TABLE 1.
In vitro antimicrobial activities of ceftriaxone, azithromycin, or their combination against S. pneumoniae strains 741 and ATCC 49619
| Strain | MIC (μg/ml) |
FICIa | ||
|---|---|---|---|---|
| Ceftriaxone | Azithromycin | Ceftriaxone-azithromycin combination (ceftriaxone MIC/azithromycin MIC) | ||
| 741 | 0.5 | 2 | 0.25/1 | 1 |
| ATCC 49619b | 0.062 | 0.125 | 0.015/0.062 | 0.75 |
a
The results were interpreted as follows: FICI ≤ 0.5, synergy; 0.5 < FICI ≤ 4, no interaction; and FICI > 4, antagonism.
b
S. pneumoniae strain ATCC 49619 was used as a quality control strain.