Abstract
To determine patterns of antimicrobial susceptibility among enterococci and to assess molecular characteristics of vancomycin-resistant enterococci, 157 clinical blood isolates of enterococci from 10 hospitals in Cincinnati, Ohio, were prospectively collected during a 6-month period from February to July 1995. The isolates included 108 (69%) E. faecalis isolates, 46 (29%) E. faecium isolates, and 1 isolate each of E. avium, E. durans, and E. gallinarum. The E. faecalis and E. faecium isolates differed in their susceptibilities to ampicillin (100 versus 20%), ampicillin-sulbactam (100 versus 13%), vancomycin (100 versus 57%), imipenem (94 versus 2%), and high levels of gentamicin (59 versus 83%). Supplemental susceptibility testing of the 21 vancomycin-resistant isolates showed that 21 (100%) were susceptible to chloramphenicol and that only 7 (33%) were susceptible to doxycycline. Nineteen (90%) of the vancomycin-resistant E. faecium isolates were of the VanB phenotype, with vanB resistance genes detected by PCR and hybridization with gene-specific probes; and the E. gallinarum isolates demonstrated the VanC phenotype with the vanC1 gene. One vancomycin-resistant E. faecium isolate was highly resistant to both teicoplanin and vancomycin, corresponding to the VanA phenotype; however, it was found to have the vanB gene. Pulsed-field gel electrophoresis (PFGE) revealed that all of the 19 E. faecium isolates with the VanB phenotype had identical to closely related banding patterns. Hybridization of restriction enzyme-digested DNA separated by PFGE with a vanB gene probe demonstrated differences in the locations of vanB genes that corresponded closely to the PFGE banding patterns. Our study has documented that the emerging vancomycin resistance in our city was mainly due to the clonal dissemination of a single strain of E. faecium VanB.
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Selected References
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- Arthur M., Courvalin P. Genetics and mechanisms of glycopeptide resistance in enterococci. Antimicrob Agents Chemother. 1993 Aug;37(8):1563–1571. doi: 10.1128/aac.37.8.1563. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Buschelman B. J., Bale M. J., Jones R. N. Species identification and determination of high-level aminoglycoside resistance among enterococci. Comparison study of sterile body fluid isolates, 1985-1991. Diagn Microbiol Infect Dis. 1993 Feb;16(2):119–122. doi: 10.1016/0732-8893(93)90005-r. [DOI] [PubMed] [Google Scholar]
- Cartwright C. P., Stock F., Fahle G. A., Gill V. J. Comparison of pigment production and motility tests with PCR for reliable identification of intrinsically vancomycin-resistant enterococci. J Clin Microbiol. 1995 Jul;33(7):1931–1933. doi: 10.1128/jcm.33.7.1931-1933.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dutka-Malen S., Evers S., Courvalin P. Detection of glycopeptide resistance genotypes and identification to the species level of clinically relevant enterococci by PCR. J Clin Microbiol. 1995 Jan;33(1):24–27. doi: 10.1128/jcm.33.1.24-27.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Edwards J. R. Meropenem: a microbiological overview. J Antimicrob Chemother. 1995 Jul;36 (Suppl A):1–17. doi: 10.1093/jac/36.suppl_a.1. [DOI] [PubMed] [Google Scholar]
- Frieden T. R., Munsiff S. S., Low D. E., Willey B. M., Williams G., Faur Y., Eisner W., Warren S., Kreiswirth B. Emergence of vancomycin-resistant enterococci in New York City. Lancet. 1993 Jul 10;342(8863):76–79. doi: 10.1016/0140-6736(93)91285-t. [DOI] [PubMed] [Google Scholar]
- Gordon S., Swenson J. M., Hill B. C., Pigott N. E., Facklam R. R., Cooksey R. C., Thornsberry C., Jarvis W. R., Tenover F. C. Antimicrobial susceptibility patterns of common and unusual species of enterococci causing infections in the United States. Enterococcal Study Group. J Clin Microbiol. 1992 Sep;30(9):2373–2378. doi: 10.1128/jcm.30.9.2373-2378.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gutmann L., Billot-Klein D., al-Obeid S., Klare I., Francoual S., Collatz E., van Heijenoort J. Inducible carboxypeptidase activity in vancomycin-resistant enterococci. Antimicrob Agents Chemother. 1992 Jan;36(1):77–80. doi: 10.1128/aac.36.1.77. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hayden M. K., Trenholme G. M., Schultz J. E., Sahm D. F. In vivo development of teicoplanin resistance in a VanB Enterococcus faecium isolate. J Infect Dis. 1993 May;167(5):1224–1227. doi: 10.1093/infdis/167.5.1224. [DOI] [PubMed] [Google Scholar]
- Huang M. B., Baker C. N., Banerjee S., Tenover F. C. Accuracy of the E test for determining antimicrobial susceptibilities of staphylococci, enterococci, Campylobacter jejuni, and gram-negative bacteria resistant to antimicrobial agents. J Clin Microbiol. 1992 Dec;30(12):3243–3248. doi: 10.1128/jcm.30.12.3243-3248.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Miele A., Bandera M., Goldstein B. P. Use of primers selective for vancomycin resistance genes to determine van genotype in enterococci and to study gene organization in VanA isolates. Antimicrob Agents Chemother. 1995 Aug;39(8):1772–1778. doi: 10.1128/aac.39.8.1772. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Miranda A. G., Singh K. V., Murray B. E. DNA fingerprinting of Enterococcus faecium by pulsed-field gel electrophoresis may be a useful epidemiologic tool. J Clin Microbiol. 1991 Dec;29(12):2752–2757. doi: 10.1128/jcm.29.12.2752-2757.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Moreno F., Grota P., Crisp C., Magnon K., Melcher G. P., Jorgensen J. H., Patterson J. E. Clinical and molecular epidemiology of vancomycin-resistant Enterococcus faecium during its emergence in a city in southern Texas. Clin Infect Dis. 1995 Nov;21(5):1234–1237. doi: 10.1093/clinids/21.5.1234. [DOI] [PubMed] [Google Scholar]
- Morris J. G., Jr, Shay D. K., Hebden J. N., McCarter R. J., Jr, Perdue B. E., Jarvis W., Johnson J. A., Dowling T. C., Polish L. B., Schwalbe R. S. Enterococci resistant to multiple antimicrobial agents, including vancomycin. Establishment of endemicity in a university medical center. Ann Intern Med. 1995 Aug 15;123(4):250–259. doi: 10.7326/0003-4819-123-4-199508150-00002. [DOI] [PubMed] [Google Scholar]
- Murray B. E. The life and times of the Enterococcus. Clin Microbiol Rev. 1990 Jan;3(1):46–65. doi: 10.1128/cmr.3.1.46. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ngui-Yen J. H., Bryce E. A., Porter C., Smith J. A. Evaluation of the E test by using selected gram-positive bacteria. J Clin Microbiol. 1992 Aug;30(8):2150–2152. doi: 10.1128/jcm.30.8.2150-2152.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ruoff K. L., de la Maza L., Murtagh M. J., Spargo J. D., Ferraro M. J. Species identities of enterococci isolated from clinical specimens. J Clin Microbiol. 1990 Mar;28(3):435–437. doi: 10.1128/jcm.28.3.435-437.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sader H. S., Pfaller M. A., Tenover F. C., Hollis R. J., Jones R. N. Evaluation and characterization of multiresistant Enterococcus faecium from 12 U.S. medical centers. J Clin Microbiol. 1994 Nov;32(11):2840–2842. doi: 10.1128/jcm.32.11.2840-2842.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schaberg D. R., Culver D. H., Gaynes R. P. Major trends in the microbial etiology of nosocomial infection. Am J Med. 1991 Sep 16;91(3B):72S–75S. doi: 10.1016/0002-9343(91)90346-y. [DOI] [PubMed] [Google Scholar]
- Shlaes D. M., Bouvet A., Devine C., Shlaes J. H., al-Obeid S., Williamson R. Inducible, transferable resistance to vancomycin in Enterococcus faecalis A256. Antimicrob Agents Chemother. 1989 Feb;33(2):198–203. doi: 10.1128/aac.33.2.198. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tenover F. C., Arbeit R. D., Goering R. V., Mickelsen P. A., Murray B. E., Persing D. H., Swaminathan B. Interpreting chromosomal DNA restriction patterns produced by pulsed-field gel electrophoresis: criteria for bacterial strain typing. J Clin Microbiol. 1995 Sep;33(9):2233–2239. doi: 10.1128/jcm.33.9.2233-2239.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- al-Obeid S., Collatz E., Gutmann L. Mechanism of resistance to vancomycin in Enterococcus faecium D366 and Enterococcus faecalis A256. Antimicrob Agents Chemother. 1990 Feb;34(2):252–256. doi: 10.1128/aac.34.2.252. [DOI] [PMC free article] [PubMed] [Google Scholar]