Rapid detection of vancomycin-resistant enterococci from rectal swabs by the Cepheid Xpert vanA/vanB assay

The detection of vancomycin-resistant enterococci using a novel commercial multiplex real-time polymerase chain reaction assay (Xpert™ vanA/vanB, Cepheid, Sunnyvale, CA) was evaluated on 804 rectal swab specimens. Compared to enriched culture, sensitivity and negative predictive value of this method were 100%. Many false-positive results were recovered (sensitivity, 85.4%; positive predictive value, 8.7%), especially for the vanB gene.