[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 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.
[2] 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] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[2] 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] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C] A disk diffusion test awaits action from the responsible pharmaceutical company.
[C] 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
[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
[D]  | [D] Isolates categorised as screen negative can be reported susceptible to moxifloxacin and "susceptible increased exposure" (I) to levofloxacin. For ciprofloxacin, the isolate is without phenotypically detectable resistance mechanisms and can be used in high exposure in combination therapy (see Note 2/A). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[3] 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.
[E] 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/.
[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/.
[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] Coagulase-negative staphylococci susceptible to both vancomycin and teicoplanin can be reported susceptible to dalbavancin. | [5] 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. | [5] 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. | [6] 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.
[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.
[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 acquired resistance has been 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 acquired resistance has been 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 the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[3] Isolates screening positive with gentamicin for aminoglycoside-modifying enzymes may still exhibit synergy with streptomycin. This can be screened for with streptomycin testing.
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and 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. Combinations between penicillins or glycopeptides and streptomycin will not be synergistic.
[B] Isolates screening positive with gentamicin for aminoglycoside-modifying enzymes may still exhibit synergy with streptomycin. This can be screened for with streptomycin testing.
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and 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. Combinations between penicillins or glycopeptides and streptomycin will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[1] Vancomycin resistance is the expected phenotype for E. casseliflavus and E. gallinarum and therefore susceptibility testing should not be performed.
[A] Vancomycin resistance is the expected phenotype for E. casseliflavus and E. gallinarum and therefore susceptibility testing should not be performed. | [B] 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] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[A] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[3] 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.
[B] 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.
[4] 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.
[C] 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] 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. | [5] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[C] 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. | [5] 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 manufacturers' 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 manufacturers' 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 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.
[3] The activity of trimethoprim is uncertain against S. agalactiae and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type is 2 mg/L.
[B] The activity of trimethoprim is uncertain against S. agalactiae and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type is 2 mg/L.
[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 acquired resistance has been 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 acquired resistance has been excluded, the isolate should be reported “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[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 manufacturers' 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 manufacturers' 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. | [D] For benzylpenicillin screen positive isolates (zone <12 mm), determine the MIC in meningitis.
[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. | [D] For benzylpenicillin screen positive isolates (zone <12 mm), determine the MIC in meningitis.
[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. | [D] For benzylpenicillin screen positive isolates (zone <12 mm), determine the MIC in meningitis.
[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] 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.
[1] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[3] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L.
[4] 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/.
[4] 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.
[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] 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] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported "susceptible, increased exposure” (I) to cefotaxime. Isolates resistant to benzylpenicillin should be tested for susceptibility to cefotaxime or reported resistant.
[A] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported "susceptible, increased exposure” (I) to cefotaxime. Isolates resistant to benzylpenicillin should be tested for susceptibility to cefotaxime or reported resistant.
[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] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[A] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline 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] 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] 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] 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] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[A] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[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/.
[1] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[A] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[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/. | [B] Examine zones carefully for colonies close to the zone edge. Colonies should be taken into account when reading.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[C] Read the obvious zone edges and disregard haze or faint growth within the inhibition zone. | [2] 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] 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 not determined with the EUCAST reference method. Therefore they are provisory values that might change according to the results on ongoing studies using the EUCAST reference protocol for MIC determination.
[1] Breakpoints were not determined with the EUCAST reference method. Therefore they are provisory values that might change according to the results on ongoing studies using the EUCAST reference protocol for MIC determination.
[1] Breakpoints were not determined with the EUCAST reference method. Therefore they are provisory values that might change according to the results on ongoing studies using the EUCAST reference protocol for MIC determination. | [2] A provisional screen value of 2 mg/L is advised according to published MIC data determined with MGIT.
[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 decolonization in carriers of S. aureus, S ≤1, R >1 mg/L (disk diffusion with mupirocin 200 µg disk S ≥30, R <30 mm). For short term suppression of nasal colonization (usually as a perioperative practice) breakpoints of S ≤256, R >256 mg/L (disk diffusion S ≥18 mm, R <18 mm) can be used.
ND = No ECOFF available.
[2] Breakpoints for nasal decolonization in carriers of S. aureus, S ≤1, R >1 mg/L (disk diffusion with mupirocin 200 µg disk S ≥30, R <30 mm). For short term suppression of nasal colonization (usually as a perioperative practice) breakpoints of S ≤256, R >256 mg/L (disk diffusion S ≥18 mm, R <18 mm) can be used.
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] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and "amoxicillin oral (other indications)" can be used in high exposure in combination therapy (see Note 3/D). Isolates resistant to ampicillin can be reported resistant. | [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] For susceptibility testing purposes, the concentration of enmetazobactam is fixed at 8 mg/L.
[4] 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/.
[5] 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] 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.
[6] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[8] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [7] See table of dosages for dosing for different indications.
[7] 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.
[2] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[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/.
[1] Azithromycin has been used in the treatment of enteric infections, primarily with Salmonella Typhi and Shigella species and although wild type distributions vary somewhat, isolates with MICs above 16 mg/L (azithromycin 15 µg disk zone diameters <12 mm) are likely to have azithromycin resistance mechanisms.
[1/A] Azithromycin has been used in the treatment of enteric infections, primarily with Salmonella Typhi and Shigella species and although wild type distributions vary somewhat, isolates with MICs above 16 mg/L (azithromycin 15 µg disk zone diameters <12 mm) are likely to have azithromycin resistance mechanisms. | [B] When reading azithromycin zone diameters, take growth appearing as a thin inner zone on some batches of Mueller-Hinton agar into account.
[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] The addition of a beta-lactamase inhibitor does not add clinical benefit.The beta-lactamases produced by the organisms either do not modify the parent cephalosporin or are insufficiently inhibited by the inhibitor.
[A] The addition of a beta-lactamase inhibitor does not add clinical benefit.The beta-lactamases produced by the organisms either do not modify the parent cephalosporin or are insufficiently inhibited by the inhibitor.
[2] 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/.
[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.
[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/.
[2] The in vitro activity of cefiderocol against Stenotrophomonas maltophilia is comparable to the activity of the agent against Enterobacterales and there is also animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥28 mm) are mostly devoid of resistance mechanisms. Isolates with MICs 1-2 mg/L have acquired resistance mechanisms which may result in impaired clinical response. Isolates with MIC values >2 mg/L (zone diameter <22 mm) will likely be resistant. | [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] The in vitro activity of cefiderocol against Stenotrophomonas maltophilia is comparable to the activity of the agent against Enterobacterales and there is also animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥28 mm) are mostly devoid of resistance mechanisms. Isolates with MICs 1-2 mg/L have acquired resistance mechanisms which may result in impaired clinical response. Isolates with MIC values >2 mg/L (zone diameter <22 mm) will likely be resistant. | [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/.
[1] Fluoroquinolones have been used in combination therapy. The ECOFF can be used to exclude acquired resistance mechanisms.
[A] Disk diffusion criteria are not available.
[1] Fluoroquinolones have been used in combination therapy. The ECOFF can be used to exclude acquired resistance mechanisms.
[A] Disk diffusion criteria are not available.
[1] Tetracyclines have been used in combination therapy. The ECOFF can be used to exclude acquired resistance mechanisms. | [2] Pertains to intravenous therapy. Oral therapy will lead to insufficient exposure.
[A] Disk diffusion criteria are not available.
[1] Tetracyclines have been used in combination therapy. The ECOFF can be used to exclude acquired resistance mechanisms.
[A] Disk diffusion criteria are not available.
[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.
[2] The in vitro activity of cefiderocol against Acinetobacter spp. is comparable to the activity of the agent against Enterobacterales and there is also animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥21 mm) are mostly devoid of resistance mechanisms. Isolates with MICs 1-2 mg/L have acquired resistance mechanisms which may result in impaired clinical response. Isolates with MIC values >2 mg/L (zone diameter <17 mm) will likely be resistant. | [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] The in vitro activity of cefiderocol against Acinetobacter spp. is comparable to the activity of the agent against Enterobacterales and there is also animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥21 mm) are mostly devoid of resistance mechanisms. Isolates with MICs 1-2 mg/L have acquired resistance mechanisms which may result in impaired clinical response. Isolates with MIC values >2 mg/L (zone diameter <17 mm) will likely be resistant. | [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/.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor.
[1/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor.
[1/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor.
[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] Minocycline has been discussed as alternative therapy in Acinetobacter infections. The “IE” in the table pertains to intravenous therapy only. Oral administration will not accomplish sufficient exposure.
[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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/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 7/D and 9/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 7/D and 9/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 7/D and 9/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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/F. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
4.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 7/D and 9/F. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
4.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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/F. | [2] See table of dosages.
[5] 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 7/D and 9/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] 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 7/D and 9/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.
[6] 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 7/D and 9/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 7/D and 9/F.
[7] 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.
[7] 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.
[9] 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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/F. | [2] See table of dosages.
[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 7/D and 9/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 7/D and 9/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. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[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. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] 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] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[2] 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] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C] A disk diffusion test awaits action from the responsible pharmaceutical company.
[C] 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
[3] 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.
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note | [3] 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.
[3] 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.
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note | [3] 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]  | [D] Isolates categorised as screen negative can be reported susceptible to moxifloxacin and "susceptible increased exposure" (I) to levofloxacin. For ciprofloxacin, the isolate is without phenotypically detectable resistance mechanisms and can be used in high exposure in combination therapy (see Note 2/A). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[3] 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.
[E] 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/.
[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/.
[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.
[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.
[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.
[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.
[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.
[A] For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test.
[1] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[B] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[1] Susceptibility can be inferred from ampicillin.
[B] Susceptibility can be inferred from ampicillin.
[1] Susceptibility can be inferred from ampicillin.
[B] Susceptibility can be inferred from ampicillin.
[3] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and the specified agents can be used in high exposure in combination therapy (see Note 4/D). Isolates resistant to ampicillin can be reported resistant. | [4] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[C] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and the specified agents can be used in high exposure in combination therapy (see Note 4/D). Isolates resistant to ampicillin can be reported resistant. | [D] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[B] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[1] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[B] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[3] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and the specified agents can be used in high exposure in combination therapy (see Note 4/D). Isolates resistant to ampicillin can be reported resistant. | [4] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[C] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and the specified agents can be used in high exposure in combination therapy (see Note 4/D). Isolates resistant to ampicillin can be reported resistant. | [D] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[5] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[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 byEnterococcus faecalis 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 acquired resistance has been 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 byEnterococcus faecalis 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 acquired resistance has been 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 the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[3] Isolates screening positive with gentamicin for aminoglycoside-modifying enzymes may still exhibit synergy with streptomycin. This can be screened for with streptomycin testing.
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and 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. Combinations between penicillins or glycopeptides and streptomycin will not be synergistic.
[B] Isolates screening positive with gentamicin for aminoglycoside-modifying enzymes may still exhibit synergy with streptomycin. This can be screened for with streptomycin testing.
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and 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. Combinations between penicillins or glycopeptides and streptomycin will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Vancomycin susceptible E. faecalis and E. faecium 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.
[1] For more information, see https://www.eucast.org/eucastguidancedocuments/.
[1] For more information, see https://www.eucast.org/eucastguidancedocuments/.
[2] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[A] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[3] 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.
[B] 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.
[4] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. Isolates with MICs >1 mg/L most likely have resistance mechanisms against trimethoprim and trimethoprim-sulfamethoxazole. For E. faecalis and E. faecium this corresponds to a zone diameter <21 mm for trimethoprim and <23 mm for trimethoprim-sulfamethoxazole.
[C] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. Isolates with MICs >1 mg/L most likely have resistance mechanisms against trimethoprim and trimethoprim-sulfamethoxazole. For E. faecalis and E. faecium this corresponds to a zone diameter <21 mm for trimethoprim and <23 mm for trimethoprim-sulfamethoxazole.
[4] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. Isolates with MICs >1 mg/L most likely have resistance mechanisms against trimethoprim and trimethoprim-sulfamethoxazole. For E. faecalis and E. faecium this corresponds to a zone diameter <21 mm for trimethoprim and <23 mm for trimethoprim-sulfamethoxazole. | [5] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[C] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. Isolates with MICs >1 mg/L most likely have resistance mechanisms against trimethoprim and trimethoprim-sulfamethoxazole. For E. faecalis and E. faecium this corresponds to a zone diameter <21 mm for trimethoprim and <23 mm for trimethoprim-sulfamethoxazole. | [5] 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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.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.
[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 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 manufacturers' 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 manufacturers' 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 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.
[3] The activity of trimethoprim is uncertain against S. agalactiae and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type is 2 mg/L.
[B] The activity of trimethoprim is uncertain against S. agalactiae and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type is 2 mg/L.
[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.
[A] Read and interpret the benzylpenicillin disk only for isolates with oxacillin 1 µg zone diameters <20 mm. If benzylpenicillin zone ≥14 mm, report benzylpenicillin “susceptible, increased exposure” (I), If zone <14 mm, report benzylpenicillin resistant (R), see flow chart below. | [B] 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] 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] 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis).
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis).
[B] 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] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis).
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] 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.
[B] 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.
[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 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.
[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] 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.
[2] 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/.
[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. | [4] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [C] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [C] 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. | [D] Susceptibility can be inferred from the benzylpenicillin screen test or from "Ampicillin iv (endocarditis)".
[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. | [4] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [C] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [4] 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. | [C] 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. | [4] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [C] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3] 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.
[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. | [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.
[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 acquired resistance has been 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 acquired resistance has been excluded, the isolate should be reported “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[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 manufacturers' 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 manufacturers' 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] Linezolid 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 >2 mg/L) should be excluded. When excluded, the isolate should be reported “devoid of linezolid resistance mechanisms”, but not as susceptible to linezolid.
[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.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent cephalosporin or are not affected by the inhibitor.
[2/D] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent cephalosporin or are not affected by the inhibitor.
[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.
[3] 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. | [3] 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 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 addition of the beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[3/E] The addition of the beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[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. | [D] For benzylpenicillin screen positive isolates (zone <12 mm), determine the MIC in meningitis.
[3] The addition of the beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[3/E] The addition of the beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent cephalosporin or are not affected by the inhibitor.
[1/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent cephalosporin or are not affected by the inhibitor.
[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 addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[2/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[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 addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[2/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[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 a 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 a 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 sulbactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [3] Isolates susceptible to ampicillin-sulbactam and amoxicillin-clavulanic acid may be resistant to piperacillin-tazobactam.
[3] Isolates susceptible to ampicillin-sulbactam and amoxicillin-clavulanic acid may be resistant to piperacillin-tazobactam.
[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.
[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] 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] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported "susceptible, increased exposure” (I) to cefotaxime. Isolates resistant to benzylpenicillin should be tested for susceptibility to cefotaxime or reported resistant.
[A] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported "susceptible, increased exposure” (I) to cefotaxime. Isolates resistant to benzylpenicillin should be tested for susceptibility to cefotaxime or reported resistant.
[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] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[A] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline 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] 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] Susceptibility can be inferred from benzylpenicillin susceptibility.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Susceptibility can be inferred from benzylpenicillin susceptibility.
[3] The in vitro antimicrobial activity of the fixed concentration of 2 mg/L for clavulanic acid 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.
[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.
[2] The in vitro activity of cefiderocol against Achromobacter xylosoxidans is comparable to the activity of the agent against Enterobacterales and there is also animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥26 mm) are mostly devoid of resistance mechanisms. Isolates with MICs 1-2 mg/L have acquired resistance mechanisms which may result in impaired clinical response. Isolates with MIC values >2 mg/L (zone diameter <22 mm) will likely be resistant. | [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] The in vitro activity of cefiderocol against Achromobacter xylosoxidans is comparable to the activity of the agent against Enterobacterales and there is also animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥26 mm) are mostly devoid of resistance mechanisms. Isolates with MICs 1-2 mg/L have acquired resistance mechanisms which may result in impaired clinical response. Isolates with MIC values >2 mg/L (zone diameter <22 mm) will likely be resistant. | [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/.
[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] 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] 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] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[A] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[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/.
[1] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[A] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[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/. | [B] Examine zones carefully for colonies close to the zone edge. Colonies should be taken into account when reading.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[C] Read the obvious zone edges and disregard haze or faint growth within the inhibition zone. | [2] 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] 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 not determined with the EUCAST reference method. Therefore they are provisory values that might change according to the results on ongoing studies using the EUCAST reference protocol for MIC determination.
[1] Breakpoints were not determined with the EUCAST reference method. Therefore they are provisory values that might change according to the results on ongoing studies using the EUCAST reference protocol for MIC determination.
[1] Breakpoints were not determined with the EUCAST reference method. Therefore they are provisory values that might change according to the results on ongoing studies using the EUCAST reference protocol for MIC determination. | [2] A provisional screen value of 2 mg/L is advised according to published MIC data determined with MGIT.
[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 decolonization in carriers of S. aureus, S ≤1, R >1 mg/L (disk diffusion with mupirocin 200 µg disk S ≥30, R <30 mm). For short term suppression of nasal colonization (usually as a perioperative practice) breakpoints of S ≤256, R >256 mg/L (disk diffusion S ≥18 mm, R <18 mm) can be used.
[2] Breakpoints for nasal decolonization in carriers of S. aureus, S ≤1, R >1 mg/L (disk diffusion with mupirocin 200 µg disk S ≥30, R <30 mm). For short term suppression of nasal colonization (usually as a perioperative practice) breakpoints of S ≤256, R >256 mg/L (disk diffusion S ≥18 mm, R <18 mm) can be used.
[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] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and "amoxicillin oral (other indications)" can be used in high exposure in combination therapy (see Note 3/D). Isolates resistant to ampicillin can be reported resistant. | [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] For susceptibility testing purposes, the concentration of enmetazobactam is fixed at 8 mg/L.
[4] 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/.
[5] 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] 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.
[6] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[8] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [7] See table of dosages for dosing for different indications.
[7] 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.
[2] For susceptibility testing purposes, the concentration of avibactam is fixed at 4 mg/L.
[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/.
[1] Azithromycin has been used in the treatment of enteric infections, primarily with Salmonella Typhi and Shigella species and although wild type distributions vary somewhat, isolates with MICs above 16 mg/L (azithromycin 15 µg disk zone diameters <12 mm) are likely to have azithromycin resistance mechanisms.
[1/A] Azithromycin has been used in the treatment of enteric infections, primarily with Salmonella Typhi and Shigella species and although wild type distributions vary somewhat, isolates with MICs above 16 mg/L (azithromycin 15 µg disk zone diameters <12 mm) are likely to have azithromycin resistance mechanisms. | [B] When reading azithromycin zone diameters, take growth appearing as a thin inner zone on some batches of Mueller-Hinton agar into account.
[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 (presence of resistance indicated by 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 (presence of resistance indicated by 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] For Proteus spp., there is insufficient clinical evidence of efficacy. The ECOFF can be used to exclude acquired resistance mechanisms (presence of resistance indicated by MICs >8 mg/L or trimethoprim 5 µg disk zone diameter <14 mm).
[G] For Proteus spp., there is insufficient clinical evidence of efficacy. The ECOFF can be used to exclude acquired resistance mechanisms (presence of resistance indicated by MICs >8 mg/L or trimethoprim 5 µg disk zone diameter <14 mm).
[8] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[8] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[8] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[8] 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] The addition of a beta-lactamase inhibitor does not add clinical benefit.The beta-lactamases produced by the organisms either do not modify the parent cephalosporin or are insufficiently inhibited by the inhibitor.
[A] The addition of a beta-lactamase inhibitor does not add clinical benefit.The beta-lactamases produced by the organisms either do not modify the parent cephalosporin or are insufficiently inhibited by the inhibitor.
[2] 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/.
[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.
[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/.
[2] The in vitro activity of cefiderocol against Stenotrophomonas maltophilia is comparable to the activity of the agent against Enterobacterales and there is animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥28 mm) are mostly devoid of resistance mechanisms and are likely to be a target for treatment with this agent. Isolates with MICs 1-2 mg/L have some acquired resistance mechanisms. Little clinical data exists regarding clinical outcome for these isolates, however, they may still be a target for treatment with this agent if there are limited treatment options. Isolates with MIC values >2 mg/L (zone diameter <22 mm) have acquired resistance mechanisms and are likely to be resistant to this agent. | [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] The in vitro activity of cefiderocol against Stenotrophomonas maltophilia is comparable to the activity of the agent against Enterobacterales and there is animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥28 mm) are mostly devoid of resistance mechanisms and are likely to be a target for treatment with this agent. Isolates with MICs 1-2 mg/L have some acquired resistance mechanisms. Little clinical data exists regarding clinical outcome for these isolates, however, they may still be a target for treatment with this agent if there are limited treatment options. Isolates with MIC values >2 mg/L (zone diameter <22 mm) have acquired resistance mechanisms and are likely to be resistant to this agent. | [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/.
[1] The ECOFF can be used to exclude acquired resistance mechanisms (presence of resistance indicated by MICs >8 mg/L or aztreonam-avibactam 30-20 µg disk zone diameter <21 mm).
[A] The ECOFF can be used to exclude acquired resistance mechanisms (presence of resistance indicated by MICs >8 mg/L or aztreonam-avibactam 30-20 µg disk zone diameter <21 mm).
[1] Fluoroquinolones have been used in combination therapy. The ECOFF can be used to exclude acquired resistance mechanisms.
[A] Disk diffusion criteria are not available.
[1] Fluoroquinolones have been used in combination therapy. The ECOFF can be used to exclude acquired resistance mechanisms.
[A] Disk diffusion criteria are not available.
[1] Tetracyclines have been used in combination therapy. The ECOFF can be used to exclude acquired resistance mechanisms. | [2] Pertains to intravenous therapy. Oral therapy will lead to insufficient exposure.
[A] Disk diffusion criteria are not available.
[1] Tetracyclines have been used in combination therapy. The ECOFF can be used to exclude acquired resistance mechanisms.
[A] Disk diffusion criteria are not available.
[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.
[2] The in vitro activity of cefiderocol against Acinetobacter baumannii group is comparable to the activity of the agent against Enterobacterales and there is animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥21 mm) are mostly devoid of resistance mechanisms and are likely to be a target for treatment with this agent. Isolates with MICs 1-2 mg/L have some acquired resistance mechanisms. Little clinical data exists regarding clinical outcome for these isolates, however, they may still be a target for treatment with this agent if there are limited treatment options. Isolates with MIC values >2 mg/L (zone diameter <17 mm) have acquired resistance mechanisms and are likely to be resistant to this agent. | [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] The in vitro activity of cefiderocol against Acinetobacter baumannii group is comparable to the activity of the agent against Enterobacterales and there is animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥21 mm) are mostly devoid of resistance mechanisms and are likely to be a target for treatment with this agent. Isolates with MICs 1-2 mg/L have some acquired resistance mechanisms. Little clinical data exists regarding clinical outcome for these isolates, however, they may still be a target for treatment with this agent if there are limited treatment options. Isolates with MIC values >2 mg/L (zone diameter <17 mm) have acquired resistance mechanisms and are likely to be resistant to this agent. | [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/.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor.
[1/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor.
[1] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor.
[1/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organisms either do not modify the parent carbapenem or are insufficiently inhibited by the inhibitor.
[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] Minocycline has been discussed as alternative therapy in Acinetobacter infections. The “IE” in the table pertains to intravenous therapy only. Oral administration will not accomplish sufficient exposure.
[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, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
4.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, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
4.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, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[5] 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, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/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] 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, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/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.
[6] 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, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F.
[7] 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.
[7] 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.
[9] 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, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F. | [2] See table of dosages.
[1] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/F.
[A] Susceptibility of staphylococci to cephalosporins is inferred from the cefoxitin susceptibility except for cefixime, ceftazidime, ceftazidime-avibactam, ceftibuten, cefiderocol 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 cefazolin, cefepime, cefotaxime, ceftriaxone or cefuroxime iv are reported for methicillin-susceptible staphylococci, these should be reported “susceptible, increased exposure” (I) - see https://www.eucast.org/eucastguidancedocuments/. Many methicillin-resistant S. aureus are susceptible to ceftaroline and ceftobiprole, see Notes 7/D and 9/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. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[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. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[A] Susceptibility of staphylococci to carbapenems is inferred from the cefoxitin susceptibility. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[2] 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] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[2] 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] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note
[C] A disk diffusion test awaits action from the responsible pharmaceutical company.
[C] 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
[3] 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.
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note | [3] 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.
[3] 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.
[B] The norfloxacin disk diffusion test can be used to screen for fluoroquinolone resistance. See Note | [3] 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]  | [D] Isolates categorised as screen negative can be reported susceptible to moxifloxacin and "susceptible increased exposure" (I) to levofloxacin. For ciprofloxacin, the isolate is without phenotypically detectable resistance mechanisms and can be used in high exposure in combination therapy (see Note 2/A). Isolates categorised as screen positive should be tested for susceptibility to individual agents or reported resistant.
[3] 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.
[E] 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/.
[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/.
[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.
[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.
[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.
[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.
[3] For other staphylococci, the ECOFF can be used to exclude acquired resistance mechanisms, see https://www.eucast.org/eucastguidancedocuments/.
[A] Use an MIC method.
[4] 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/.
[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.
[A] For E. faecalis that test resistant to ampicillin with disk diffusion, confirm with an MIC test.
[1] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[B] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[1] Susceptibility can be inferred from ampicillin.
[B] Susceptibility can be inferred from ampicillin.
[1] Susceptibility can be inferred from ampicillin.
[B] Susceptibility can be inferred from ampicillin.
[3] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and the specified agents can be used in high exposure in combination therapy (see Note 4/D). Isolates resistant to ampicillin can be reported resistant. | [4] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[C] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and the specified agents can be used in high exposure in combination therapy (see Note 4/D). Isolates resistant to ampicillin can be reported resistant. | [D] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/.
[1] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[B] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[1] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[B] Susceptibility can be inferred from ampicillin. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[3] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and the specified agents can be used in high exposure in combination therapy (see Note 4/D). Isolates resistant to ampicillin can be reported resistant. | [4] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[C] Isolates susceptible to ampicillin are without phenotypically detectable resistance mechanisms and the specified agents can be used in high exposure in combination therapy (see Note 4/D). Isolates resistant to ampicillin can be reported resistant. | [D] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[5] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit. Beta-lactamase producing enterococci are extremely rare.
[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 faecalis There are no clinical breakpoints but acquired resistance (indicated by MIC >1 mg/L) should be excluded. The norfloxacin disk diffusion screen test can be used to exclude resistance mechanisms. When acquired resistance has been 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 faecalis There are no clinical breakpoints but acquired resistance (indicated by MIC >1 mg/L) should be excluded. The norfloxacin disk diffusion screen test can be used to exclude resistance mechanisms. When acquired resistance has been 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 the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[3] Isolates screening positive with gentamicin for aminoglycoside-modifying enzymes may still exhibit synergy with streptomycin. This can be screened for with streptomycin testing.
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and 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. Combinations between penicillins or glycopeptides and streptomycin will not be synergistic.
[B] Isolates screening positive with gentamicin for aminoglycoside-modifying enzymes may still exhibit synergy with streptomycin. This can be screened for with streptomycin testing.
Negative test: Isolates with streptomycin MIC ≤512 mg/L or a zone diameter ≥14 mm. The isolate is wild type for streptomycin and 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. Combinations between penicillins or glycopeptides and streptomycin will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L or a zone diameter ≥8 mm. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, synergy with penicillins or glycopeptides can be expected if the isolate is susceptible to the penicillin or glycopeptide. For other aminoglycosides, this may not be the case. 
Positive test: Isolates with gentamicin MIC >128 mg/L or a zone diameter <8 mm denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic, except streptomycin which must be tested separately if required (see note 3/B).
[A] Vancomycin susceptible E. faecalis and E. faecium 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.
[1] For more information, see https://www.eucast.org/eucastguidancedocuments/.
[1] For more information, see https://www.eucast.org/eucastguidancedocuments/.
[2] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[A] Antimicrobial susceptibility testing is discouraged. For information on the use of fosfomycin iv in combination therapy, see https://www.eucast.org/eucastguidancedocuments/.
[3] 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.
[B] 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.
[4] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. Isolates with MICs >1 mg/L most likely have resistance mechanisms against trimethoprim and trimethoprim-sulfamethoxazole. For E. faecalis and E. faecium this corresponds to a zone diameter <21 mm for trimethoprim and <23 mm for trimethoprim-sulfamethoxazole.
[C] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. Isolates with MICs >1 mg/L most likely have resistance mechanisms against trimethoprim and trimethoprim-sulfamethoxazole. For E. faecalis and E. faecium this corresponds to a zone diameter <21 mm for trimethoprim and <23 mm for trimethoprim-sulfamethoxazole.
[4] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. Isolates with MICs >1 mg/L most likely have resistance mechanisms against trimethoprim and trimethoprim-sulfamethoxazole. For E. faecalis and E. faecium this corresponds to a zone diameter <21 mm for trimethoprim and <23 mm for trimethoprim-sulfamethoxazole. | [5] Trimethoprim-sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[C] The activity of trimethoprim and trimethoprim-sulfamethoxazole is uncertain against enterococci, and it is not possible to predict clinical outcome. Isolates with MICs >1 mg/L most likely have resistance mechanisms against trimethoprim and trimethoprim-sulfamethoxazole. For E. faecalis and E. faecium this corresponds to a zone diameter <21 mm for trimethoprim and <23 mm for trimethoprim-sulfamethoxazole. | [5] 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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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 with the exception of phenoxymethylpenicillin and isoxazolylpenicillins for streptococcus group B, where there is insufficient evidence for clinical efficacy.
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.
[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 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 manufacturers' 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 manufacturers' 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 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.
[3] The activity of trimethoprim is uncertain against S. agalactiae and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type is 2 mg/L.
[B] The activity of trimethoprim is uncertain against S. agalactiae and it is not possible to predict clinical outcome. The ECOFF to categorise isolates as wild type or non-wild type is 2 mg/L.
[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.
[A] Read and interpret the benzylpenicillin disk only for isolates with oxacillin 1 µg zone diameters <20 mm. If benzylpenicillin zone ≥14 mm, report benzylpenicillin “susceptible, increased exposure” (I), If zone <14 mm, report benzylpenicillin resistant (R), see flow chart below. | [B] 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] 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] 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis).
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis).
[B] 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] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[4] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis).
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and 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. | [3] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[B] 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] Susceptibility inferred from ampicillin (indications other than endocarditis and meningitis). | [2] 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.
[B] 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.
[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 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.
[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] 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 (presence of resistance indicated by 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 (presence of resistance indicated by 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.
[2] 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/.
[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. | [4] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [C] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [C] 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. | [D] Susceptibility can be inferred from the benzylpenicillin screen test or from "Ampicillin iv (endocarditis)".
[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. | [4] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [C] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [4] 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. | [C] 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. | [4] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] 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. | [C] For benzylpenicillin screen negative isolates, susceptibility can be inferred from benzylpenicillin or ampicillin. For benzylpenicillin screen positive isolates, susceptibility is inferred from ampicillin. | [3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3] The addition of a beta-lactamase inhibitor does not add clinical benefit.
[3] 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.
[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. | [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.
[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 (indicated by MIC >0.5 mg/L; zone diameter <21 mm for the moxifloxacin 5 µg disk) should be excluded. When acquired resistance has been 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 (indicated by MIC >0.5 mg/L; zone diameter <21 mm for the moxifloxacin 5 µg disk) should be excluded. When acquired resistance has been excluded, the isolate should be reported “devoid of fluoroquinolone resistance mechanisms”, but not as susceptible to moxifloxacin.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[2] Gentamicin can be used to screen for the presence of aminoglycoside-modifying enzymes (high-level aminoglycoside resistance).
Negative test: Isolates with gentamicin MIC ≤128 mg/L. The isolate is wild type for gentamicin (i.e. does not contain aminoglycoside-modifying enzymes). Therefore, 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 denote presence of aminoglycoside-modifying enzymes. Combinations between penicillins or glycopeptides and aminoglycosides will not be synergistic.
[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 manufacturers' 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 manufacturers' 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] Linezolid has been used in oral follow-up treatment of endocarditis caused by viridans group streptococci. There are no clinical breakpoints but acquired resistance (indicated by MIC >2 mg/L) should be excluded. When excluded, the isolate should be reported “devoid of linezolid resistance mechanisms”, but not as susceptible to linezolid.
[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 (indicated by 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 (indicated by 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.
[3] In meningitis, H. influenzae negative in the benzylpenicillin 1 unit screen (zone diameter ≥12 mm) can be reported susceptible. | [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.
[C] In meningitis, H. influenzae negative in the benzylpenicillin 1 unit screen (zone diameter ≥12 mm) can be reported susceptible. | [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.
[4] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L. | [5] 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.
[3] In meningitis, H. influenzae negative in the benzylpenicillin 1 unit screen (zone diameter ≥12 mm) can be reported susceptible. | [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.
[C] In meningitis, H. influenzae negative in the benzylpenicillin 1 unit screen (zone diameter ≥12 mm) can be reported susceptible. | [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.
[6] 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.
[6] 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.
[7] 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.
[2] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent cephalosporin or are not affected by the inhibitor.
[2/D] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent cephalosporin or are not affected by the inhibitor.
[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.
[3] 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. | [3] 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 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 addition of the beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[3/E] The addition of the beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[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. | [D] For benzylpenicillin screen positive isolates (zone <12 mm), determine the MIC in meningitis.
[3] The addition of the beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[3/E] The addition of the beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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 and erythromycin 16 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] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent cephalosporin or are not affected by the inhibitor.
[1/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent cephalosporin or are not affected by the inhibitor.
[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 addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[2/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[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 addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[2/A] The addition of a beta-lactamase inhibitor does not add clinical benefit. The beta-lactamases produced by the organism either do not modify the parent carbapenem or are not affected by the inhibitor.
[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 a 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 a 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 sulbactam is fixed at 4 mg/L.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[4] For susceptibility testing purposes, the concentration of tazobactam is fixed at 4 mg/L. | [3] Isolates susceptible to ampicillin-sulbactam and amoxicillin-clavulanic acid may be resistant to piperacillin-tazobactam.
[3] Isolates susceptible to ampicillin-sulbactam and amoxicillin-clavulanic acid may be resistant to piperacillin-tazobactam.
[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.
[6] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[C] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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.
[3] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[D] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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. | [3] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L. | [4] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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. | [5] 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. | [4] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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. | [5] 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.
[6] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[D] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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.
[5] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[D] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[1] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[A] Susceptibility can be inferred from ampicillin.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[3] For susceptibility testing purposes, the concentration of  tazobactam is fixed at 4 mg/L.
[4] 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.
[5] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[D] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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.
[5] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[C] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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. | [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.
[5] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[D] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[1] For susceptibility testing purposes, the concentration of sulbactam is fixed at 4 mg/L.
[A] Susceptibility can be inferred from ampicillin.
[2] For susceptibility testing purposes, the concentration of clavulanic acid is fixed at 2 mg/L.
[3] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[B] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed. | [2] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed. | [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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed. | [2] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed. | [2] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[3] Susceptibility to ceftriaxone can be inferred from the cefotaxime disk diffusion test.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed. | [3] Susceptibility to ceftriaxone can be inferred from the cefotaxime disk diffusion test.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed. | [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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[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. Resistance to beta-lactam agents in C. acnes is rare. The identification and antimicrobial susceptibility test result on any such isolate must be confirmed.
[D] 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.
[5] Susceptibility to ceftriaxone can be inferred from the cefotaxime disk diffusion test.
[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. | [5] Susceptibility to ceftriaxone can be inferred from the cefotaxime disk diffusion test.
[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] 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.
[5] Inducible clindamycin resistance may occur. This can be detected by antagonism of clindamycin activity by a macrolide agent [erythromycin and clindamycin disks 12-16 mm apart (edge to edge)]. The clinical significance is unknown.
[C] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading. | [5] Inducible clindamycin resistance may occur. This can be detected by antagonism of clindamycin activity by a macrolide agent [erythromycin and clindamycin disks 12-16 mm apart (edge to edge)]. The clinical significance is unknown.
[6] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[D] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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.
[4] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [3] Inducible clindamycin resistance may occur. This can be detected by antagonism of clindamycin activity by a macrolide agent [erythromycin and clindamycin disks 12-16 mm apart (edge to edge)]. The clinical significance is unknown.
[C] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [D] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading. | [3] Inducible clindamycin resistance may occur. This can be detected by antagonism of clindamycin activity by a macrolide agent [erythromycin and clindamycin disks 12-16 mm apart (edge to edge)]. The clinical significance is unknown.
[5] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[E] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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.
[6] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [5] Inducible clindamycin resistance may occur. This can be detected by antagonism of clindamycin activity by a macrolide agent [erythromycin and clindamycin disks 12-16 mm apart (edge to edge)]. The clinical significance is unknown.
[C] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [D] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading. | [5] Inducible clindamycin resistance may occur. This can be detected by antagonism of clindamycin activity by a macrolide agent [erythromycin and clindamycin disks 12-16 mm apart (edge to edge)]. The clinical significance is unknown.
[7] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[E] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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] The in vitro antimicrobial activity of the fixed concentration of the inhibitor 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.
[4] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [3] Inducible clindamycin resistance may occur. This can be detected by antagonism of clindamycin activity by a macrolide agent [erythromycin and clindamycin disks 12-16 mm apart (edge to edge)]. The clinical significance is unknown.
[C] For information on how to use breakpoints in brackets, see https://www.eucast.org/eucastguidancedocuments/. | [D] Examine zones carefully for colonies within zones. Colonies should be taken into account when reading. | [3] Inducible clindamycin resistance may occur. This can be detected by antagonism of clindamycin activity by a macrolide agent [erythromycin and clindamycin disks 12-16 mm apart (edge to edge)]. The clinical significance is unknown.
[5] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[E] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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] 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] 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] Metronidazole resistance is rare, but inadequate anaerobic conditions may lead to false resistance. In case of resistance, confirm sufficient anaerobicity, species identification and antimicrobial susceptibility test result.
[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] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported "susceptible, increased exposure” (I) to cefotaxime. Isolates resistant to benzylpenicillin should be tested for susceptibility to cefotaxime or reported resistant.
[A] Isolates "susceptible, increased exposure” (I) to benzylpenicillin can be reported "susceptible, increased exposure” (I) to cefotaxime. Isolates resistant to benzylpenicillin should be tested for susceptibility to cefotaxime or reported resistant.
[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] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[A] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline 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] 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] Susceptibility can be inferred from benzylpenicillin susceptibility.
[2] Susceptibility can be inferred from benzylpenicillin susceptibility.
[A] Susceptibility can be inferred from benzylpenicillin susceptibility.
[3] The in vitro antimicrobial activity of the fixed concentration of 2 mg/L for clavulanic acid 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.
[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.
[2] The in vitro activity of cefiderocol against Achromobacter xylosoxidans is comparable to the activity of the agent against Enterobacterales and there is animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥26 mm) are mostly devoid of resistance mechanisms and are likely to be a target for treatment with this agent. Isolates with MICs 1-2 mg/L have some acquired resistance mechanisms. Little clinical data exists regarding clinical outcome for these isolates, however, they may still be a target for treatment with this agent if there are limited treatment options. Isolates with MIC values >2 mg/L (zone diameter <22 mm) have acquired resistance mechanisms and are likely to be resistant to this agent. | [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] The in vitro activity of cefiderocol against Achromobacter xylosoxidans is comparable to the activity of the agent against Enterobacterales and there is animal data to suggest efficacy. However, there is insufficient clinical data to determine a clinical breakpoint. Isolates with MIC values ≤0.5 mg/L (zone diameter ≥26 mm) are mostly devoid of resistance mechanisms and are likely to be a target for treatment with this agent. Isolates with MICs 1-2 mg/L have some acquired resistance mechanisms. Little clinical data exists regarding clinical outcome for these isolates, however, they may still be a target for treatment with this agent if there are limited treatment options. Isolates with MIC values >2 mg/L (zone diameter <22 mm) have acquired resistance mechanisms and are likely to be resistant to this agent. | [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/.
[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] 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] 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] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[A] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[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/.
[1] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[A] Isolates susceptible to tetracycline can be reported susceptible to doxycycline. Isolates resistant to tetracycline should be tested for susceptibility to doxycycline or reported resistant.
[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/. | [B] Examine zones carefully for colonies close to the zone edge. Colonies should be taken into account when reading.
[2] Trimethoprim:sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as the trimethoprim concentration.
[C] Read the obvious zone edges and disregard haze or faint growth within the inhibition zone. | [2] 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] 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] For bedaquiline, breakpoints were determined using the EUCAST reference method.
[2] For delamanid and pretomanid, breakpoints were not determined with the EUCAST reference method. Therefore they are provisional and might change according to the results of future studies with the EUCAST reference method for MIC determination.
3.The provisional breakpoint was determined according to MIC data determined with the agar dilution and the agar proportion methods.
[2] For delamanid and pretomanid, breakpoints were not determined with the EUCAST reference method. Therefore they are provisional and might change according to the results of future studies with the EUCAST reference method for MIC determination.
3.The provisional breakpoint was determined according to MIC data determined with the agar dilution and the agar proportion methods. | [4] A provisional screen value of 2 mg/L is advised according to published MIC data determined with MGIT.
[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 decolonization in carriers of S. aureus, S ≤1, R >1 mg/L (disk diffusion with mupirocin 200 µg disk S ≥30, R <30 mm). For short term suppression of nasal colonization (usually as a perioperative practice) breakpoints of S ≤256, R >256 mg/L (disk diffusion S ≥18 mm, R <18 mm) can be used.
[2] Breakpoints for nasal decolonization in carriers of S. aureus, S ≤1, R >1 mg/L (disk diffusion with mupirocin 200 µg disk S ≥30, R <30 mm). For short term suppression of nasal colonization (usually as a perioperative practice) breakpoints of S ≤256, R >256 mg/L (disk diffusion S ≥18 mm, R <18 mm) can be used.
[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).