EFFECT OF INOCULUM, PH, AND MEDIUM ON THE ACTIVITY OF CIPROFLOXACIN AGAINST ANAEROBIC-BACTERIA

The in vitro activity of ciprofloxacin against 30 Bacteroides fragilis group, 30 Clostridium and 30 Peptococcaceae strains was determined by the agar dilution method in 2 culture media at 3 pH and in 3 inoculum densities. In Wilkins-Chalgren agar the MIC [minimum inhibitory concentrations] for 90% of the strains were 0.12 .mu.g/ml for B. fragilis, 0.5 .mu.g/ml for Clostridium spp. and 2 .mu.g/ml for Peptococcaceae. The pH and medium composition affected the MIC of ciprofloxacin.