Affiliation:
1. Department of Medical Microbiology, St. Thomas's Hospital Medical School, London SE1 7EH, England
Abstract
Minimum inhibitory concentrations (MICs) of sulfamethoxazole (SMX) and trimethoprim (TMP), alone and in three combinations, 20:1, 1:1, and 1:20, were determined on Diagnostic Sensitivity Test (DST) and Mueller-Hinton (MH) agars containing lysed blood for various inocula of 91 strains of
Bacteroides fragilis
from the U.S.A. and U.K. MICs of SMX were high with large inocula and higher on MH than DST, but results for TMP were less affected by these two factors. True SMX resistance was rare: 10 U.S.A. strains previously reported as resistant appeared to be susceptible. Maximum potentiation of MICs was observed when SMX and TMP were combined in ratios close to those of the ratios of their MICs, that is, SMX/TMP 20:1 for large inocula and the reverse for small inocula for determinations on DST and usually 20:1 for all inoculum sizes on MH. These observations explain some of the discrepancies in reports, but defer the problem of potential usefulness of the drugs in the treatment of infection with anaerobes to future study.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Pharmacology (medical),Pharmacology
Reference6 articles.
1. Antagonists of nucleic acid derivatives;Elion G. B.;J. Biol. Chem.,1954
2. Phillips I. 1974. Antibiotic sensitivity of non-sporing anaerobes p. 37-57. In I. Phillips and M. Sussman (ed.) Infection with non-sporing anaerobic bacteria. Churchill Livingstone Edinburgh and London.
3. Susceptibility ofBacteroides fragilis to trimethoprim and sulphamethoxazole;Phillips I.;Lancet,1974
4. Lack of activity of sulfamethoxazole and trimethoprim against anaerobic bacteria;Rosenblatt J. E.;Antimicrob. Agents Chemother.,1974
5. Sutter V. L. and J. A. Washington II. 1974. Susceptibility testing of anaerobes p. 436-438. In E. H. Lennette E. H. Spaulding and J. P. Truant (ed.) Manual of clinical microbiology 2nd ed. American Society for Microbiology Washington D.C.
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