阴沟肠杆菌流行菌株产超广谱β-内酰胺酶分析

ESBLs Produced by Enterobacter cloacae

目的研究江苏苏中地区阴沟肠杆菌流行株产超广谱β-内酰胺酶(ESBLs)的状况。方法采用改良的双纸片法(MDDT)进行ESBLs的初筛;以ESBLs引物(CTX-M、CTXM-1、CTX-M-2、CTX-M-9、SHV、TEM、VEB、PER型)进行PCR扩增,对扩增产物进行序列分析。结果MDDT初筛结果证明该菌株产超广谱β-内酰胺酶,CTX-M型ESBLs引物有扩增产物,序列分析表明该株阴沟肠杆菌携带CTX-M-3型ESBLs。结论江苏苏中地区阴沟肠杆菌流行株产CTX-M-3型ESBLs,是造成该流行株对三代头孢菌素耐药的重要原因。

OBJECTIVE To investigate the ESBLs produced by clinical strains of Enterobacter cloacae. METHODS Production of ESBLs was identified with modification of the double-disk test （MDDT）. Eight kinds of primers （CTX-M,CTXM-1, CTX-M-2, CTX-M-9, SHV, TEM, VEB, and PER） were used for the PCR amplification. Gene clone and DNA sequencing were performed then. RESULTS The result of MDDT was positive, amplicons were gained by PCR amplification with CTXM-1. DNA sequencing of amplicons of this strain revealed ESBLs of CTX-M-3. CONCLUSIONS ESBLs are the important reason for E. cloacae resisting to the third-generation cephalosporins.