The Study Of Carbapenemases In Enterobacteria Ceae And Homplogy Of Carbapenems-resistant Strains

Objectve To study the main mechanism and prevalence of carbapenems-resistance Enterobacteriaceae in our hospital, in order to provide basic datum for the prevention and control of Carbapenems-resistant Enterobacteriaceae strains in our hospital.Methods Thirty isolated Enterobacteriaceae decreasing susceptibility to carbapenems antibiotics were collected in our hospital from June2010to June2012. They were identified by Vitek2Compact. Antimicrobial susceptibility testing were carried out by K-B test. The phenotype of carbapenemase was selected by Modified Hodge test and EDTA double-disk synergy test. The blaNDM-1. blaKPC, blaIMP, blaVIM and blaSME were detected by PCR. The PCR-positive strains were performed homology analysis by Rep-PCR.Results Thirty multi-drug resistant strains were isolated, which came from ICU (22), General surgery (6), Urology(1).Neurology(1). Twenty one strains were positive in Modified Hodge test,twenty three strains were positive in EDTA double-disk synergy test. PCR amplification results showed that14isolates produced NDM-1type carbapenemase, of which12Klebsiella pneumoniae,1Klebsiella oxytoca and1Enterobacter cloacae.blaKPC. blaIMP, blaVIM.blaSME gene were negative in all of the thirty isolates.Conclusion NDM-1type carbapenemases is the major type of carbapenemases in our hospital. There was a small-scale epimedics in ICU.The further research should be given to the mechanisms of carbapenems antibiotics resistance.