Identification of the Prevalence of Resistance to Clarithromycin in Helicobacter Pylori Isolated from Gastric Biopsy via PCR Method

Helicobacter pylori infection is the most common worldwide human infection, affecting approximately half of the world’s population. One of the most important causes of failure in the treatment of helicobacter pylori infection is its resistance to antibiotics. The purpose of this study was to evaluate the antibiotic resistance of helicobacter pylori, isolated from patients, referring to Shahid Beheshti Hospital of Shiraz, Iran. In this cross-sectional study, biopsy samples were obtained from 80 patients, referring to the endoscopy department of Shahid Beheshti Hospital of Shiraz. Biopsy samples were transferred to the laboratory in thioglycollate broth. After conducting biochemical tests for final confirmation, PCR tests were performed. In order to perform an antibiotic resistance test, Clinical and Laboratory Standards Institute (CLSI) method was applied. Out of 80 cases, 59 samples (73.75%) were infected with helicobacter pylori. Among these cases, 36 samples (61%) were resistant to metronidazole, 19 samples (32.2%) were resistant to amoxicillin, and 14 samples (23.72%) were resistant to tetracycline. As the results indicated, resistance to clarithromycin was the lowest, reported in two cases (3.35%). Considering the high resistance of samples to metronidazole, it is necessary to replace this antibiotic with clarithromycin or other antibiotics in therapeutic regimens.