呼吸道产超广谱β-内酰胺酶分离株耐药基因初步分型

目的了解产超广谱β-内酰胺酶 (ESBLs)呼吸道分离株的主要基因型分布特点.方法用表型确证试验确定临床呼吸道标本中产ESBLs的大肠埃希菌和肺炎克雷伯菌.应用聚合酶链反应(PCR)方法扩增产ESBLs株的bla(TEM)、bla(SHV)和bla(CTX-M)基因.结果 PCR结果显示bla(TEM)、bla(SHV)和bla(CTX-M)基因的总阳性率分别为40 .7%、45.7%和75.3%,其中大肠埃希菌分别为:64.9%、2.7%和91.9%,肺炎克雷伯菌分别为:20.5%、81.8%和61.4%.67.6%的大肠埃希菌和95.5%的肺炎克雷伯菌同时携带多个基因.结论深圳市人民医院呼吸道分离的产ESBLs大肠埃希菌的主要基因型为CTX-M,肺炎克雷伯菌主要基因型为SHV.大多数菌株同时携带多个基因.

Genotypes of ESBLs producing isolates from respiratory tract

Objective To investigate the genotypic character of respiratory tract isolates producing extended spectrum beta-lactamases (ESBLs).Methods ESBLs producing Escherichia coli and Klebsiella pneumoniae isolates were indentified by phenotyic confirmatory test. PCR were using to detect bla(TEM),bla(SHV) and bla(CTX-M) genes.Results The positive rates of TEM,SHV and CTX-M genes of all isolates were 40.7%,45.7% and 91.9% respectively.those of Escherichia coli were 64.9%,2.7% and 91.9% respectively. those of Klebsiella pneumoniae were 20.5%,81.8% and 61.4% respectively. 67.6% of Escherichia coli and 95.5% of Klebsiella pneumoniae had more than one genotype.Conclusions The major genotype of ESBLs-producing Escherichia coli was CTX-M and which of Klebsiella pneumoniae was SHV. Many isolates had more than one genotype.