Antimicrobial susceptibility of Helicobacter pylori isolated from gastric biopsies in dyspeptic patients.

The objective of this study was to evaluate the prevalence of antimicrobial resistance in Helicobacter pylori isolated from the antrum and corpus of dyspeptic patients in Khon Kaen, Thailand, and to compare the antimicrobial susceptibility patterns of H. pylori isolated from the antrum and corpus in individual patients. Antimicrobial susceptibility was determined by disk diffusion, studying susceptibility to metronidazole, clarithromycin, amoxicillin, erythromycin, ciprofloxacin, and tetracycline. The H. pylori resistant rate to at least one of the six antimicrobial agents tested was 37%. The resistance rates were 30.2% for metronidazole, 9.2% for ciprofloxacin, 5% for clarithromycin, 2.4% for amoxicillin, and 1.7% for erythromycin and tetracycline. Single, double, and more than double antimicrobial resistances were found in 27.7, 6.7 and 2.5%, respectively. Antimicrobial susceptibility testing revealed 11 antibiotypes. The most common antimicrobial susceptibility pattern found was sensitivity to 6 antimicrobial agents (63%). H. pylori antimicrobial resistance in specimens isolated from the antrum and corpus were nearly equivalent, 37.3% (22/59) and 36.7% (22/60), respectively. Most of the H. pylori specimens isolated from the antrum and corpus in individual patients were identical (87.7%).