In vitro susceptibility testing for the new ketolide antibacterial telithromycin - influence of methodologic factors

Antimicrobial susceptibility testing of common bacterial pathogens responsible for community-acquired respiratory tract infections is essential for monitoring the prevalence and distribution of drug resistance and for detecting new patterns of resistance at both the global and local levels. However, a number of factors may affect antimicrobial susceptibility testing results (including the test method used, the composition and pH of test media, the size and age of bacterial inocula, and incubation conditions), thus making comparison of data among studies problematic. This review summarizes the impacts of these factors on in vitro susceptibility test results for telithromycin, the first ketolide antibacterial agent approved for clinical use in the treatment of community-acquired respiratory tract infections.