Genotype Distribution of CTX-M type Extended-spectrum ?-Lactamases in ESBLs-producing Escherichia coli in Zhengzhou / 中华医院感染学杂志

ABSTRACT

OBJECTIVE To study the genotype distribution of CTX-M type ESBLs in ESBLs-producing Escherichia coli. METHODS All 138 strains of E. coli were collected from the First and Third Affiliated Hospitals,Zhengzhou University from 2006 to 2007. The CTX-M type ESBLs genes were amplified by PCR,the products were sequenced after purification. RESULTS Eighty-two of 138 ESBLs-producing E. coli isolates were classified with CTX-M type-ESBLs genes,and there were 53,27 and 2 strains contained only one type,two types and three types of CTX-M ESBLs,respectively. Among CTX-M type-ESBLs genes,they were identified with CTX-M-1(43 strains),CTX-M-14(56 strains),CTX-M-25(7 strains) and CTX-M-38 (5 strains). CONCLUSIONS The most popular type of CTX-M ESBLs in E. coli is CTX-M14 in Zhengzhou,and two or three kinds of genotypes can exist in 1 strain.