Volume 3, Number 1—March 1997
Synopsis
Fluoroquinolone Resistance in Neisseria gonorrhoeae
Table
Criteria for interpreting susceptibilities of Neisseria gonorrhoeae strains to the fluoroquinolones ciprofloxacin, ofloxacin, enoxacin, lomefloxacin, and norfloxacina,b
| Therapeutic agent,
Dose |
Agent Tested,
Disk Content |
Zone Inhibition Diametersc
nearest whole mm |
Equivalent MICc (mg/ml) |
Reference |
||||
|---|---|---|---|---|---|---|---|---|
| (µg) | R | I | S | R | I | S | ||
| Ciprofloxacin, 250 mg | Cip, 1 | ≤24 | ≥0.03 | 8 | ||||
| Ciprofloxacin, 500 mg | Cip, 5 | ≤29 | 30-35 | ≥36 | ≥1.0 | 0.13-0.5 | ≤0.06 | 18 |
| Cip, 5 | ≤22 | ≥1.0 | 6 | |||||
| Ofloxacin, 400 mg | Ofx, 5 | ≤24 | 25-30 | ≥31 | ≥2.0 | 0.5-1.0 | ≤0.25 | 18 |
| Ofx, 5 | ≤24 | ≥1.0 | 6 | |||||
| Enoxacin, 400 mg | Enx, 10 | ≤31 | ≥32 | ≥1.0 | 0.5 | ≤0.25 | 18 | |
| Lomefloxacin, 400 mg | Lom, 10 | ≤26 | 27-35 | ≥36 | ≥2.0 | 0.25-1.0 | ≤0.125 | 18 |
| Norfloxacin, 800 mg | Nor, 5 | ≤32 | 33-35 | ≥36 | ≥1.0 | 0.5 | ≤0.25 | 18 |
aThese criteria have not been recommended by the National Committee for Clinical Laboratory Standards (NCCLS); they are provided to guide interpretation of susceptibilities until the NCCLS establishes criteria.
bAbbreviations: MIC, minimal inhibitory concentration (µg/ml); R, resistant; I, intermediate resistance; S, susceptible; Cip, ciprofloxacin; Ofx, ofoxacin; Enx, enoxacin; Lom, lomefloxacin; Nor, norfloxacin.
cWith the exception of norfloxacin, criteria for the susceptible categories are those designated by the NCCLS (16,17); criteria for the interpretation of the susceptible category for norfloxacin were proposed by CDC (18).
