Antimicrobial Resistances of Helicobacter pylori in Korean Patients with Duodenal Ulcer

Han, Dong Soo; Cho, Yun Ju; Son, Joo Hyun; Park, Kyung Nam; Kang, Jung Ok

Abstract

BACKGROUND/AIMS: Clarithromycin and metronidazole are most frequently used antibiotics for eradication of H. pylori infection. Primary resistance to metronidazole is high in some populations. Success of H. pylori eradication therapy may be limited by antibiotic resistance. In this study we evaluate primary resistance of clarithromycin and metronidazole in Korean duodenal ulIcer patients.
METHODS
H. pylori isolated from gastric biopsies of patients with newly diagnosed duodenal ulcer were cultured in egg yolk emulsion agar, brain heart infusion broth and tested for clarithromycin and metronidazole resistance by microdilution broth, E test(AB Biodisk, Solna, Sweden) and disk diffusion methods. The breakpoint MIC for Spg/mL in metronidazole, 2pg/mL and 12mm in clarithromycin. The patients with previous trip]e therapy were excluded.
RESULTS
One of 40(2%) isolates was resistant to clarithromycin in microdilution broth, E test, and disk diffusion methods. Metronidazole resistance were 22/40(55%) in microdilution rnethod(9/22 had MICs w 32pg/mL), 26 of 40(65%) in E test(19/26 had MICs >32pg/mL), 25 of 40(62.5%) in disk diffusion methods. Age, sex and smoking did not influence on the results.
CONCLUSIONS
Metronidazole resistance is high(55%) in Korea, but clarithromycin resistance is relatively low, therefore proper antimicrobial treatrnent should be considered in regard to antibiotic susceptibility test to H. pylori.