Evaluation of Four Methods for Antimicrobial Susceptibility Testing of Helicobacter pylori in Routine Practice.
- Author:
Jung Oak KANG
1
;
Dongsoo HAN
;
Tae Yeal CHOI
Author Information
1. Department of Laboratory Medicine, College of Medicine, Hanyang University, Seoul, Korea. jokang@hanyang.ac.kr
- Publication Type:Original Article
- Keywords:
Helicobacter pylori;
Antimicrobial susceptibility test;
Modified broth microdilution;
E test;
Disk diffusion;
Amoxicillin;
Clarithromycin;
Metronidazole
- MeSH:
Agar;
Amoxicillin;
Clarithromycin;
Diffusion;
Egg Yolk;
Helicobacter pylori*;
Helicobacter*;
Metronidazole
- From:Korean Journal of Clinical Microbiology
2005;8(1):82-89
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: We compared currently available four antimicrobial susceptibility test methods for H.pylori to find out a practical method suitable for testing a few strains of H.pylori at a time in the clinical microbiology laboratory. METHODS: With 37 clinical isolates of H.pylori, antimicrobial susceptibility tests were performed against amoxicillin (AMX), clarithromycin (CLR), and metronidazole (MTZ) using disk diffusion method with egg yolk emulsion (EYE) media, E test with EYE and Mueller Hinton blood agar plate (MH BAP), and modified broth microdilution methods (mBMD). RESULTS: The results of AMX and CLR showed a complete agreement between the four methods. For MTZ, however, a significant discrepancy was observed between the results obtained by the four methods. In four strains exhibiting high minimal inhibitory concentrations (MIC, > or =32 mg/L) to MTZ, category agreement was excellent, but correlation was not good in 13 strains with the MTZ MICs of 8 to 16 mg/L. In 20 strains with MTZ MICs between 0.25 mg/L and 4 mg/L, category agreement was excellent, but correlation between MICs or inhibitory zone diameters was not good. Etest EYE and Etest MH BAP methods showed a 100% agreement in the susceptibility category of MTZ. CONCLUSION: In routine practice, the most practical method for testing susceptibility of H.pylori to AMX and CLR seems to be the disk diffusion method with EYE or MH BAP. But for MTZ, a duplicate test using both Etest and disk diffusion test is recommended until more standardized, economical, and technically easier test methods become available.
