[Bacteriological and clinical studies on metronidazole in Bacteroides fragilis infections (author's transl)].

The antimicrobial activity of 24 Bacteroides fragilis, 13 Bacteroides thetaiotaomicron and 5 Bacteroides vulgatus, all of which were recent clinical isolates, was determined by the agar dilution technique. These three species had similar susceptibility patterns, but the B. thetaiotaomicron strains were generally less susceptible than the B. fragilis strains. Clindamycin was very active against 81% of the Bacteroides strains at 3.1 mcg/ml of less while 21% of the Bacteroides strains had MICs of 100 mcg/ml or above. Metronidazole was active against all Bacteroides strains at 1.6 mcg/ml or less. The patients with decubitus ulcers and B. fragilis septicemia, who responded satisfactorily to the combination of metronidazole and tobramycin, were presented.