Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-30T23:57:13.676Z Has data issue: false hasContentIssue false

Molecular Epidemiology of Vancomycin-Resistant Enterococci: A 2-Year Perspective

Published online by Cambridge University Press:  02 January 2015

Valentina Stosor*
Affiliation:
Division of Clinical Microbiology, Department of Pathology, Northwestern University Medical School, Northwestern Memorial Hospital, Chicago, Illinois Division of Infection Diseases, Department of Medicine, Northwestern University Medical School, Northwestern Memorial Hospital, Chicago, Illinois
Julie Kruszynski
Affiliation:
Clinical Microbiology Laboratory, Northwestern Memorial Hospital, Chicago, Illinois
Terra Suriano
Affiliation:
Infection Control Department, Northwestern Memorial Hospital, Chicago, Illinois NMH Infection Control and Prevention Project, Northwestern Memorial Hospital, Chicago, Illinois
Gary A. Noskin
Affiliation:
Division of Clinical Microbiology, Department of Pathology, Northwestern University Medical School, Northwestern Memorial Hospital, Chicago, Illinois Division of Infection Diseases, Department of Medicine, Northwestern University Medical School, Northwestern Memorial Hospital, Chicago, Illinois Infection Control Department, Northwestern Memorial Hospital, Chicago, Illinois NMH Infection Control and Prevention Project, Northwestern Memorial Hospital, Chicago, Illinois
Lance R. Peterson
Affiliation:
Division of Clinical Microbiology, Department of Pathology, Northwestern University Medical School, Northwestern Memorial Hospital, Chicago, Illinois Division of Infection Diseases, Department of Medicine, Northwestern University Medical School, Northwestern Memorial Hospital, Chicago, Illinois Clinical Microbiology Laboratory, Northwestern Memorial Hospital, Chicago, Illinois NMH Infection Control and Prevention Project, Northwestern Memorial Hospital, Chicago, Illinois
*
Northwestern University Medical School, Clinical Microbiology Section, Wesley Pavilion, Room 565, 250 East Superior St, Chicago, IL 60611

Abstract

Objective:

To determine the molecular epidemiology of vancomycin-resistant enterococci (VRE) at our medical center in order to identify the extent of strain clonality and possible transmission patterns of this pathogen.

Design:

An important facet of our infection control program includes molecular typing of all clinical and surveillance isolates of VRE to determine transmission patterns in the hospital. Molecular strain typing is performed by restriction endonuclease analysis (REA) of genomic DNA. REA patterns are visually compared to categorize VRE strains into type and subtype designations.

Setting:

A 588-bed, university-affiliated, tertiary-care hospital and a neighboring 155-bed rehabilitation facility.

Results:

From January 1995 through December 1996, 379 VRE isolates were collected from 197 patients. Thirty-three genotypes were determined by REA typing; 15 genotypes were implicated in 29 instances of potential nosocomial transmission. Three major clusters of VRE involving patients on multiple nursing units and two adjacent hospitals were identified. The remaining instances of nosocomial transmission occurred in small patient clusters.

Conclusions:

In conclusion, the VRE epidemic at this medical center is polyclonal. VRE transmission patterns are complex, and, while large clusters do occur, the usual pattern of nosocomial acquisition of this pathogen occurs in the setting of “mini-clusters”.

Type
Original Articles
Copyright
Copyright © The Society for Healthcare Epidemiology of America 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Centers for Disease Control and Prevention. Nosocomial enterococci resistant to vancomycin—US, 1989-1993. MMWR 1993;42:597599.Google Scholar
2. Murray, BE. Vancomycin-resistant enterococci. Am J Med 1997;101:284293.Google Scholar
3. Bodnar, UR, Noskin, GA, Suriano, T, Cooper, I, Reisberg, BE, Peterson, LR Use of in-house studies of molecular epidemiology and full species identffication for controlling spread of vancomycin-resistant Enterococcus faecalis isolates. J Clin Microbiol 1996;34:21292132.Google Scholar
4. Boyce, JM, Opal, SM, Chow, JW, Zervos, MJ, Potter-Bynoe, G, Sherman, CB, et al. Outbreak of multidrug-resistant Enterococcus faecium with transferable vanB class vancomycin resistance. J Clin Microbiol 1994;32:11481153.Google Scholar
5. Handwerger, S, Raucher, B, Altarac, D, Monka, J, Marcinone, S, Singh, KV, et al. Nosocomial outbreak due to Enterococcus faecium highly resistant to vancomycin, penicillin, and gentamicin. Clin Infect Dis 1993;16:750755.Google Scholar
6. Karanfil, LV, Murphy, M, Josephson A, Gaynes, R, Mandel, L, Hill, BC, et al. A cluster of vancomycin-resistant Enterococcus faecium in an intensive care unit. Infect Control Hosp Epidemiol 1992;13:195200.Google Scholar
7. Noskin, GA, Stosor, V, Cooper, I, Peterson, LR. Recovery of vancomycin resistant enterococci on fingertips and environmental surfaces. Infect Control Hosp Epidemiol 1995;16:577581.Google Scholar
8. Livornese, LL Jr, Dias, S, Samel, C, Romanowski, B, Taylor, S, May, P, et al. Hospital-acquired infection with vancomycin-resistant Enterococcus faecium transmitted by electronic thermometers. Ann Intern Med 1992;117:112116.CrossRefGoogle ScholarPubMed
9. Porwancher, R, Sheth A Remphrey, S, Taylor, E, Hinkle, C, Zervos, M. Epidemiological study of hospital-acquired infection with vancomycin-resistant Enterococcus faecium: possible transmission by an electronic ear-probe thermometer. Infect Control Hosp Epidemiol 1997;18:771774.CrossRefGoogle ScholarPubMed
10. Morris, JG Jr, Shay, DK, Hebden, JN, McCarter, RJ Jr, Perdue, BE, Jarvis, W, et al. Enterococci resistant to multiple antimicrobial agents, including vancomycin: establishment of endemnicity in a university medical center. Ann Intern Med 1995;123:250259.Google Scholar
11. Facklam, RR, Collins, MD. Identification of Enterococcus species isolates from human infections by a conventional test scheme. J Clin Microbiol 1989;27:731734.Google Scholar
12. National Committee for Clinical Laboratory Standards. Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically. 4th ed. Approved Standard. Document M7-A4. Villanova, PA: NCCLS; 1997.Google Scholar
13. Hospital Infection Control Practices Advisory Committee. Recommendations for preventing the spread of vancomycin resistance. Infect Control Hosp Epidemiol 1995;16:105113.CrossRefGoogle Scholar
14. Pitcher, DG, Saunders, NA, Owen, RJ. Rapid extraction of bacterial genomic DNA with guanidium thiocyanate. Letters in Applied Microbiology 1989;8:151156.Google Scholar
15. Savor, C, Pfaller, MA, Kruszynski, JA, Hollis, RJ, Noskin, GA, Peterson, LR. Comparison of genomic methods for differentiating strains of Enterococcus faecium: assessment using clinical epidemiologic data. J Clin Microbiol 1998;36:33273331.Google Scholar
16. Rutala, WA APIC guidelines for the selection and use of disinfectants. Am J Infect Control 1996;24:313342.Google Scholar
17. Clabots, CR, Johnson, S, Beton, KM, Matnie, PA, Mulligan, ME, Schaberg, DR, et al. Development of a rapid and efficient restriction endonuclease analysis (REA) typing system for Clostridium difficile and correlation with other typing systems. J Clin Microbiol 1993;31:18701875.Google Scholar
18. Bonten, MJM, Hayden, MK, Nathan, C, van Voorhis, J, Matushek, M, Slaughter, S, et al. Epidemiology of colonization of patients and environment with vancomycin-resistant enterococci. Lancet 1996;348:16151619.Google Scholar
19. Dunne, WM Jr, Wang, W. Clonal dissemination and colony morphotype variation of vancomycin-resistant Enterococcus faecium isolates in metropolitan Detroit, Michigan. J Clin Microbiol 1997;35:388392.Google Scholar
20. Perlada, DE, Smulian, AG, Cushion, MT. Molecular epidemiology and antibiotic susceptibility of enterococci in Cincinnati, Ohio: a prospective citywide survey. J Clin Microbiol 1997;35:23422347.Google Scholar
21. Fridkin, SK, Yokow, DS, Whitney, CG, Onderdonk, A, Hooper, DC. Epidemiology of a dominant clonal strain of vancomycin-resistant Enterococcus faecium at separate hospitals in Boston, Massachusetts. J Clin Microbiol 1998;36:965970.Google Scholar
22. Boyle, JF, Soumakis, SA, Rendo, A, Herrington, JA, Gianarkis, DG, Thurberg, BE, et al. Epidemiologic analysis and genotypie characterization of a nosocomial outbreak of vancomycin-resistant enterococci. J Clin Microbiol 1993;31:12801285.Google Scholar
23. Chow, JW, Kuritza, A, Shlaes, DM, Green, M, Sahm, DF, Zervos, MJ. Clonal spread of vancomycin-resistant Enterococcus faecium between patients in three hospitals in two states. J Clin Microbiol 1993;31:16091611.Google Scholar