猪源分离大肠埃希菌产ESBLs的基因型及耐药性分析

为了解上海地区规模化猪场分离的大肠埃希菌产超广谱β-内酰胺酶（ESBLs）的分离率、耐药性和基因型，收集2010年9月-2011年3月从上海地区10个规模化养猪场分离的296株大肠埃希菌，采用微量肉汤稀释法进行药敏试验以及PCR技术分别检测TEM、CTX-M、OXA和SHV基因。在296株大肠埃希菌中，52株大肠埃希菌产ESBLs，产酶率为17．6％。在52株ESBLs菌株中，46株为TEM型，占88．5％；15株为CTX—M型，占28．8％；11株为同时携带TEM型和CTX—M型，占21．2％。大肠埃希菌产ESBLs株对10种常用抗菌药物的耐药性较为严重，而且存在多重耐药；上海地区猪源大肠埃希菌产ESBLs株流行的主要基因型为TEM型和CTX—M型。

Analysis of ESBLs Genotype and Antimicrobial Resistance of ESBLs-Producing Escherichia Coli from Pigs

To investigate the isolation rate, antibiotic susceptibility and ESBLs＇ genotypes of Escherichia coli strains isolated from ten large - scale pig farms in Shanghai, 296 strains of Escherichia coli were collected from September 2010 to March 2011. Susceptibility testing was performed by broth microdilution, and the genotypes of TEM, CTX -M, OXA and SHV genes were analyzed by PCR. There were 52 strains expressing ESBLs and the isolated rate was 17.6%. There were 46 strains expressing TEM gene （ 88.5% ） , 15 strains expressing CTX - M gene （28.8%） , 11 strains expressing both TEM gene and CTX - M gene （21.2%） among 52 strains. The susceptibility testing against 10 antimicrobial agents of ESBLs - producing Escherichia coli was serious and multidrug resistant. This study showed that TEM type and CTX - M type were predominant genotypes of ESBLs in Escherichia coli strains isolated from pigs.