肝移植术后感染大肠埃希菌的DNA多态性与耐药性分析

Analyses of DNA Polymorphism and Drug Resistance of E.coli from Infected Patients after Liver Transplantation

应用随机引物扩增多态性DNA(RAPD)技术分析肝移植术后大肠埃希菌感染株DNA的多态性,并对其进行分型,研究肝移植术后大肠埃希菌感染的流行状况,并探讨大肠埃希菌产超广谱β-内酰胺酶(ESBLs)与基因型之间的关系。应用1条含10个碱基的随机引物对20株大肠埃希菌的DNA进行随机扩增,ESBLs试验使用双纸片协同法。20株大肠埃希菌经RAPD分为11个基因型,ESBLs检测12株大肠埃希菌阳性,ESBLs阳性大肠埃希菌在700 bp有共同条带。肝移植术后感染以内源性感染为主,肠道细菌移位可能是大肠埃希菌感染的一个主要因素,ESBLs阳性检出率高,ESBLs阳性与基因型之间具有相关性。

Random primer of amplified polymorphism DNA （RAPD） technique was used to analyse the infection of E. coli infection strain and its typing after liver transplantation to study the epidemic conditions of the E. coli infection after the transplantation, and to investigate the relation between the production of super-broad spectrum β-1actamast （ESBLs） and genotype. A random primer containing 10 bases was used to amplify 20 strains of E. coli randomly. K-B method was used for determination of ESBLs. The results showed that 20 clinical infected strains of E. coli were RAPD classified into 11 types, and 12 strains were ESBLs positive, Therefore, the post-transplantation E. coli infection was mainly autogenously origin, and translocation of intestinal flora might play a major role. The incidence of ESBLs are high showing correlation with their genotyping.