Background: Vancomycin-resistant enterococci (VRE) are the important nosocomial pathogens worldwide. The aim of this study was to identify the prevalence of VRE strains in fecal samples isolated from ICU patients and the associated risk factors.

Materials and Methods: In this cross-sectional study, 156 fecal samples were collected from three sectors of ICU at Kashan Shahid-Beheshti hospital from November 2011 to April 2012. Enterococci were detected in samples using the Gram stain and biochemical tests such as catalase reaction, pyrro- lidonyl arylamidase (PYR) and hydrolyze bile esculin . Antibiotic sensitivity test was done by Kirby-Bauer method for the detection of phenotypic resistance.

Results: Fifty-eight out of 135 (43%) patients were colonized with VRE . Van A, B and C phenotypes were 79.3%, 17.2% and 3.5%, respectively. Ninety-four percent of VRE-positive patients had used antibiotics (P=0.037). VRE colonization was associated with the use of 3-4 types of antibiotics (59.2%) and 1-2 types of antibiotics (35.4% P=0.009) and also with prolonged hospitalization . Moreover, no significant association was seen between VRE colonization and the use of corticosteroids, diabetes, history of hospitalization and the type of diseases.

Conclusion: The risk factors for VRE colonization were the use of antibiotics, especially using 3-4 types of antibiotics and prolonged hospitalization.