摘要目的 探讨临床分离的碳青霉烯类耐药肺炎克雷伯菌基因分型和菌株同源性.方法 收集2011年1月至2012年6月临床分离的碳青霉烯类耐药肺炎克雷伯菌175株,采用MIC法检测菌株对药物的敏感性,纸片法表型确证试验检测超广谱β内酰胺酶(ESBL),改良Hodge试验检测碳青霉烯酶表型,PCR、DNA测序以及BLAST比对等方法确定菌株耐药酶基因型,重复序列聚合酶链反应(REP-PCR)分析菌株同源性.结果 175株肺炎克雷伯菌中Hodge试验阳性140株,阳性率80.0％(140/175).102株携带blaKPC-2基因,占58.3％(102/175),6株携带blaIMP-4基因,占3.4％ (6/175).11.4％(20/175)菌株携带blaDHA-1基因.28.6％(50/175)菌株ESBL表型试验阳性.有89.1％(156/175)菌株携带blaSHV基因,63.4％ (111/175)菌株携带blaTEM基因,50.3％(88/175)菌株携带blaCTX-M基因.66.9％(117/175)菌株同时具有3种以上耐药基因.REP-PCR指纹图谱扩增条带数3～8条,产物最长1600bp,最短200 bp,分为12个谱型,其中以G型为主,有71株(40.6％),其次为F型有35株(20.0％).结论 碳青霉烯类耐药肺炎克雷伯菌以blaKPC-2基因型为主,其次为blaIMP-4基因型；ESBL以blaCTX-M-14基因型为主.在某些医院存在克隆株流行,北京A医院与杭州地区流行株不同,北京A医院以G型为主,杭州地区以F型为主.(中华检验医学杂志,2013,36:318-323)

abstractsObjective To investigate genotyping and homology of Carbapenems-resistant Klebsiella pneumonia isolated from clinical specimens.Methods A total of 175 clinical isolates of Carbapenemsresistant Klebsiella pneumoniae were isolated from clinical specimens from January 2011 to June 2012.Antimicrobial susceptibility testing was performed by MIC method according to guidelines of CLSI.Extended-spectrum β-lactamases (ESBLs) were detected by phenotypic confirmatory test.The carbapenemase were confirmed by modified Hodge test (MHT).β-lactamases genes were amplified by polymerase chain reaction (PCR),the PCR products were subjected direct sequencing of both directions,BLAST were preformed to confirm the genotypes of β-lactamases.DNA fingerprinting based on repetitivesequence-based PCR (REP-PCR) to investigate the homology of Carbapenems-resistant Klebsiella pneumonia.Results Of 175 clinical isolates of carbapenems-resistant Klebsiella pneumonia,80.0％ (140/175) strains appeared positive response of MHT.PCR and sequencing analyses showed that 58.3％ (102/175) strains harbored blaKPC.2 genes,3.4％ (6/175) harbored blaIMP-4 genes.There was 11.4％ (20/175) strains which harbored blaDHA-1 genes,and 28.6％ (50/175) strains which produced ESBLs by phenotypic test.There was 89.1％ (156/175) strains which harbored blasHv genes,and 63.4％ (111/175)strains harbored blaTEM genes.There was 50.3％ (88/175) strains which harbored blaCTX-M genes.More than three kinds of resistant genes were detected simultaneously in 66.9％ (117/175) strains.DNA fingerprinting showed that 3 to 8 discernible DNA bands ranging in size from 200 bp to 1600 bp were generated by REP-PCR amplification.According to the results,the 175 strains were categorized into 12 types of gene pattern,in which 71 (40.6％) strains were pattern G,followed by 35(20.0％) strains were pattern F.Conclusions The major genotype causing Carbapenems resistance in Klebsiella pneumoniae is blaKPC-2,followed by blaIMP-4.The major genotype of ESBLs is blaCTX-M-14.There is an Epidemic of clone strains in some hospitals in China.There are genetic difference between the epidemic strains in different area,the epidemic strains is majorly pattern G in the A hospital in Beijing,while pattern F in Hangzhou.(Chin J Lab Med,2013,36:318-323)