2013 Interpretive Criteria for Neisseria gonorrhoeae Susceptibility Testing
The following are zone diameter interpretive standards and equivalent minimal inhibitory concentration (MIC) breakpoints* for Neisseria gonorrhoeae according to the Clinical and Laboratory Standards Institute (Performance Standards for Antimicrobial Susceptibility Testing; Twenty-Third Informational Supplement, January 2013, M100-S23 Vol 33 No 1:
*At this time, no interpretive criteria exists for Azithromycin and Levofloxacin
| Penicillins | Zone Diameter (nearest whole mm) |
Equivalent MIC Breakpoints (µg/mL) |
|||
|---|---|---|---|---|---|
| R | I | S | R | S | |
| Penicillin | <=26 | 27-46 | >=47 | >=2 | <=0.06 |
| Cephems (Parenteral) | Zone Diameter (nearest whole mm) |
Equivalent MIC Breakpoints (µg/mL) |
|||
|---|---|---|---|---|---|
| R | I | S | R | S | |
| Cefotaxime | – | – | >=31 | – | <=0.5 |
| Ceftizoxime | – | – | >=38 | – | <=0.5 |
| Ceftriaxone | – | – | >=35 | – | <=0.25 |
| Cefmetazole | <=27 | 28-32 | >=33 | >=8 | <=2 |
| Cefotetan | <=19 | 20-25 | >=26 | >=8 | <=2 |
| Cefoxitin | <=23 | 24-27 | >=28 | >=8 | <=2 |
| Cefuroxime sodium (parenteral) | <=25 | 26-30 | >=31 | >=4 | <=1 |
| Cefepime | – | – | >=31 | – | <=0.5 |
| Ceftazidime | – | – | >=31 | – | <=0.5 |
| Cephems (Oral) | Zone Diameter (nearest whole mm) |
Equivalent MIC Breakpoints (µg/mL) |
|||
|---|---|---|---|---|---|
| R | I | S | R | S | |
| Cefixime | – | – | >=31 | – | <=0.25 |
| Cefpodoxime | – | – | >=29 | – | <=0.5 |
| Cefetamet | – | – | >=29 | – | <=0.5 |
| Tetracyclines | Zone Diameter (nearest whole mm) |
Equivalent MIC Breakpoints (µg/mL) |
|||
|---|---|---|---|---|---|
| R | I | S | R | S | |
| Tetracycline | <=30 | 31-37 | >=38 | >=2 | <=0.25 |
| Fluoroquinolones | Zone Diameter (nearest whole mm) |
Equivalent MIC Breakpoints (µg/mL) |
|||
|---|---|---|---|---|---|
| R | I | S | R | S | |
| Ciprofloxacin | <=27 | 28-40 | >=41 | >=1 | <=0.06 |
| Gatifloxacin | <=33 | 34-37 | >=38 | >=0.5 | <=0.12 |
| Ofloxacin | <=24 | 25-30 | >=31 | >=2 | <=0.25 |
| Enoxacin | <=31 | 32-35 | >=36 | >=2 | <=0.5 |
| Grepafloxacin | <=27 | 28-36 | >=37 | >=1 | <=0.06 |
| Lomefloxacin | <=26 | 27-37 | >=38 | >=2 | <=0.12 |
| Trovafloxacin | – | – | >=34 | – | <=0.25 |
| Fleroxacin | <=28 | 29-34 | >=35 | >=1 | <=0.25 |
| Aminocyclitols | Zone Diameter (nearest whole mm) |
Equivalent MIC Breakpoints (µg/mL) |
|||
|---|---|---|---|---|---|
| R | I | S | R | S | |
| Spectinomycin | <=14 | 15-17 | >=18 | >=128 | <=32 |