Surveillance for vancomycin-resistant enterococci: type, rates, costs, and implications.
OBJECTIVE
To evaluate 2 active surveillance strategies for detection of enteric vancomycin-resistant enterococci (VRE) in an intensive care unit (ICU).


METHODS
Thirty-month prospective observational study.


METHODS
ICU at a university-affiliated referral center.


METHODS
All patients with an ICU stay of 24 hours or more were eligible for the study.


METHODS
Clinical active surveillance (CAS), involving culture of a rectal swab specimen for detection of VRE, was performed on admission, weekly while the patient was in the ICU, and at discharge. Laboratory-based active surveillance (LAS), involving culture of a stool specimen for detection of VRE, was performed on stool samples submitted for Clostridium difficile toxin detection.


RESULTS
Enteric colonization with VRE was detected in 309 (17%) of 1,872 patients. The CAS method initially detected 280 (91%) of the 309 patients colonized with VRE, compared with 25 patients (8%) detected by LAS; colonization in 4 patients (1%) was initially detected by analysis of other clinical specimens. Most patients with colonization (76%) would have gone undetected by LAS alone, whereas use of the CAS method exclusively would have missed only 3 patients (1%) who were colonized. CAS cost Dollars 1,913 per month, or Dollars 57,395 for the 30-month study period. Cost savings of CAS from preventing cases of VRE colonization and bacteremia were estimated to range from Dollars 56,258 to Dollars 303,334 per month.


CONCLUSIONS
A patient-based CAS strategy for detection of enteric colonization with VRE was superior to LAS. In this high-risk setting, CAS appeared to be the most efficient and cost-effective surveillance method. The modest costs of CAS were offset by the averted costs associated with the prevention of VRE colonization and bacteremia.
Shadel
Brooke N
BN
Institute for Bio-Security, School of Public Health, Saint Louis University, Saint Louis, MO 63104, USA. shadebn@slu.edu
Puzniak
Laura A
LA
Gillespie
Kathleen N
KN
Lawrence
Steven J
SJ
Kollef
Marin
M
Mundy
Linda M
LM
D003362:Cost-Benefit Analysis; D016983:Enterococcus / Q000145:classification / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology; D006801:Humans; D017053:Infection Control / Q000191:economics; D007362:Intensive Care Units; D008297:Male; D008828:Microbiological Techniques / Q000191:economics*; D008875:Middle Aged; D011446:Prospective Studies; D020713:Vancomycin Resistance