产KPC-2型碳青霉烯酶日沟维肠杆菌的耐药性及机制研究  

Study of drug resistance mechanism of KPC-2-type carbapenemase-producing Enterobacter gergoviae

作　　者：孙明洁[1] 李轶[1] 许俊红[1] 

机构地区：[1]河南省人民医院医院感染管理科,河南郑州450003

出　　处：《中华医院感染学杂志》2013年第18期4345-4347,共3页Chinese Journal of Nosocomiology

基　　金：河南省科技厅基础与前沿技术研究项目资助(132300410038)

摘　　要：目的研究一株耐碳青霉烯类药物日沟维肠杆菌中的耐药机制及其耐药基因特点,为临床医师合理选择抗菌药物提供参考。方法采用琼脂稀释法进行药物敏感性试验,聚合酶链反应(PCR)及测序检测β-内酰胺酶耐药基因,等电聚焦电泳(IEF)测定细菌β-内酰胺酶的等电点,质粒电转化试验分析blaKPC基因能否水平传播。结果临床分离日沟维肠杆菌产生TEM-1(pI5.4)、KPC-2(pI6.7)两种β-内酰胺酶耐药基因,blaKPC-2基因可以在细菌之间进行水平传播;临床分离日沟维肠杆菌对多种抗菌药物耐药,电转化株也对亚胺培南和美罗培南等抗菌药物产生耐药性,但其对多种药物的敏感性好于临床株。结论该株日沟维肠杆菌耐碳青霉烯类药物与细菌产生这两种β-内酰胺基因相关。OBJECTIVE To investigate the drug resistance mechanism and the characteristics of drug resistance genes in one strain of carbapenernase-resistant Enterobacter gergoviae so as to guide the reasonable clinical use of antibiotics. METHODS The minimal inhibitory concentrations（MICs） of antirnicrobial agents were determined by agar dilution method. PCR amplification and sequencing were carried out to analyze the encoding genes. Analytical isoelectric focusing was used to measure the pI of the β-lactamaes; electrotransforrnation and electrophoresis of plasrnid were used to analyze the horizontal transmission mechanism of blaKPC in plasmid-mediated KPC earbapenemases. RESULTS Two kinds of β-lactamases were detected in the clinical strain, They were TEM-1（p15. 4） and KPC-2（p16.7）, which were confirmed by sequencing. The blaKPC-2 gene was located on a plasmid and could trans- ferred horizontally. The clinical isolate of E. gergoviae was multidrug-resistant, and the electrotransforrnation strain was also resistant to irnipenern and meropenern and was more susceptible than the clinical isolate to multiple antibiotics. CONCLUSION The production of the two kinds of β-lactarnases genes is the drug resistance mechanism of carbapenern-resistant E. gergoviae.

关 键 词：日沟维肠杆菌 KPC酶 Β-内酰胺酶 碳青霉烯酶 

分 类 号：R978.1[医药卫生—药品]