大肠埃希菌血流感染产ESBLs株分子流行机制  

Molecular epidemic mechanisms of ESBLS⁃producing strains in bloodstream infections caused by Escherichia coli

作　　者：刘伟阳 王燕[1] 邱淑妍 朱丛 杨小兰 赵毅[1] LIU Weiyang;WANG Yan;QIU Shuyan;ZHU Cong;YANG Xiaolan;ZHAO Yi(Department of Microbiology and Immunology,School of Basic Medicine,Guangdong Medical Universi-ty,Dongguan,Guangdong,China,523808;Department of Laboratory Medicine,Huizhou Third People's Hospital,Huizhou,Guangdong,China,516002)

机构地区：[1]广东医科大学基础医学院微生物与免疫学教研室,广东东莞523808 [2]惠州市第三人民医院检验科,广东惠州516002

出　　处：《分子诊断与治疗杂志》2024年第3期573-577,共5页Journal of Molecular Diagnostics and Therapy

基　　金：惠州市医疗卫生领域科技计划项目(2022CZ010228)。

摘　　要：目的 调查分析大肠埃希菌血流感染产超广谱β-内酰胺酶(ESBLs)株分子流行机制,阐明不同耐药基因介导的耐药情况。方法 收集惠州市第三人民医院2019年1月至2022年12月期间血流感染住院患者中分离的ESBLs阳性大肠埃希菌株50例,通过聚合酶链式反应(PCR)扩增法检测菌株耐药基因表达情况,并选取部分扩增阳性产物外送测序,分析其基因亚型及对应耐药性。结果 50株ESBLs阳性大肠埃希菌株中有45株菌携带有blaCTX-M基因,占比90.00%(45/50),30株菌携带有blaTEM基因,占60.00%(30/50);CTX-M基因中16株为CTX-M-1亚群,占35.56%(16/45),29株为CTX-M-9亚群,占64.4%(29/45)。未检出blaSHV基因。经测序,CTX-M-1亚群以CTX-M-15为主,CTX-M-9亚群以CTX-M-14亚型为主。CTX-M-9组菌株头孢他啶及头孢吡肟耐药率低于CTX-M-1组,差异有统计学意义(P<0.05)。结论 惠州地区ESBLss阳性大肠埃希菌株耐药基因以CTX-M型为主,且以CTX-M-9亚群为主要类型,而CTX-M-9亚群以CTX-M-14亚型为主,CTX-M-14亚型对头孢他啶和头孢吡肟耐药率低于CTX-M-1亚群及CTX-M-15亚型。Objective To investigate and analyze the molecular epidemic mechanisms of Esche-richia coli bloodstream infection producing super-broad spectrumβ-lactamase(ESBLs)strains and elucidate the drug resistance mediated by different drug resistance genes.Methods Fifty ESBLS-positive Escherichia coli strains were isolated from hospitalized patients with bloodstream infection from January 2019 to December 2022 at Huizhou Third People's Hospital.The expression of drug resistance genes in these strains was detected through polymerase chain reaction(PCR)amplification,and some of the positively amplified products were sent for sequencing to determine gene subtypes and corresponding drug resistance patterns.Results 45 out of the 50 Escherichia coli strains tested positive for ESBLs,carrying the blaCTX-M gene,which accounted for 90.00%(45/50),while 30 strains carried the blaTEM gene,accounting for 60.00%(30/50).Within the CTX-M genes,16 strains belonged to the CTX-M-1 subgroup,making up 35.56%(16/45),and 29 strains belonged to the CTX-M-9 subgroup,accounting for 64.4%(29/45).No blaSHV gene was found.Upon sequencing,it was revealed that the CTX-M-1 subgroup was primarily composed of the CTX-M-15 subtype,while the CTX-M-9 subgroup was dominated by CTX-M-14 subtype.The resistance rates of ceftazidime and cefepime in the CTX-M-9 group were lower compared to those in the CTX-M-1 group,with statistically significant differences(P<0.05).Conclusion In Huizhou,ESBLSS-positive Escherichia coli strains,the dominant drug resistance gene,is CTX-M type,with the CTX-M-9 subgroup being the main type.Within the CTX-M-9 subgroup,the dominant subtype is CTX-M-14.The resistance rate of the CTX-M-14 subtype to ceftazidime and cefepime was lower than that of the CTX-M-1 subgroup and CTX-M-15 subtype.

关 键 词：大肠埃希菌 血流感染 耐药性分析 耐药基因 分型 

分 类 号：R446.5[医药卫生—诊断学]