浙江地区碳青霉烯类耐药肺炎克雷伯菌分布、流行及耐药基因分析

Distribution, molecular epidemiology and resistance genes of carbapenem resistant KlebsieUa pneumoniae in Zhejiang Province

目的回顾性分析2011年浙江省内碳青霉烯类耐药肺炎克雷伯菌（carbapenem resistant Klebsiella pneumoniae, CRKP）的分布、分子流行病学特征及耐药基因的携带情况。方法选取浙江大学医学院附属邵逸夫医院保存的收集于2011年浙江省内9家医院临床标本中分离的肺炎克雷伯菌772株，采用纸片法和微量肉汤稀释法进行药物敏感试验，PCR检测耐药基因，多位点序列分型和脉冲场凝胶电泳进行分子分型。结果9家医院共筛选到CRKP 48株（6.2%），PCR结果显示有39株携带碳青霉烯类耐药基因，其中37株携带blaKPC-2基因（77.1 %），2株携带blaIMP-4基因。多位点序列分型结果显示ST11为主要ST型（30株，62.5 %），脉冲场凝胶电泳显示48株肺炎克雷伯菌可分为15个克隆型。除温州、嘉兴和绍兴的临床菌株中未分离到碳青霉烯类耐药肺炎克雷伯菌之外，其余6家医院均有此类耐药菌分布。 结论2011年CRKP在浙江省内大部分地区均有分布，产KPC-2型碳青霉烯酶是肺炎克雷伯菌最主要的碳青霉烯类耐药机制，ST11为最流行的ST型。

ObjectiveTo retrospectively investigate the distribution, molecular epidemiology and carbapenemases-encoding genes of carbapenem resistant Klebsiella pneumoniae （CRKP） in Zhejiang Province.MethodsA total of 772 clinical isolates of K. pneumoniae isolated from 9 hospitals in Zhejiang Province in 2011 were selected, and antimicrobial susceptibility testings were carried out with disk diffusion or broth microdilution method. Polymerase chain reaction （PCR） was used to detect resistant genes, and molecular typing was performed by multilocus sequence typing （MLST） and pulsed field gel electrophoresis （PFGE）.ResultsA total of 48 CRKP （6.2%） were screened in 9 hospitals. Carbapenemase-encoding genes were detected in 39 isolates by PCR, among which 37 （77.1%） were identified as blaKPC-2 and 2 were blaIMP-4. MLST showed that ST11 was the dominant ST type （30, 62.5%）. Results of PFGE showed that 48 CRKP can be divided into 15 types. CRKP was found in 6 hospitals except hospitals in Wenzhou, Jiaxing and Shaoxing.ConclusionsIn 2011, CRKP is distributed in most areas of Zhejiang Province. The production of KPC-2 is the most important carbapenem resistance mechanism and ST11 is the most prevalent ST type.