Objective       To determine the virulence genes

resistance transposon types and infection risk factors of Vancomycin-resistant Enterococcus faecium (VREfm) isolates.       Methods      Eighteen VREfm isolates were collected in our hospital from January 2012 to February 2014

and all isolates were validated by broth dilution susceptibility testing. The minimum inhibitory concentrations (MIC) of the 13 antimicrobial agents were tested by using VITEK 2 compact. The Van resistance genes and virulence genes were detected by multiplex PCR. The resistant transposon Tn1546 were analyzed by overlapping PCR

and the sequence type was identified by multilocus sequence typing (MLST). A case-control study was conducted to investigate the risk factors for VREfm infection.       Results       All 18 strains of VREfm showed the genotype and phenotype of VanA

had a 100% rate of resistance to penicillin

ampicillin

ciprofloxacin

and a 100% rate of sensitivity to tigecycline

linezolid and quinupristin/dalfopristin. PCR analysis revealed that the presences of virulence genes were 94.4% in acm

88.9% in  esp

and 83.3% in hyl in the VREfm isolates. There were 4 different transposon types of Tn1546 identified. MLST analysis identified 5 different sequence types

and all belonged to clonal complex 17 (CC17). The presence of virulence genes esp

referred patients

urinary tract infection

and prior use of vancomycin were independent risk factors for the acquisition of VREfm.       Conclusion       All 18 strains of VREfm are multi-drug resistant

and belong to CC17. The high presence of virulence gene esp is significantly associated with VREfm.