Affiliation:
1. Division of Infectious Diseases, Department of Medicine, The Ohio State University College of Medicine, Columbus, Ohio 43210
Abstract
A microdilution technique using commercially available media and materials was developed and used to determine the minimal inhibitory concentrations (MICs) of clindamycin, chloramphenicol, tetracycline, minocycline, ampicillin, carbenicillin, cephalothin, and gentamicin for 101 anaerobic isolates. Representative strains of
Bacteroides, Clostridium, Fusobacterium, Peptococcus
, and
Peptostreptococcus
were tested. The use of Schaedler broth at pH 7.2, an inoculum of 10
5
to 10
7
colony-forming units per ml, and incubation at 35 C in an anaerobic glove box with an atmosphere of 80% nitrogen, 10% hydrogen, and 10% carbon dioxide resulted in good growth and easily interpretable results. After 48 h of incubation, 97% of strains tested were inhibited by 3.1 μg or less of clindamycin per ml and 98% were inhibited by 12.5 μg or less of chloramphenicol per ml. Tetracycline and minocycline inhibited 81 and 88% of strains tested in concentrations of 1.6 μg or less per ml and 1.6 μg or less per ml, respectively. Ampicillin inhibited all strains other than
B. fragilis
in concentrations of 3.1 μg or less per ml. Excluding certain strains of
Bacteroides
and
Clostridium
, carbenicillin in concentrations of 12.5 μg or less per ml and cephalothin in concentrations of 6.2 μg or less per ml inhibited all strains tested. Gentamicin was inactive although some strains of anaerobic cocci and
Bacteroides
were inhibited by 3.1 μg or less per ml. After 18 to 24 h of incubation, eight of the 101 strains had not grown sufficiently for MICs to be determined; for the 93 strains which had grown sufficiently, 93% of 744 MICs were the same or one concentration lower than the 48-h MICs.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Pharmacology (medical),Pharmacology
Cited by
72 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献