Comparative analysis of disk diffusion and liquid medium microdillution methods for testing the antibiotic susceptibility patterns of anaerobic bacterial strains isolated from intra-abdominal infections

Abstract

The antibiotic resistance aspects concerning the bacterial strains isolated from intra-abdominal infections signify at present a major problem of therapy. The empiric pre-operatory antimicrobial therapy plays a key role in the management and course of the intra-abdominal infections, an inappropriate therapy resulting in a poor outcome of the clinical cases and an increase of bacterial resistance. The purpose of the present paper was to compare the results of the antibiotic susceptibility of some selected anaerobic strains to certain antibiotics used in the empiric therapy of intra-abdominal infections, achieved by two different methods, in order to select for the current practice the most reliable, simple and rapid one. We have found a good correlation between the results obtained by the standard, Brucella broth microdilution method recommended by CLSI and the disk diffusion method (recommended by Bailey and Scott, 2002), for all tested antibiotics, demonstrating the possibility to use this last simplified method as an alternative to the laborious and time-consuming dilution method, for the routine testing of the antibiotic susceptibility of anaerobic stranis isolated in severe infections.