医院获得性尿路感染肠球菌耐药性与毒力基因型相关研究

摘要

Objective To investigate the distribution of virulence factors and drug resistance of Enterococcus in hospital‐acquired urinary tract infections ,and their correlation to provide the basis for rationally using antibacterial drugs and controlling infection .Methods 74 strains of Enterococcus isolated from clinical specimens of urinary tract infection were performed the bacterial strain identification and the antimicrobial susceptibility test was conducted by the K‐B method .Virulence genes of cylL‐L ,cylL‐S ,cylL‐A ,esp ,acm ,gelE ,asa‐I ,cpd and ace were detected by PCR . Results Among 74 strains of enterococcal ,45(60 .8% ) strains and 29(39 .2% ) strains were E .faecalis and E .faeci‐um ,respectively .The resistance rates of Enterococci isolates to penicillin G ,ampicillin and ciprofloxacin were 89 .66% ,89 .66% and 79 .3% ,which were significantly higher than that of E .faecalis .Among E .faecalis ,the resist‐ance rate was 46 .67% to gentamicin ,53 .33% to tetracycline ,which were slightly higher than that of E .faecium .The positive rates of cylL‐L ,cylL‐S ,cylL‐A ,esp ,acm ,gelE ,asa‐1 ,cpd ,ace were 24 .32% ,44 .59% ,22 .97% ,44 .59% , 60 .81% ,22 .97% ,25 .67% ,22 .97% and 9 .46% ,respectively .A significant correlation was found between distribu‐tion of virulence genes and antimicrobial resistance of E .faecium(P<0 .05) .Conclusion E .faecalis is the predomi‐nant species in hospital‐acquired urinary infection ;the majority of E .faecium was multidrug‐resistant ;E .faecalis has more virulence genes than E .faecium .There is a close relationship between the virulence genes and the drug resist‐ance .Thus it is necessary for clinic to pay attention to the reasonable use of antibacterial drugs so as to prevent the e‐mergence and spread of Enterococcus .%目的：研究医院获得性尿路感染肠球菌毒力因子和耐药分布，以及两者间的关系，为临床合理使用抗菌药物和控制感染提供依据。方法分离出临床尿路感染标本中74株肠球菌进行菌株鉴定，采用纸片扩散法（K‐B法）做药物敏感试验；PCR检测cylL‐L、cylL‐S、cylL‐A、esp、acm、gelE、asa‐I、cpd、ace毒力基因。结果74株肠球菌中有粪肠球菌45株（60．8％），屎肠球菌29株（39．2％）。屎肠球菌对青霉素G、氨苄西林、环丙沙星耐药率分别为89．66％、89．66％、79．31％，明显高于粪肠球菌。粪肠球菌对庆大霉素120、四环素耐药率分别为46．67％、53．33％，略高于屎肠球菌。cylL‐L、cylL‐S、cylL‐A、esp、acm、gelE、asa‐I、cpd、ace 毒力基因的阳性率分别为24．32％、44．59％、22．97％、44．59％、60．81％、22．97％、25．67％、22．97％、9．46％。屎肠球菌毒力基因分布与耐药性间差异有统计学意义（P＜0．05）。结论粪肠球菌是医院获得性尿路感染的主要肠球菌，屎肠球菌表现为多重耐药，粪肠球菌携带更多的毒力因子，屎肠球菌毒力基因数与耐药性之间密切相关，临床应注意抗菌药物的合理应用，防止肠球菌耐药性的产生和传播。