New type F lineage-related Tn1546and avanA/vanBtype vancomycin-resistantEnterococcus faeciumisolated from patients in Dammam, Saudi Arabia during 2006–2007

Abstract

SUMMARYKnowledge regarding vancomycin-resistant enterococci (VRE) from Middle Eastern countries is scarce. We therefore investigated the antimicrobial resistance profiles and genetic relationships of VREEnterococcus faeciumisolates obtained from patients attending the King Fahad Specialist Hospital, Dammam, during 2006–2007. The predominant VRE comprised 20vanB, fivevanAand onevanA/vanBtype isolates, which tended to fall into two genetic clusters that were identifiable phenotypically by their susceptibility to tetracycline. Multi-locus sequence typing of a random selection of isolates showed that they were part of clonal cluster 17, showing the importance of this genotype in nosocomial VRE infections in Saudi Arabia. Further analysis showed that four of thevanAgenotype isolates possessed a new type F Tn1546transposon, associated with IS1216Vand IS1251. Finally,E. faecium vanA/Bisolates are rarely reported in the clinical setting including in Saudi Arabia.