TABLE 4.
Trimethoprim susceptibility and trimethoprim resistance factors in SXT-resistant S. pyogenes isolates from Germany
| No. (%) of isolates | |||||
|---|---|---|---|---|---|
| Total | Resistance factor detecteda |
Resistant (MIC > 4 mg/liter) | Intermediate (MIC = 4 mg/liter) | Susceptible (MIC < 4 mg/liter) | |
| dfrG | dfrF | ||||
| 37 (100) | 0 | 4 (10.8) | 5b (13.5) | 12 (32.4) | 20 (54.1) |
a
All isolates tested were negative for the resistance genes dfrA, dfrD, and dfrK.
b
Four out of 5 resistant isolates were positive for the dfrF resistance gene. For one isolate, none of the known resistance factors was detected.