A NEW SEMISOLID AGAR DILUTION METHOD FOR DETERMINING AMOXICILLIN, CLARITHROMYCIN AND AZITHROMYCIN MICS FOR HELICOBACTER-PYLORI ISOLATES

The MICs of amoxycillin, clarithromycin and azithromycin for 26 strain s of Helicobacter pylori were determined using Mueller-Hinton semi-sol id agar (SSA) without CO2 incubation, as in the conventional agar dilu tion method, The tested H. pylori strains grew satisfactorily in the S SA method within 48 h of incubation, Reasonable values of MICs of thre e antibiotics for these strains were obtained by this method, avoiding the inactivation of macrolides due to acidification of the medium. By this method, the MICs of the antibiotics for the reference strains we re within the acceptable NCCLS ranges for quality control.