蚌埠地区产超广谱β-内酰胺酶菌株CTX-M型耐药基因的分布

Distribution of Resistant CTX-M Genotypes of Extended-spectrum β-Lactamases-producing Klebsiella pneumoniae and Escherichia coli Strains in Bengbu,Anhui Province:A Preliminary Study

目的了解蚌埠市部分医院临床分离产超广谱β-内酰胺酶大肠埃希菌和肺炎克雷伯菌中CTX-M型ESBLs基因分布情况。方法标本为蚌埠市3所医院2003年4月-2004年4月间,临床分离产ESBLs肺炎克雷伯菌和大肠埃希菌147株;采用聚合酶链反应(PCR)扩增产CTX-M型ESBLs菌株基因;按Sanger双脱氧末端终止法,用自动测序仪对其进行测序以鉴定基因型。结果147株产ESBLs菌株中有92株携带CTX-M型ESBLs基因,其中CTX-M-14型52株、CTX-M-3型20株、CTX-M-15型20株。结论蚌埠市部分医院产CTX-M型ESBLs大肠埃希菌和肺炎克雷伯菌检出率较高,主要为CTX-M-14型。

OBJECTIVE To study the genotype distribution of CTX-M-type ESBLs in extended-spectrum β-lactamases（ESBLs）-producing Klebsiella pneumoniae and Escherichia coli strains isolated from four hospitals in Bengbu Anhui Province. METHODS Totally 147 strains of ESBLs-producing K. pneumoniae and E. coli strains were collected from 4 general hospitals, such as the Affiliated Hospital of Bengbu Medical College, the First People＇s Hospital of Bengbu, and the Second People＇s Hospital of Bengbu and the Third People＇s Hospital of Bengbu, between Apr 2003 and Apr 2004. The CTX-M-type ESBLs genes were amplified by polymerase chain reaction （PCR）, then sequenced by Sanger＇s dideoxy chain termination composition method. RFSULTS Ninety two of 147 ESBLs-producing K. pneumoniae and ESBLs-producing E. coli isolates were classified with CTX-M-typeESBLs genes. We sequenced all of them. The results showed that there were 52, 20 and 20 strains carried CTXM-14, CTX-M-3 or CTX-M-15, respectively. CONCLUSIONS The rate of CTX-M-type-ESBLs-producing K. pneumoniae and E. coli reaches a high level in the hospitals in Bengbu. CTX-M-14-type-ESBLs gene is predominant.