摘要
目的 分析我国对碳青霉烯类药物敏感性降低肠杆菌科细菌中碳青霉烯酶基因的携带情况及分子流行病学特征.方法 收集全国1 1个城市14家医院临床分离的碳青霉烯类药物不敏感肠杆菌科细菌201株,采用琼脂稀释法检测14种抗菌药物的MICs,改良Hodge试验和乙二胺四乙酸（EDTA）协同试验筛检碳青霉烯酶表型,PCR扩增测序确证菌株携带的耐药基因.对产碳青霉烯酶菌株进行接合试验,脉冲场凝胶电泳（PFGE）和多位点序列分型（MLST）分析.结果 201株碳青霉烯类药物敏感性降低肠杆菌科细菌中有53株确定为产碳青霉烯酶[KPC-2（32株）、IMP-4（20株）、IMP-8（1株）],其中肺炎克雷伯菌33株、弗劳地枸橼酸杆菌9株、大肠埃希菌6株、阴沟肠杆菌5株,分别来自于北京（43株）、杭州（6株）、南京（3株）、福州（1株）4个地区;将53株产酶菌株与大肠埃希菌EC600进行接合,获得28株接合子;PFGE分型结果显示,肺炎克雷伯菌（33株）可分为3个型2个亚型、弗劳地枸橼酸杆菌（9株）可分为4个型、阴沟肠杆菌（5株）可分为4个型、大肠埃希菌（6株）均为同一型;29株产KPC-2型酶肺炎克雷伯菌的MLST分型序列均为ST11,4株产IMP-4型酶肺炎克雷伯菌中3株为ST876,1株为ST147.结论 在对我国11个城市的耐药菌监测中只有北京、杭州、南京和福州的医院中检出携带碳青霉烯酶基因的菌株,其中KPC-2最常见,其次为IMP-4、IMP-8,菌株间同源性较高,由于碳青霉烯酶基因在菌株问容易发生水平转移,应引起临床高度关注.
Objective To analyze the genotype and molecular epidemiology of carbapenem-resistant Enterobacteriaceae.Method A total of 201 carbapenem-resistant Enterobacteriaceae were isolated from 14hospitals in 11 cities.The MICs of 14 antimicrobial drugs were detected using agar dilution method.Phenotypes of carbapenemases were screened using modified Hodge test and ethylene diamine tetraacetic acid （EDTA） test.Drug resistance genes were screened using PCR method.The strains carrying carbapenem resistance genes were confirmed by conjugation test.Homology analysis was carried out using pulsed-field gel electro-phoresis （PFGE） method and the epidemiological correlation is analyzed based on the Multilocus Sequence Typing （MLST） method in order to study the molecular epidemiology of carbapenem-resistant Enterobacteriaceae.Results Fifty-three strains among 201 carbapenem-insensitive Enterobacteriaceae were detected positive carbapenem-resistant genes,among which included 33 Klebsiella pneumoniae,9 Citrobacter freundii,6 Escherichia coli and 5 Enterobacter cloacae.Among the 53 strains,43 were from Beijing,6 strains from Hangzhou,3 strains from Nanjing and one from Fuzhou.Resistance genes-harboring plasmids were successfully transferred from 28 of 53 strains to Escherichia coli EC600.The PFGE spectmm showed that 33 Klebsiella pneumoniae were classified into three types,9 Citrobacterfreundii classified into four types,5 Enterobacter cloacae classified into four types,while 6 Escherichia coli were the same type.Based on the results of MLST test,29 Klebsiella pneumoniae strains producing KPC-2 type carbapenemase were all ST11,while among the four Klebsiella pneumonia carrying IMP-4 carbapenem resistant gene,three strains were ST876,one was ST147.Conclusions Carbapenem-resistant genes were detected only in hospitals from Beijing,Hangzhou,Nanjing and Fuzhou,and type KPC-2 was the most common,followed by IMP-4 and IMP-8.High homology of resistant strains could be related to horizontal transfer of carbapenemase genes,which s
出处
《中华内科杂志》
CAS
CSCD
北大核心
2014年第2期116-120,共5页
Chinese Journal of Internal Medicine
基金
北京市教委重点项目（KZ201210025025）
教育部新世纪人才支持计划（NCET-10-0205）
教育部高等学校博士学科点专项科研基金（20110001110043）
北京大学985-3期工程临床医院合作专项
关键词
肠杆菌科
碳青霉烯酶
基因型
Enterobacteriaceae
Carbapenemase
Genotype
