Abstract
The authors determined the susceptibility of 55 single clinical strains of Helicobacter pylori isolated in the Montreal area to 10 antibiotics by three different methods - an agar dilution technique considered to be the gold standard, a disk diffusion method and the E-test. Testing was performed on Mueller-Hinton agar supplemented with 10% sheep blood; plates were incubated at 37°C for 72 h in a microaerophilic atmosphere. The metronidazole resistance rate is about 11% in the Montreal area. Macrolides are very active against H pylori isolates, with few variations in activity between older and newer molecules. Correlation among different methods was not as good as reported in the literature for metronidazole.