Abstract
A medium, Bacteroides fragilis bile-esculin (BBE) agar, was designed for the selection and, presumptive identification of the B. fragilis group. BBE agar contains bile, esculin, ferric ammonium citrate, hemin, and gentamicin in a Trypticase soy agar base. Growth in the presence of 20% bile and esculin hydrolysis, detected by blackening of the medium, provide presumptive evidence for the identification of the B. fragilis group. In addition to stimulating the growth of many strains of the B. fragilis group, hemin provides the option of testing isolates for catalase production. Gentamicin and bile prevent the growth of most organisms other than the esculin-positive bacteroides that can tolerate bile. Of 160 clinical isolates of the B. fragilis group tested on BBE agar, 159 grew well on the medium and 157 blackened it. Other anaerobes, Enterobacteriaceae, and enterococci either failed to grow on BBE agar or did not produce the characteristic morphology and blackening associated with isolates of the B. fragilis group. In a clinical laboratory trial, 687 specimens from patients were inoculated onto BBE agar plates. The B. fragilis group was recovered from 81 (11.8%) of these specimens in 24 to 48 h. Use of BBE agar in the clinical laboratory enables earlier recovery and identification of this important pathogen.
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- Casemore D. P. Gentamicin as a bactericidal agent in virological tissue cultures. J Clin Pathol. 1967 May;20(3):298–299. doi: 10.1136/jcp.20.3.298. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Draper D. L., Barry A. L. Rapid identification of Bacteroides fragilis with bile and antibiotic disks. J Clin Microbiol. 1977 Apr;5(4):439–443. doi: 10.1128/jcm.5.4.439-443.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Goodnow R. A., Lehr C. D., Shade F. J., Wisecarver J. L. Mouse potency assay for Bordetella bronchiseptica bacterins. J Clin Microbiol. 1977 Oct;6(4):337–339. doi: 10.1128/jcm.6.4.337-339.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gorbach S. L., Bartlett J. G. Anaerobic infections (second of three parts). N Engl J Med. 1974 May 30;290(22):1237–1245. doi: 10.1056/NEJM197405302902207. [DOI] [PubMed] [Google Scholar]
- Gorbach S. L., Bartlett J. G. Anaerobic infections (third of three parts). N Engl J Med. 1974 Jun 6;290(23):1289–1294. doi: 10.1056/NEJM197406062902305. [DOI] [PubMed] [Google Scholar]
- Gorbach S. L., Bartlett J. G. Anaerobic infections. 1. N Engl J Med. 1974 May 23;290(21):1177–1184. doi: 10.1056/NEJM197405232902106. [DOI] [PubMed] [Google Scholar]
- Hackman A. S., Wilkins T. D. In vivo protection of Fusobacterium necrophorum from penicillin by Bacteroides fragilis. Antimicrob Agents Chemother. 1975 May;7(5):698–703. doi: 10.1128/aac.7.5.698. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Salyers A. A., Wong J., Wilkins T. D. Beta-Lactamase activity in strains of Bacteroides melaninogenicus and Bacteroides oralis. Antimicrob Agents Chemother. 1977 Jan;11(1):142–146. doi: 10.1128/aac.11.1.142. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Shimada K., Sutter V. L., Finegold S. M. Effect of bile and desoxycholate on gram-negative anaerobic bacteria. Appl Microbiol. 1970 Nov;20(5):737–741. doi: 10.1128/am.20.5.737-741.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sutter V. L., Finegold S. M. Antibiotic disc susceptibility tests for rapid presumptive identification of Gram-negative anaerobic bacilli. Appl Microbiol. 1971 Jan;21(1):13–20. doi: 10.1128/am.21.1.13-20.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vargo V., Korzeniowski M., Spaulding E. H. Tryptic soy bile-kanamycin test for the indentification of Bacteroides fragilis. Appl Microbiol. 1974 Mar;27(3):480–483. doi: 10.1128/am.27.3.480-483.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wilkins T. D., Chalgren S. L., Jimenez-Ulate F., Drake C. R., Jr, Johnson J. L. Inhibition of Bacteroides fragilis on blood agar plates and reversal of inhibition by added hemin. J Clin Microbiol. 1976 Mar;3(3):359–363. doi: 10.1128/jcm.3.3.359-363.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]