[Antimicrobial activities of clarithromycin against clinical isolates].

To examine the antimicrobial activity of clarithromycin (CAM) against strains clinically isolated from outpatients in 1994, minimum inhibitory concentrations (MICs) were determined for CAM and the control drugs. The results were as follows; 1. MIC50 and MIC90 of CAM were similar to those investigated in 1980's against many bacterial species. 2. CAM showed strong antimicrobial activities against beta-lactamase producing Moraxella subgenus Branhamella catarrhalis, Bordetella pertussis, Campylobacter jejuni subsp. jejuni and Peptostreptococcus spp. 3. It appears that resistance to MLs including CAM is increasing among Streptococcus pneumoniae.