Open AccessBacteriostatic and Bactericidal Activities of Various Antibiotics Against Bacteroides fragilis
Author(s) -
R.J. Zabransky,
John Johnston,
Kathrin Hauser
Publication year - 1973
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.3.2.152
Subject(s) - bacteroides fragilis , lincomycin , clindamycin , microbiology and biotechnology , tetracycline , antibiotics , penicillin , chloramphenicol , minimum inhibitory concentration , erythromycin , bacteroides , antimicrobial , chemistry , biology , bacteria , genetics
The minimal inhibitory concentrations and minimal bactericidal concentrations of seven antibiotics were determined by broth dilution tests for 50 clinical isolates ofBacteroides fragilis . Chloramphenicol, erythromycin, lincomycin, clindamycin, and rifampin inhibited 80 to 100% of the strains at concentrations attainable in the serum. Penicillin and tetracycline were less effective, inhibiting 4 and 40% of the strains, respectively, at concentrations attainable in the serum. The strains exhibited a bimodal distribution with tetracycline but a very narrow pattern of susceptibility with chloramphenicol. Bactericidal concentrations were 4- to 128- fold higher than minimal inhibitory concentrations for all antibiotics; only clindamycin showed bactericidal activity at levels attainable in serum. Clindamycin was significantly more effective than lincomycin as determined by tests of inhibitory and bactericidal activity. The distinct patterns of susceptibility ofB. fragilis may be used for the preliminary selection of antimicrobial therapy.