老年患者尿路感染大肠埃希菌耐药性及分子流行病学分析

Drug resistance and molecular epidemiological analysis of Escherichia coli in elderly patients with urinary tract infection

目的了解本院老年患者尿路感染大肠埃希菌耐药性及分子流行病学特征,为临床合理用药提供依据。方法收集2017年1月—2019年12月于浙江省杭州市富阳区第一人民医院就诊的年龄≥50岁尿路感染患者分离的大肠埃希菌99株。采用VITEK 2 Compact 60全自动细菌鉴定和药敏系统仪对细菌进行鉴定及药物敏感性试验。采用多位点序列分型对细菌的分子流行病学进行分析。结果 99株大肠埃希菌中的ESBLs检出率为53.7%,大肠埃希菌对替加环素的敏感度最高(100.0%),其次为碳青霉烯类抗生素。产ESBLs菌株对头孢菌素类的耐药性明显高于非产ESBLs菌株(P <0.05)。多位点序列分型显示共检出33个ST型,以ST53最为常见(20株,20.2%);其次为ST43、ST506和ST8,分别占9.1%、8.1%和7.1%。结论本院老年患者尿路感染大肠埃希菌以ST53型为主,其中产ESBLs大肠埃希菌的耐药性更加严重,临床上应根据药敏结果选择合适的抗菌药物,并对产ESBLs菌株进行定期监测。

Objective To investigate the drug resistance and molecular epidemiological characteristics of Escherichia coli in elderly patients with urinary tract infection in our hospital,so as to provide basis for clinical rational drug use. Methods Ninety-nine E. coli strains were collected from elderly patients( ≥50) with urinary tract infections during January 2017 to December2019,in the First People’s Hospital of Fuyang Hangzhou,Zhejiang. Identification of bacteria and antibiotic susceptibility tests were performed via VITEK2 Compact 60 automatic system. The molecular epidemiology of bacteria was analyzed by multi-locus sequence typing( MLST). Results The detection rate of ESBLs-producing E. coli was 53. 7%. Overall,E. coli showed the highest susceptibility to tigecycline( 100. 0%),followed by carbapenems. ESBLs-producing E. coli isolates showed a significantly higher resistant rate to cephalosporins than non-ESBLs-producing E. coli isolates( P < 0. 05). MLST indicated that a total of 33 STs were identified. ST53 was the dominant strain( 20/99,20. 2%),followed by ST43( 9. 1%),ST506( 8. 1%)and ST8( 7. 1%). Conclusion The main type of E. coli strains in elderly patients with urinary tract infection in our hospital is ST53,in which the drug resistance of ESBLs-producing E. coli is more serious. Appropriate antimicrobial agents should be selected according to the results of drug sensitivity,and ESBLs-producing strains should be monitored regularly.