Skip to main content

Table 1 Resistance rates according to the agar dilution method (ADM) and E-test

From: E-test versus agar dilution for antibiotic susceptibility testing of Helicobacter pylori: a comparison study

AntibioticClinical breakpoint (mg/L)Resistance rate (%) n = 72MIC50a (mg/L)MIC90a (mg/L)Essential agreement (%)Kappa coefficient95% confidence
interval
ADME-testADME-testADME-test   
Amoxicillin> 0.1253/72 (4.2)4/72 (5.6)0.0320.0160.0640.12593.10.25− 0.38 to 0.88
Metronidazole> 830/72 (41.7)33/72 (45.8)88646484.70.690.52 to 0.85
Clarithromycin> 0.53/72 (4.2)5/72 (6.9)0.0320.0320.250.2594.40.47− 0.29 to 0.97
Levofloxacin> 118/72 (25.0)19/71 (26.4)0.250.258893.10.810.66 to 0.97
Tetracycline> 10/72 (0.0)2/71 (2.8)0.1250.0640.50.2597.2
  1. aMIC50/MIC90: minimum inhibitory concentrations that inhibited 50 and 90% of the isolates. For comparability with ADM, the upper limits were set as 1 mg/L for amoxicillin, 2 mg/L for clarithromycin and tetracycline, 8 mg/L for levofloxacin, and 64 mg/L for metronidazole, and the lower limits were set as 0.016 mg/L for amoxicillin, 0.032 mg/L for clarithromycin and tetracycline, 0.125 mg/L for levofloxacin, and 1 mg/L for metronidazole