Resistance rate to antibiotics of Helicobacter pylori isolates in eastern Taiwan

Background and Aim: Prevalence of Helicobacter pylori (H. pylori) strains resistant to metronidazole, clarithromycin and amoxicillin is increasing worldwide. The aim of this study was to determine the antibiotic susceptibility patterns in H. pylori strains isolated from eastern Taiwan. Methods: One strain each of H. pylori was isolated from 133 symptomatic patients and subjected to determination of the minimal inhibitory concentration (MIC) by the Epsilometer test (E-test) for four antibiotics commonly used in the treatment of H. pylori infections. Results: None of the strains were resistant to tetracycline. Resistance to metronidazole (8 mu g/mL), clarithromycin (1 mu g/mL) and amoxicillin (8 mu g/mL) was found in 51.9%, 13.5% and 36.1% of the isolates, respectively. Metronidazole-resistant strains were isolated more frequently from women (49/78; 62.8%) than from men (20/55; 36.4%). Resistance to at least two antimicrobial agents was detected in 33.8% of the isolates. There was a high rate of resistance to both metronidazole and amoxicillin (18.1%). Conclusions: Clarithromycin and tetracycline may provide useful components of treatment regimens in eastern Taiwan. In addition, pretreatment microbial susceptibility testing rather than empiric therapy is highly recommended for eradication of H. pylori infection.