TABLE 1.
Geometric mean MICs of four antibiotics for 12 strains of H. influenzae tested under standard conditions compared to MICs with a single deviation from MICs obtained under standard conditions
| Antimicrobial agent | Geometric mean MIC (μg/ml) under the following conditions:
|
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Standarda | LHB medium | Atmosphere 5–7% CO2 | Inoculum
|
Incubation time
|
Age of colony used for inoculum
|
||||||
| 5 × 106 CFU/ml | 5 × 104 CFU/ml | 16 h | 24 h | 8 h | 12 h | 20 h | 24 h | ||||
| Telithromycin | 2.00 | 1.68 | 3.78 | 2.12 | 1.50 | 2.00 | 2.12 | 2.00 | 2.25 | 2.38 | 2.00 |
| Clarithromycin | 7.55 | 5.99 | 12.7 | 9.51 | 5.66 | 7.55 | 8.48 | 8.48 | 8.98 | 8.98 | 8.98 |
| Azithromycin | 0.94 | 0.75 | 3.00 | 1.12 | 0.89 | 0.89 | 1.19 | 1.19 | 1.26 | 1.26 | 1.19 |
| Ampicillin | 1.50 | 1.33 | 1.33 | 2.45 | 1.19 | 1.50 | 1.41 | 1.59 | 1.41 | 1.19 | 1.41 |
a
Sixteen-hour colonies suspended in saline and adjusted to yield an inoculum with ca. 5 × 105 CFU/ml in HTM broth, incubated for 20 h in ambient air.