Comparison of the E test and agar dilution method for antimicrobial suceptibility testing of Helicobacter pylori

Eur J Clin Microbiol Infect Dis. 2002 Jul;21(7):549-52. doi: 10.1007/s10096-002-0757-6. Epub 2002 Jun 28.


A multicentre study was carried out in order to validate the E test in comparison with the reference agar dilution method for testing the susceptibility of Helicobacter pylori to amoxicillin, clarithromycin, and metronidazole. Ten clinical isolates and one control collection isolate ( Helicobacter pylori ATCC 43504) were tested blindly at four centres according to a uniform methodology. The E test showed excellent intra- and inter-laboratory correlations with the agar dilution method for amoxicillin and clarithromycin (>98% agreement within 2 log(2) dilution steps). For metronidazole, however, the E test revealed significantly higher minimum inhibitory concentration values (>2 log(2)) against 5 of the 10 Helicobacter pylori strains tested. Overall, neither method was found reliable for testing the susceptibility of Helicobacter pylori to metronidazole, since both tended to lack reproducibility.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amoxicillin / pharmacology
  • Anti-Bacterial Agents / pharmacology*
  • Clarithromycin / pharmacology
  • Drug Resistance, Bacterial*
  • Helicobacter Infections / microbiology
  • Helicobacter pylori / classification
  • Helicobacter pylori / drug effects*
  • Helicobacter pylori / isolation & purification
  • Helicobacter pylori / physiology
  • Humans
  • Metronidazole / pharmacology
  • Microbial Sensitivity Tests / methods*
  • Reproducibility of Results


  • Anti-Bacterial Agents
  • Metronidazole
  • Amoxicillin
  • Clarithromycin