TABLE 2.
MICs of clarithromycin and azithromycin for M. massiliense and M. bolletii clinical and reference strains devoid of rrl mutations, with regard to the method of susceptibility testing and the time of incubation
| Species (n)a | Antibiotic | Testing method | Incubation time (days)b | MIC50 (μg/ml) | MIC90 (μg/ml) | MIC range (μg/ml) |
|---|---|---|---|---|---|---|
| M. massiliense (26) | Clarithromycin | Etest | 5 | 0.125 | 0.5 | 0.016-0.5 |
| 7 | 0.125 | 0.5 | 0.016-0.5 | |||
| Microdilution | 5 | 0.12 | 0.5 | <0.12-0.5 | ||
| 7 | 0.25 | 0.5 | <0.12-2 | |||
| 9 | 0.25 | 1 | <0.12-2 | |||
| 14 | 0.5 | 1 | <0.12-2 | |||
| Azithromycin | Etest | 5 | 0.38 | 2 | 0.047-3 | |
| 7 | 1 | 2 | 1-2 | |||
| M. bolletii (14) | Clarithromycin | Etest | 5 | 16 | 48 | 0.25->256 |
| 7 | >256 | >256 | 1->256 | |||
| Microdilution | 5 | 2 | 16 | 0.25-16 | ||
| 7 | 4 | 16 | 0.5-16 | |||
| 9 | >16 | >16 | 4->16 | |||
| 14 | >16 | >16 | >16->16 | |||
| Azithromycin | Etest | 5 | 6 | 256 | 4->256 | |
| 7 | 12 | >256 | 4->256 |
a
n, number of strains.
b
Day of testing.