to doxycycline can be inferred from tetracycline.
[A] Susceptibility to doxycycline can be inferred from tetracycline.
[1] Susceptibility to doxycycline can be inferred from tetracycline.
[A] Susceptibility to doxycycline can be inferred from tetracycline.
[A] Non-wild typeisolates were not available when developing the disk diffusion method.
[1] Inducible clindamycin resistance may occur in Corynebacterium spp. This can be detected by antagonism of clindamycin activity by a macrolide agent. The clinical significance is unknown. There is currently no recommendation for testing.
[1] Inducible clindamycin resistance may occur in Corynebacterium spp. This can be detected by antagonism of clindamycin activity by a macrolide agent. The clinical significance is unknown. There is currently no recommendation for testing.
[1] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported susceptible to amoxicillin. Isolates resistant to benzylpenicillin should be tested for susceptibility to amoxicillin or reported resistant.
[A] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported susceptible to amoxicillin. Isolates resistant to benzylpenicillin should be tested for susceptibility to amoxicillin or reported resistant.
[1] Susceptibility to cefotaxime can be inferred from benzylpenicillin.
[A] Susceptibility to cefotaxime can be inferred from benzylpenicillin.
[1] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported susceptible to meropenem. Isolates resistant to benzylpenicillin should be tested for susceptibility to meropenem or reported resistant.
[A] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported susceptible to meropenem. Isolates resistant to benzylpenicillin should be tested for susceptibility to meropenem or reported resistant.
[1] Wild-type C. ulcerans is less susceptible to clindamycin.
[1] Wild-type C. ulcerans is less susceptible to clindamycin.
[1] Susceptibility to doxycycline can be inferred from tetracycline.
[A] Susceptibility to doxycycline can be inferred from tetracycline.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Infer susceptibility from ampicillin susceptibility.
[A] Infer susceptibility from ampicillin susceptibility.
[A] Susceptibility can be inferred from the norfloxacin disk diffusion screening test. See Note
[1] Susceptibility can be inferred from ciprofloxacin susceptibility.
[B] Susceptibility can be inferred from the ciprofloxacin susceptibility or the norfloxacin disk diffusion screening test. See Note
[C]  | [C] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance.
[A] Non-wild type isolates were not available when developing the disk diffusion method.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Infer susceptibility from benzylpenicillin susceptibility.
[3] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[B] The intrinsic activity of clavulanic acid in K. kingae is such that the organism is inhibited by 2 mg/L clavulanic acid.Therefore no breakpoints for amoxicillin-clavulanic acid can be given.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Susceptibility can be inferred from erythromycin susceptibility.
[A] Infer susceptibility from erythromycin susceptibility.
[1] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline. Isolates categorised as resistant should be tested for susceptibility to doxycycline or reported resistant.
[A] Tetracycline can be used to screen for resistance in tetracycline agents. Isolates categorised as susceptible can be reported susceptible to doxycycline. Isolates categorised as resistant should be tested for susceptibility to doxycycline or reported resistant.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] Read the obvious zone edge and disregard haze or growth within the inhibition zone (see pictures below). | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[A] Susceptibility to ciprofloxacin and levofloxacin can be inferred from the pefloxacin disk diffusion screening test.
[A] Susceptibility to ciprofloxacin and levofloxacin can be inferred from the pefloxacin disk diffusion screening test.
[A] Susceptibility to ciprofloxacin and levofloxacin can be inferred from the pefloxacin disk diffusion screening test.
[A] Susceptibility to azithromycin (and erythromycin when azithromycin is not available) is inferred from the erythromycin disk diffusion test.
[1/A] Susceptibility to azithromycin (and erythromycin when azithromycin is not available) is inferred from the erythromycin disk diffusion test.
[A] Susceptibility to doxycycline (and tetracycline when doxycycline is not available) is inferred from the tetracycline disk diffusion test.
[1/A] Susceptibility to doxycycline (and tetracycline when doxycycline is not available) is inferred from the tetracycline disk diffusion test.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[A] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[B]  | [B] Isolates categorised as screen negative can be reported "susceptible increased exposure" (I) to ciprofloxacin and levofloxacin. Isolates categorised as screen positive can be reported resistant to ciprofloxacin and levofloxacin.
[A] Non-wild type isolates were not available when developing the disk diffusion method.
[1] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[A] Isolates categorised as screen negative can be reported "susceptible increased exposure" (I) to doxycyline. Isolates categorised as screen positive can be reported resistant to doxycycline.
[A] Isolates categorised as screen negative can be reported "susceptible increased exposure" (I) to doxycyline. Isolates categorised as screen positive can be reported resistant to doxycycline.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Breakpoints were determined on MICs performed on Middlebrook 7H11/7H10 medium. The comparability of tests performed by other media has not been established. There is ongoing work to review breakpoints using the EUCAST reference method (described above).
[2] A provisional screen value of ≤2 mg/L can be used for antimicrobial susceptibility testing with Mycobacteria Growth Indicator Tube (MGIT, Becton Dickinson). There are insufficient MIC data with the reference method to set a clinical breakpoint.
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[2] Breakpoints for nasal decontamination S ≤1, R >256 mg/L (S ≥30, R <18 mm for the mupirocin 200 µg disk). Isolates in the I category are associated with short term suppression (useful preoperatively) but, unlike fully susceptible isolates, long term eradication rates are low.
ND = No ECOFF available.
[2] Breakpoints for nasal decontamination S ≤1, R >256 mg/L (S ≥30, R <18 mm for the mupirocin 200 µg disk). Isolates in the I category are associated with short term suppression (useful preoperatively) but, unlike fully susceptible isolates, long term eradication rates are low.
ND = No ECOFF available.
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] Screening agent for detection of fluoroquinolone resistance (pefloxacin for Enterobacterales, norfloxacin for Gram-positive organisms and nalidixic acid for H. influenzae and M. catarrhalis).
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[2] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[B] Susceptibility inferred from ampicillin (iv or oral). | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[C] Isolates susceptible to ampicillin (iv or oral) can be reported "susceptible, increased exposure” (I) to "amoxicillin oral (infections originating from the urinary tract)". Isolates resistant to ampicillin (iv or oral) can be reported resistant to "amoxicillin oral (infections originating from the urinary tract)". | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[B] Susceptibility inferred from ampicillin (iv or oral). | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[3] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[D] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [E] Infer from ampicillin oral, but the report should explain the meaning of breakpoints in brackets. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[3] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[A] Ignore growth that may appear as a thin inner zone on some batches of Mueller-Hinton agars. | [D] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [1] For information on how to implement the new aminopenicillin breakpoints, see https://www.eucast.org/eucastguidancedocuments/.
[5] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[F] Ignore isolated colonies within the inhibition zone.
[6] Agar dilution is the reference method for mecillinam MIC determination.
[F] Ignore isolated colonies within the inhibition zone.
[2] Isolates susceptible to cefadroxil and/or cefalexin can be reported "susceptible, increased exposure” (I) to cefazolin.
[A] Isolates susceptible to cefadroxil and/or cefalexin can be reported "susceptible, increased exposure” (I) to cefazolin.
[3] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[4] The cefoxitin cut-off value (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[4] The cefoxitin cut-off value (8 mg/L) has a high sensitivity but poor specificity for identification of AmpC-producing Enterobacterales as this agent is also affected by permeability alterations and some carbapenemases. Classical non-AmpC producers are wild type, whereas plasmid AmpC producers or chromosomal AmpC hyperproducers are non-wild type.
[5] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[7] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [6] See table of dosages for dosing for different indications.
[6] See table of dosages for dosing for different indications.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[2] The intrinsically low activity of imipenem against Morganella morganii, Proteus spp. and Providencia spp. requires the high exposure of imipenem.
[3] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] The aztreonam breakpoints for Enterobacterales will detect clinically important resistance mechanisms (including ESBL). Some isolates that produce beta-lactamases are susceptible to aztreonam with these breakpoints and should be reported as tested, i.e. the presence or absence of an ESBL does not in itself influence the categorisation of susceptibility. ESBL detection and characterisation are recommended for public health and infection control purposes.
[1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with any detectable fluoroquinolone resistance mechanisms. The available data relate mainly to Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[A] Tests with a ciprofloxacin 5 µg disk will not reliably exclude all fluoroquinolone resistance mechanisms in Salmonella spp. Perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test. | [1] There is clinical evidence for ciprofloxacin to indicate a poor response in systemic infections caused by Salmonella spp. with any detectable fluoroquinolone resistance mechanisms. The available data relate mainly to Salmonella Typhi but there are also case reports of poor response with other Salmonella species.
[2] In meningitis, where all fluoroquinolone resistance mechanisms must be excluded, either perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test.
[2/B] In meningitis, where all fluoroquinolone resistance mechanisms must be excluded, either perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test.
[A] Tests with a ciprofloxacin 5 µg disk will not reliably exclude all fluoroquinolone resistance mechanisms in Salmonella spp. Perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test. | [B] In meningitis, where all fluoroquinolone resistance mechanisms must be excluded, either perform an MIC test, or infer susceptibility from the pefloxacin 5 µg screening test. | [C] The pefloxacin screening test can also be used to detect fluoroquinolone resistance mechanisms in other Enterobacterales such as E. coli, K. pneumoniae and Shigella spp.
[D] A disk diffusion test awaits action from the responsible pharmaceutical company.
[3] Fluoroquinolone breakpoints are available for other agents.
[3] Fluoroquinolone breakpoints are available for other agents.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[2] For tigecycline broth microdilution MIC determination, the medium must be prepared fresh on the day of use. | [3] For other Enterobacterales, the activity of tigecycline varies from insufficient in Serratia spp., Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see https://www.eucast.org/eucastguidancedocuments/.
[A] For other Enterobacterales, the activity of tigecycline varies from insufficient in Serratia spp., Proteus spp., Morganella morganii and Providencia spp. to variable in other species. For more information, see https://www.eucast.org/eucastguidancedocuments/. | [B] Zone diameter breakpoints validated for E. coli only. For C. koseri, use an MIC method.
[1] Efficacy for Enterobacterales is uncertain. Screening cut-off values can be used to distinguish wild-type isolates from isolates with acquired resistance (MIC >16 mg/L; zone diameter <17 mm for the chloramphenicol 30 µg disk). For chloramphenicol treatment in meningitis, see table of dosages.
[A] Efficacy for Enterobacterales is uncertain. Screening cut-off values can be used to distinguish wild-type isolates from isolates with acquired resistance (MIC >16 mg/L; zone diameter <17 mm for the chloramphenicol 30 µg disk). For chloramphenicol treatment in meningitis, see table of dosages.
[3] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[B] Use an MIC method (broth microdilution only). | [2] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[4] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[D] Ignore isolated colonies within the inhibition zone (see pictures below).
[5] There is currently a lack of clinical evidence to support clinical breakpoints.
[E] There is currently a lack of clinical evidence to support clinical breakpoints.
[6] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy in other Enterobacterales, see https://www.eucast.org/eucastguidancedocuments/.
[F] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy in other Enterobacterales, see https://www.eucast.org/eucastguidancedocuments/.
[4] Agar dilution is the reference method for fosfomycin. MICs must be determined in the presence of glucose-6-phosphate (25 mg/L in the medium). Follow the manufacturers' instructions for commercial systems.
[D] Ignore isolated colonies within the inhibition zone (see pictures below).
[7] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[7] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[2] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [3] See table of dosages for dosing for different indications.
[3] See table of dosages for dosing for different indications.
[1] For susceptibility testing purposes, the concentration of relebactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of vaborbactam is fixed at 8 mg/L.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[2] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[3] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[B] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[A] Zone diameters of ≥20 mm for the cefiderocol 30 µg disk correspond to MIC values below the PK-PD breakpoint of S ≤ 2 mg/L.
[1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[A] There may be growth within the inhibition zone. The density of growth may vary from a fine haze to substantial growth (see pictures below). If any zone edge can be seen, ignore growth within the inhibition zone and read the zone diameter. | [1] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Broth microdilution MIC determination must be performed in iron-depleted Mueller-Hinton broth and specific reading instructions must be followed. For testing conditions and reading instructions, see https://www.eucast.org/eucastguidancedocuments/.
[A] Zone diameters of ≥17 mm for the cefiderocol 30 µg disk correspond to MIC values below the PK-PD breakpoint of S ≤ 2 mg/L.
[1] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1/A] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1/A] The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor. Therefore the addition of the beta-lactamase inhibitor does not add clinical benefit.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[A] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[2] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[A] Use an MIC method (broth microdilution only). | [1] Colistin MIC determination should be performed with broth microdilution. Quality control must be performed with both a susceptible QC strain (E. coli ATCC 25922 or P. aeruginosa ATCC 27853) and the colistin resistant E. coli NCTC 13846 (mcr-1 positive).
[3] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[B] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[4] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[4] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [B] For S. aureus, disk diffusion is more reliable than MIC determination for detection of penicillinase producers, provided the zone diameter is measured AND the zone edge for isolates with zone diameters ≥26 mm is closely inspected (see pictures below). Examine the zone edge with transmitted light (plate held up to light). If the zone diameter is <26 mm, then report resistant. If the zone diameter is ≥26 mm AND the zone edge is sharp (no reduction of growth towards zone edge, like a "cliff"), then report resistant. If not sharp (reduction of growth towards zone edge,  like a "beach"), then report susceptible and if uncertain, then report resistant. Chromogenic cephalosporin-based beta-lactamase tests do not reliably detect staphylococcal penicillinase.
[2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [3] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described. | [D] Ampicillin susceptible S. saprophyticus are mecA-negative and susceptible to ampicillin, amoxicillin and piperacillin (without or with a beta-lactamase inhibitor).
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins.
[C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[E] For screening for methicillin resistance in S. pseudintermedius, S. intermedius, S. schleiferi and S. coagulans.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [4] S. aureus, S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [4] S. aureus, S. lugdunensis and S. saprophyticus with oxacillin MIC values >2 mg/L are mostly methicillin resistant due to the presence of the mecA or mecC gene. Occasionally oxacillin MIC values are high in S. aureus in absence of mec-gene mediated resistance. These isolates have been called BORSA (borderline oxacillin resistant S. aureus). EUCAST does not recommend systematic screening for BORSA. For coagulase-negative staphylococci other than S. saprophyticus and S. lugdunensis, the oxacillin MIC in methicillin resistant isolates is >0.25 mg/L.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [2] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[A] Most S. aureus are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. Isolates that test susceptible to benzylpenicillin and cefoxitin can be reported susceptible to all penicillins. Isolatesthat test resistant to benzylpenicillin but susceptible to cefoxitin are susceptible to β-lactam β-lactamase inhibitor combinations, the isoxazolylpenicillins (oxacillin, cloxacillin, dicloxacillin and flucloxacillin) and nafcillin. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. Isolates that test resistant to cefoxitin are resistant to all penicillins. | [C] Most staphylococci are penicillinase producers and some are methicillin resistant. Either mechanism renders them resistant to benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, piperacillin and ticarcillin. No currently available method can reliably detect penicillinase production in all species of staphylococci but methicillin resistance can be detected with cefoxitin as described.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[4] For staphylococci other than S. aureus, S. lugdunensis and S. saprophyticus, the cefoxitin MIC is a poorer predictor of methicillin resistance than the disk diffusion test.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F. | [B] If coagulase-negative staphylococci are not identified to species level, use zone diameter breakpoints S≥25, R<25 mm, with an ATU of 22-24 mm. For isolates with results inside the ATU: identify species, perform PCR for mecA/mecC or report resistant.
[4] For staphylococci other than S. aureus, S. lugdunensis and S. saprophyticus, the cefoxitin MIC is a poorer predictor of methicillin resistance than the disk diffusion test.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F. | [B] If coagulase-negative staphylococci are not identified to species level, use zone diameter breakpoints S≥25, R<25 mm, with an ATU of 22-24 mm. For isolates with results inside the ATU: identify species, perform PCR for mecA/mecC or report resistant.
[5] In S. pseudintermedius,S. intermedius, S. schleiferi and S. coagulans the cefoxitin disk is less predictive for the detection of methicillin resistance than in other staphylococci. Use the oxacillin 1 µg disk with zone diameter breakpoints S≥20, R<20 mm.
[C] In S. pseudintermedius,S. intermedius, S. schleiferi and S. coagulans the cefoxitin disk is less predictive for the detection of methicillin resistance than in other staphylococci. Use the oxacillin 1 µg disk with zone diameter breakpoints S≥20, R<20 mm.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[6] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[D] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[6] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[D] Methicillin-susceptible isolates can be reported susceptible to ceftaroline without further testing.
[8] Methicillin-susceptible isolates can be reported susceptible to ceftobiprole without further testing.
[F] Methicillin-susceptible isolates can be reported susceptible to ceftobiprole without further testing.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F. | [2] See table of dosages.
3.S. aureus and S. lugdunensis with cefoxitin MIC values >4 mg/L and S. saprophyticus with cefoxitin MIC values >8 mg/L are methicillin resistant, mostly due to the presence of the mecA or mecC gene. Disk diffusion reliably predicts methicillin resistance.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten and ceftolozane-tazobactam, which do not have breakpoints and should not be used for staphylococcal infections. For agents given orally, care to achieve sufficient exposure at the site of the infection should be exercised. If cefotaxime and ceftriaxone are reported for methicillin-susceptible staphylococci, these should be reported “Susceptible, increased exposure” (I). Some methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 6/D and 8/F.