Epidemiological Characteristics And Resistance Genes Of Carbapenem Resistant Klebsiella Pneumoniae In Zhejiang Province

Objective:Retrospectively investigate the distribution,carbapenemases-encoding genes and molecular epidemiology of carbapenem resistant Klebsiella pneumoniae(CRKP)in Zhejiang province.Methods:A total of 772 clinical isolates of K.pneumoniae isolated from 9 hospitals(Hangzhou,Jiaxing,Shaoxing,Quzhou,Lishui,Huzhou,Wenzhou,Zhoushan,Jinhua)in Zhejiang Province in 2011 were selected,and antimicrobial susceptibility testings were carried out with disk diffusion(all K.pneumoniae isolates)and broth microdilution method(carbapenem resistant isolates screened by disk diffusion).Molecular typing was performed by multilocus sequence typing(MLST)and pulsed field gel electrophoresis(PFGE).PCR was used to detect resistant genes.Results:K.pneumoniae resistant to carbapenems were found in 6 hospitals except hospitals in Wenzhou,Jiaxing and Shaoxing.A total of 48(6.2%)CRKP were screened.Resistance rates of cephalosporins were higher than 95%(cefuroxime and cefotaxime:100%;ceftazidime,cefepime:95.8%),and the rates of aminoglycoside antibiotics such as gentamicin was 62.5%,of quinolone antibiotics such as ciprofloxacin was 83.3%.All the 48 CRKP isolates could be divided into 12 ST types according to the results of MLST,and ST11 was the dominant ST type(30,62.5%).Result of PFGE showed that 48 CRKP isolates could be divided into 15 types.Carbapenemase-encoding genes were detected in 39 isolates(81.3%),among which 37 were identified as blaKPC-2(77.1%)and 2 were blaIMP-4.Conclusion:In 2011,CRKP has appeared in many hospitals in Zhejiang Province,but the overall isolating rate is not high.There are 15 PFGE types and 12 ST types,and ST11 is the most prevalent ST type.The production of KPC-2 is the most important carbapenem resistance mechanism.