肾移植后尿路大肠杆菌感染特征及毒力因子的检测

The infection characteristics of urinary E.coli after kidney transplantation and virulence factor detection

目的 分析肾移植术后尿路大肠杆菌感染的临床特点及致病毒力因子的分布.方法 2014年1月至2016年6月实施公民逝世后器官捐献（DCD）肾移植255例,术后发生尿路感染45例,其中大肠杆菌感染32例,分别对32例大肠杆菌感染进行分离培养,用实时聚合酶链反应（PCR）和多重PCR方法检测32株尿源大肠杆菌菌种的毒力因子基因：产气杆菌素毒力因子基因Aer、溶血素毒力因子基因hly、铁抑制蛋白毒力因子基因irp2和禽产气杆菌素毒力因子基因iucD等.结果 肾移植后大肠杆菌感染占尿路感染的71.1％（32/45）,按照感染来源分院内感染组9例,社区感染组23例.院内感染组大肠杆菌菌种的毒力因子基因：产气杆菌素毒力因子基因Aer、溶血素毒力因子基因hly、铁抑制蛋白毒力因子基因irp2和禽产气杆菌素毒力因子基因iucD的检出率分别为66.7％、33.3％、88.9％和77.8％;社区感染组大肠杆菌菌种的毒力因子基因：产气杆菌素毒力因子基因Aer、溶血素毒力因子基因hly、铁抑制蛋白毒力因子基因irp2和禽产气杆菌素毒力因子基因iucD的检出率分别为30.4％、8.70％、39.1％和34.7％;比较2组间4种毒力因子的检出率,P＜0.05,差异有统计学意义;院内感染组大肠杆菌的大肠杆菌4种毒力因子的阳性株数均明显高于社区感染组.总耐药率为84.38％,两组的多重耐药率比较,P＜0.01,差异有统计学意义.结论 大肠杆菌感染是肾移植术后尿路感染的主要致病菌,特别是院内感染,大肠杆菌毒力因子检出率高,多重耐药性突出,应引起临床上的高度重视.

Objective To analyze the clinical characteristics of urinary tract infection after kidney transplantation and to analyze the distribution of pathogenic virulence factors.Methods From January 2014 to June 2016,a total of 255 cases were subjected to DCD renal transplantation in our center,and 45 cases of urinary tract infection occurred after operation.Among them,urinary tract E.coli infection occurred in 32 cases.The virulence factors gene aer,hly,irp2 and iucD in the 32 strains of E.coli isolated from urine were tested using PCR and multiple PCR.Results Thirty-two cases （71.1％） of urinary tract infection after renal transplantation was caused by E.coli,and divided into 9 cases of nosocomial infection group,and 23 cases of community-acquired group.The positive rate for aer,hly,irp2 and iucD in Nosocomial infection group was 66.7％,33.3％,88.9％ and 77.8％,and that in community-acquired group was 30.4％,8.70％,39.1％ and 34.7％,respectively.There were statistically significant differences among four kinds of virulence factors between two groups （P＜0.05）.The positive rate of virulence factors was significantly higher in nosocomial infection group than in community-acquired groups.The total resistance rate was 84.38％,and there was significarit difference in multi-drug resistance rate between two groups （P＜0.01）.Conclusion E.coli is the main pathogenic bacteria of urinary tract infection after renal transplantation,especially nosocomial infections.The detection rate of virulence factor is high,and the multiple drug resistance is outstanding,so the attention should be paid clinically.