The epidemiology of vancomycin-resistant Enterococcus colonization in a medical intensive care unit.
OBJECTIVE
To determine the epidemiology of colonization with vancomycin-resistant Enterococcus (VRE) among intensive care unit (ICU) patients.


METHODS
Ten-month prospective cohort study.


METHODS
A 19-bed medical ICU of a 1,440-bed teaching hospital.


METHODS
Patients admitted to the ICU had rectal swab cultures for VRE on admission and weekly thereafter. VRE-positive patients were cared for using contact precautions. Clinical data, including microbiology reports, were collected prospectively during the ICU stay.


RESULTS
Of 519 patients who had admission stool cultures, 127 (25%) had cultures that were positive for VRE. Risk factors for VRE colonization identified by multiple logistic regression analysis were hospital stay greater than 3 days prior to ICU admission (adjusted odds ratio [AOR], 3.6; 95% confidence interval [CI95], 2.3 to 5.7), chronic dialysis (AOR, 2.4; CI95, 1.2 to 4.5), and having been admitted to the study hospital one to two times (AOR, 2.3; CI95, 1.4 to 3.8) or more than two times (AOR, 6.5; CI95, 3.7 to 11.6) within the past 12 months. Of the 352 VRE-negative patients who had one or more follow-up cultures, 74 (21%) became VRE positive during their ICU stay (27 cases per 1,000 patient-ICU days).


CONCLUSIONS
The prevalence of VRE culture positivity on ICU admission was high and a sizable fraction of ICU patients became VRE positive during their ICU stay despite contact precautions for VRE-positive patients. This was likely due in large part to prior VRE exposures in the rest of the hospital where these control measures were not being used.
Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
David K
DK
Warren
Marin H
MH
Kollef
Sondra M
SM
Seiler
Scott K
SK
Fridkin
Victoria J
VJ
Fraser
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003428:Cross Infection; D016983:Enterococcus / Q000187:drug effects* / Q000302:isolation & purification / Q000472:pathogenicity*; D005260:Female; D006784:Hospitals, Teaching / Q000706:statistics & numerical data; D006801:Humans; D017053:Infection Control; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D020713:Vancomycin Resistance