TABLE 5.
MIC50, MIC90, and prevalence of resistance for H. influenzae (n = 2,645)
| Antibiotic | MIC50 (μg/ml) | MIC90 (μg/ml) | Susceptibility (%)
|
PK/PDa breakpoints (μg/ml) | |
|---|---|---|---|---|---|
| NCCLS | PK/PD | ||||
| Ampicillin | ≤0.25 | ≥32 | 74.9 | 76.0 | ≤2 |
| Amoxicillin-clavulanate | 0.5 | 2 | 99.9 | 96.0 (99.9)b | ≤2 (≤4)b |
| Cefaclor | 4 | ≥16 | 82.1 | 1.4 | ≤0.5 |
| Cefuroxime-axetil | 1 | 2 | 100 | 72.8 | ≤1 |
| Azithromycin | 1 | 2 | 100 | 2.2 | ≤0.12 |
| Clarithromycin | 8 | 16 | 72.3 | 1.2 | ≤0.25 |
| Ciprofloxacin | ≤0.5 | ≤0.5 | 100 | 100 | ≤1 |
a
PK/PD, pharmacokinetic/pharmacodynamic.
b
In parentheses are percentage of susceptibility and the breakpoint for the sustained-release 2,000/125-mg amoxicillin/clavulanate formulation.