Metronidazole-resistant Helicobacter pylori strains among Saudi patients with dyspepsia

ABSTRACT

To determine how common are metronidazole-resistant [MTZ-R] Helicobacter pylori [H.pylori] strains in Saudi patients. A prospective study in patients with dyspepsia attending for gastroscopy at Asir Central Hospital, Abha, Saudi Arabia. Each biopsy specimen was inoculated on a Skirrow's selective medium and incubated at 37 °C under a microaerophilic atmosphere for 3 to 7 days. Suspected colonies were tested further for identification and susceptibility testing. A total of 40 different H.pylori strains were studied. Of the 40 strains isolated, 16 [40.0%] were MTZ-R. Females showed a higher, though not significant, rate of MTZ-R [47%] than males [33%] [p=0.37]. Furthermore, patients with MTZ-R strains showed lower median age [35 years], compared to those with susceptible ones [45 years]. However, the difference was not significant [t=1.89, p=0.07]. Moreover, MTZ-R was not significantly affected by the type of endoscopic diagnosis [duodenal ulcer [30%] and gastritis [50%], p=0.20]. Since MTZ-R H.pylori strains are frequent [40%], it is recommended to test MTZ susceptibility if possible before treatment, to guide the selection of appropriate therapy and to avoid eradication failure, in particular patients with a history of H.pylori treatment failure. Metronidazole resistance was not affected by age, sex or diagnosis