COMPARISON OF ACTIVITY OF 10 ANTIBIOTICS AGAINST CLINICAL STRAINS OF HELICOBACTER-PYLORI BY 3 DIFFERENT TECHNIQUES

The authors determined the susceptibility of 55 single clinical strain s of Helicobacter pylori isolated in the Montreal area to 10 antibioti cs by three different methods - an agar dilution technique considered to be the gold standard, a disk diffusion method and the E-test. Testi ng was performed on Mueller-Hinton agar supplemented with 10% sheep bl ood; plates were incubated at 37 degrees C for 72 h in a microaerophil ic atmosphere. The metronidazole resistance rate is about 11% in the M ontreal area. Macrolides are very active against H. pylori isolates, w ith few variations in activity between older and newer molecules. Corr elation among different methods was not as good as reported in the lit erature for metronidazole.