从大肠埃希菌和肺炎克雷伯菌中检出质粒介导的AmpC DHA-1型β内酰胺酶基因(英文)  

Identification of plasmid-mediated AmpC gene, blaDHA-1 from clinical isolates of Escherichia coli and Klebsiella pneumoniae

作　　者：王煜[1] 李振华[2] 

机构地区：[1]中国医科大学附属盛京医院急诊科,辽宁沈阳110004 [2]中国医科大学附属第一医院呼吸疾病研究所,辽宁沈阳110001

出　　处：《中国现代医学杂志》2008年第16期2273-2277,共5页China Journal of Modern Medicine

摘　　要：目的了解产质粒介导AmpC酶大肠埃希菌和肺炎克雷伯菌的耐药性和基因型。方法收集2002年1月-2004年5月间我院呼吸科临床标本中分离的大肠埃希菌和肺炎克雷伯菌共110株,用酶提取物三维试验检测AmpC酶;用等电聚焦电泳、耐药质粒电转化试验、聚合酶链反应(PCR)及测序确定AmpC酶基因型。结果大肠埃希菌和肺炎克雷伯菌中AmpC酶检出率分别为9.30%和4.48%。药敏试验显示产酶株对头孢西丁全部耐药,对第三代头孢菌素、酶抑制剂、氨曲南、阿米卡星及环丙沙星均有不同程度耐药,对头孢吡肟及亚胺培南较敏感。7株产AmpC酶菌株中有5株通过电转化试验可将头孢西丁耐药性传递给受体菌,经PCR扩增和测序证实为质粒介导DHA-1型AmpC酶。结论我院临床分离的大肠埃希菌和肺炎克雷伯菌中已经出现产质粒介导AmpC酶菌株,其耐药性能够水平传播,给临床抗感染治疗带来重大威胁。[Objective] To investigate the susceptibility and genotype characteristics of Escherichia coli and Klebsiella pneumoniae producing plasmid-mediated AmpC β-lactamase. [Methods] A total of 110 strains of Escherichia coli and Klebsiella pneumoniae were collected from the patients hospitalized in our respiratory ward from January 2002 to May 2004. The isolates harboring AmpC β-lactamase were detected by three-dimensional test, isoelectric focusing analysis, electroporation and PCR, the PCR products were sequenced subsequently. [Results] Am-pC enzyme was detected in 9.30% of Esoherichia coli and 4.48% of Klebsiella pneumoniae. The susceptibility test showed 7 isolates producing plasmid-mediated AmpC β-lactarnase were all resistant to cefoxitin, part of these strains were resistant to the thlrd-generation Cephalosporins, β-lactamase combined with the β-lactamase inhibitors, Aztreonam,Amikacin and Ciprofloxacin, most of them were susceptible to cefeime and imipenem. 3 strains of Klebsiella pneumoniae and 2 strains of Escherichia coli transferred cefoxitin-resistance to recipients by electroporation. Results of PCR and DNA sequencing verified them to be DHA-1 AmpC β-lactamase.[Conclusions] In Eseherichia coli and Klebsiella pneumoniae isolated in our hospital, there are strains producing plasmid-mediated AmpC β-lactamase, which gene can be transferred horizontally. This brings us great menace in antibiotic therapy.

关 键 词：质粒 AMPC酶 大肠埃希菌 肺炎克雷伯菌 基因 

分 类 号：R446.5[医药卫生—诊断学]