Detection of Vancomycin resistant enterococci from rectal swab samples by Becton-Dickinson GeneOhm VanR assay and culture at ICU of a tertiary care center in Turkey

Abstract

Vancomycin resistance is due to change in ligase enzyme that destroys the binding of the drug. The gold standard is culture; but now molecular methods have also been developed. The aim was to detect the VRE rate at ICUs by culture and BD GeneOhm™ VanR and compare the results of both assays. 135 perianal swabs were taken from the patients atICUs between January 1(st) 2009 and April 30(th) 2009. Samples were identified by conventional methods and BD GeneOhm VanR assay. In newborn ICU, 41 patients (74.6%) were negative by both methods. Two (3.6%) were positive by both methods. Twelve (21.8%) of them were culture negative and PCR positive. In adult ICU, 73 (91.3%) patients were negative by both methods. Seven patients (8.8%) were positive by molecular method only. This study showed low VRE positivity due to factors like inhibition in PCR or culture negativity due low inoculum for bacterial growth. Early detection of VRE is an important issue especially in ICUs and molecular techniques are important tools; but against all, we still need to confirm this method with culture based techniques and in order to do this further studies with higher number of patients with VRE colonisation are required.