广州地区肺炎克雷伯菌携带CTX-M-14质粒同源性分析  

Analysis on homology of plasmid carried by CTX-14-producing Klbsiella pneumoniae in Guangzhou

作　　者：李小燕[1] 卓超[2] 黎晓强[2] 冯景宇[2] 沈妙娜[2] 

机构地区：[1]广州医学院第四附属医院检验科,广州510182 [2]广州呼吸疾病研究所,广州510120

出　　处：《临床检验杂志》2012年第9期700-703,712,共5页Chinese Journal of Clinical Laboratory Science

基　　金：广州医学院青年基金项目(广医科[2010]1号);广州市教育局青年项目(10A271)

摘　　要：目的研究广州肺炎克雷伯菌(Klebsiella pneumonia,Kp)CTX-M-14型超广谱β-内酰胺酶(ESBLs)的质粒同源性特征。方法收集2007～2008年广州地区9家医院临床分离的产ESBLs肺炎克雷伯菌,PCR检测ESBLs分子表型;用肠杆菌科基因间重复序列PCR(Enterobacteriaceae repetive intergenic consensus-PCR,ERIC-PCR)分析产CTX-M-14型ESBLs菌株的分子同源性;取产CTX-M-14型ESBLs的Kp的所有非克隆株,通过结合试验、质粒图谱、PCR分析blaCTX-M-14基因环境。结果产ESBLsKp共181株,69.1%(125/181)的产ESBLs株为CTX-M表型;其中产CTX-M-14型ESBLs株的检出率为28.2%(51/181),经ERIC-PCR分析,共分为33个基因型;基因环境显示,75.7%(25/33)blaCTX-M-14位于90 kb的可接合质粒上,其他耐药基因blaSHV、blaDHA-1、blaOXA-1、qnr、aac(6')-Ib-cr等均未检到;有28株菌的blaCTX-M-14位于ISEcp1-like插入序列下游,ISEcp1-like末端与blaCTX-M-14间距均为42 bp,有2株菌ISEcp1末端与blaCTX-M-14起始区间距也为42 bp;但在ISECP1中间有一个S10插入序列。结论广州地区ESBLs主要分子表型为CTX-M型,主要流行为CTX-M-14型,携blaCTX-M-14质粒的传播,可能是本地区CTX-M型ESBLs高发生率的主要原因。Objective To research homology and of the genetic environment of plasmid carry CTX-M-14 extended spectrum beta-lactamase（ESBLs） in Klbsiella pneumoniae from Guangzhou.Methods Klbsiella pneumoniae with ESBLs were collected from nine hospitals located in Guangzhou from 2007 to 2008.The phylogenies of CTX-M type of ESBLs were detected by PCR.The cloned relation of producing CTX-M-14 ESBLs strains were detected through enterobacterial repetitive intergenic consensus PCR（ERIC-PCR）.To analysis generic environment of CTX-M-14 by conjugation test,plasmid analysis and PCR.Results 181 ESBLs-producing isolates of Klbsiella pneumoniae were collected.69.1%（125/181）detected strains producing CTX-M-type ESBLs.Among them,28.2%（51/181）were CTX-M-14 ESBLs.The 51 strains were classified into 33 genotypes by ERIC-PCR.Furthermore,75.7%（25/33） blaCTX-M-14 genes were found at 90 kb-conjugative plasmid,about the others,no blaSHV、blaDHA-1、blaOXA-1、qnr、aac（6′-14 gene,were detected in 28 CTX-M-14 positive strains,and the distances between the end of ISEcpllike insertion sequence and the start codon of blaCTX-M-14 were equal,with 42 base pair.But ISECP1 was interrupted by S10 sequences in two strains.Conclusion CTX-M-14 is still the most common genotype of ESBLs in Guangzhou,but the high prevalence of CTX-M type ESBLs maybe caused by the dissemination of plasmid with CTX-M-14.

关 键 词：肺炎克雷伯菌 超广谱Β-内酰胺酶 CTX-M-14 基因型 

分 类 号：R446.5[医药卫生—诊断学]