耐碳青霉烯类解鸟氨酸拉乌尔菌分子流行病学特征研究  

Molecular epidemiological characteristics of carbapenem-resistant Raoultella ornithinolytica

作　　者：谢小芳[1] 钱费楠 朱志宸 郑毅[1] 杜鸿[1] Xie Xiaofang;Qian Feinan;Zhu Zhichen;Zheng Yi;Du Hong(Department of Clinical Laboratory Center,the Second Affiliated Hospital of Soochow University,Suzhou215004,China)

机构地区：[1]苏州大学附属第二医院医学检验中心,苏州215004

出　　处：《中华检验医学杂志》2024年第11期1306-1313,共8页Chinese Journal of Laboratory Medicine

基　　金：江苏省科技厅重点研发项目(BE2023704);苏州市卫健委重点病种项目(LCZX202106);苏州市卫健委医学创新应用研究项目(SKYD2023108)。

摘　　要：目的了解解鸟氨酸拉乌尔菌的临床流行情况和耐药性,并对碳青霉烯类耐药菌株进行耐药特征分析。方法收集2015年5月至2020年12月经基质辅助激光解吸电离飞行时间质谱技术鉴定的解鸟氨酸拉乌尔菌临床分离株83株,对其中碳青霉烯类耐药的解鸟氨酸拉乌尔菌进行临床信息收集、耐药表型、碳青霉烯酶基因检测;采用脉冲场凝胶电泳(PFGE)对耐药菌株进行同源性分析;全基因组测序(WGS)确定耐药株质粒、耐药基因与毒力基因等分子特征;基于核心单核苷酸多态性(core-SNP)构建系统发育进化树,分析耐药菌株的进化特征。结果83株解鸟氨酸拉乌尔菌中11株对碳青霉烯类抗菌药物耐药。耐药菌株主要来源于外科、重症监护病房和肿瘤科患者的引流液和创面分泌物;除对碳青霉烯类耐药外,11株菌对头孢类、头霉素类、氨曲南耐药性100%,但对左氧氟沙星、替加环素、黏菌素体外活性较好;碳青霉烯酶基因检测结果提示,8株菌携带blaIMP-4基因,3株菌携带blaKPC-2基因,其中1株同时携带blaIMP-4和blaKPC-2基因,2株同时携带blaIMP-4和blaNDM-1基因;PFGE结果提示共有7种带型、4种流行株;WGS提示该11株解鸟氨酸拉乌尔菌携带的质粒复制子类型主要为IncFIA、IncFIB、IncHI1B、IncU、repB和Col,除携带碳青霉烯酶耐药基因外,还携带其他10种不同类型耐药基因,另外,11株菌均检出铁载体相关毒力基因entB、fyu、ybt和irp;系统发育进化分析显示Ro6348和Ro6050、Ro7401和Ro7242、Ro8647和Ro5832、Ro9907和Ro8856分别分组在一起,而Ro8454、Ro7349、Ro7326位于不同的分支上。结论解鸟氨酸拉乌尔菌耐药性与肺炎克雷伯菌相近,携带多种耐药基因,但不同于国内肺炎克雷伯菌,其碳青霉烯酶主要以IMP-4为主。PFGE和系统发育进化分析结果提示该型菌株在院内有相互传播趋势,应引起临床和院感重视。Objective To understand the clinical prevalence and drug resistance of Raoultella ornithinolytica,and to analyze the drug-resistant characteristics of carbapenem-resistant strains.Methods A total of 83 clinical isolates of R.ornithinolytica,identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry between May 2015 and December 2020,were collected.Clinical information,drug-resistant phenotype,and carbapenemase gene of the carbapenem resistant strains were analyzed.Homology of the resistant strains was examined by pulse-field gel electrophoresis(PFGE).The molecular characteristics of plasmids,drug resistance genes and virulence genes were determined by whole genome sequencing(WGS),and a phylogenetic tree was constructed based on core single-nucleotide polymorphisms(core-SNPs)for evolutionary analysis of the carbapenem-resistant strains.Results All 83 clinical isolates were confirmed as R.ornithinolytica,of which 11 strains were resistant to carbapenem antibiotics.The resistant strains were mainly sourced from the drainage fluid and wound secretions of patients in surgery,intensive care unit and oncology department.In addition to carbapenems resistances,the 11 strains were also resistant to cephalosporins,cephamycins,and aztreonam,while maintaining good in vitro activity to levofloxacin,tigecycline and colistin.Carbapenemase gene detection showed that 8 strains carried the bla IMP-4,3 carried bla KPC-2,of which 1 strain carried both bla IMP-4 and bla KPC-2,and 2 strains carried both bla IMP-4 and bla NDM-1.PFGE results showed 7 banding types and 4 epidemic strains.WGS identified plasmid replicon types carried by the 11 strains of R.ornithinolyticus including IncFIA,IncFIB,IncHI1B,IncU,repB and Col,along with 10 additional types of drug resistance genes.Iron carrier related virulence genes entB,fyu,ybt and irp were detected in all carbapenem-resistant strains.Phylogenetic analysis showed that Ro6348 and Ro6050,Ro7401 and Ro7242,Ro8647 and Ro5832,and Ro9907 and Ro8856 were grouped t

关 键 词：碳青霉烯类 解鸟氨酸拉乌尔菌 耐药性 全基因组测序 

分 类 号：R446.5[医药卫生—诊断学]