TABLE 1.
Sensitivities of 20 H. pylori isolates to penicillins, determined by the disk diffusion method
| Resistance level | Amoxicillin MIC (μg/ml)a | Mean zone of inhibition (mm)b
|
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Amp | Pen | Oxa | Ticar | Mez | Naf | Pip | Amox-Clav | ||
| Sensitive | 0.016 | 27.1 | 23.8 | 6.4 | 39 | 38.5 | 6.4 | 39.4 | 42.8 |
| Low | 2 | 20.8 | 19 | 6.4 | 35.2 | 31.5 | 7.6 | 31.1 | 34.9 |
| High | >32 | 19.4 | 18.3 | 6.4 | 27 | 26.5 | 6.4 | 25.7 | 29.2 |
a
Determined by agar dilution.
b
A value of 6.4 mm is the size of the disk; i.e., there is no zone of inhibition. Amp, ampicillin; Pen, penicillin; Oxa, oxacillin; Ticar, ticarcillin; Mez, mezlocillin; Naf, nafcillin; Pip, piperacillin; Amox-Clav, amoxicillin-clavulanic acid.