[Multicenter study of the activity of pefloxacin on bacteria isolated in a hospital milieu].

Minimal inhibitory concentrations (MICs) of pefloxacin were evaluated by agar dilution for 3422 bacterial strains isolated in nine hospitals. Enterobacteriaceae proved very sensitive to pefloxacin: 62 p. 100 of 1743 strains tested had MIC less than or equal to 0.12 and 90 p. 100 less than or equal to 1 microgram/ml; but the percent of strains with MIC greater than or equal to 2 varied among the different groups of Enterobacteriaceae: 2.7 p. 100 for E. coli to 39 p. 100 for Serratia. 55 p. 100 for Pseudomonas and 81 p. 100 of Acinetobacter were inhibited by 1 micrograms/ml or less (mode MIC 1 and 0.5 micrograms/ml). Haemophilus sp.: 0.03 and 0.06 micrograms/ml and Gonococci were very sensitive to pefloxacin. The spectrum of pefloxacin extended to Gram positive cocci: MIC of Staphylococci were 0.06 to 8 micrograms/ml (mode MIC: 0.5); Enterococci, other Streptococci and Pneumococci were less sensitive: 2 and 4 micrograms/ml for the majority of strains. Concerning anaerobic bacteria, pefloxacin was more active against Clostridium (0.5 to 1 microgram/ml generally), than against Bacteroides (4 to 16 micrograms/ml).