碳青霉烯耐药肺炎克雷伯菌医院暴发流行的耐药机制及同源性研究  

Drug resistance mechanisms and homology of carbapenem-resistant Klebsiella pneumoniae prevalent in hospitals

作　　者：张海峰[1] 姚静[2] 杜兴冉[2] 张扬[2] 高天明[1] 翁晓芹 冯旰珠[2] 

机构地区：[1]南京医科大学第二附属医院东院急诊科,江苏南京210000 [2]南京医科大学第二附属医院呼吸科,江苏南京210011

出　　处：《中华医院感染学杂志》2016年第22期5041-5045,共5页Chinese Journal of Nosocomiology

基　　金：国家自然科学基金(81470209);江苏省"六大高峰人才"项目资助(WSN-206-123)

摘　　要：目的 研究临床分离耐碳青霉烯类肺炎克雷伯菌（CRKP）时间分布规律、耐药机制及菌株同源性,为预防控制医院感染提供依据。方法 自2011年1月分离出第1株CRKP后,对随后分离的所有CRKP实时监控;检测各分离株的主要耐药基因、膜孔蛋白基因突变及插入序列ISKpn6表达状况;对暴发流行期间分离的22株CRKP分别用凝胶电泳（PFGE）及多位点序列分型（MLST）法探讨其菌株同源性。结果 2011年1月-2013年12月共分离38株CRKP,其中2011年分离率为13.2%;2012年上半年分离率为57.9%,呈暴发流行;2012年下半年及2013年全年分离率分别为18.4%及10.5%。38株菌株皆产KPC-2酶,TEM-1、SHV的携带率及插入序列ISKpn6阳性率均为100%;DHA-1及LAP-2阳性率分别为47.4%及50%;膜孔蛋白编码基因OmpK35及OmpK36的突变率分别为94.7%及100%。PFGE显示,暴发流行期间22株CRKP分属A1-E 7个克隆,其同源性达75%以上;MLST显示,22株菌株的优势型为ST11及ST258,各占31.8%。结论 本次暴发流行CRKP同时存在多种耐药机制,以ST11及ST258型为主,加强综合预防控制措施能有效遏制该菌株传播流行。OBJECTIVE To explore the temporal distribution rules ,drug resistance mechanisms ,and homology of clinical carbapenem‐resistant K lebsiella pneumoniae isolates so as to provide guidance for prevention and control of nosocomial infections .METHODS Since the first strain of carbapenem‐resistant K .pneumoniae was isolated in Jan , 2011 ,the real‐time monitoring was carried out for all of the following isolated carbapenem‐resistant K .pneumoni‐ae strains ;the major drug resistance genes ,membrane porin gene mutation ,and expression of insertion sequence ISKpn6 were detected;the homology of the 22 strains of carbapenem‐resistant K .pneumoniae that were isolated during the epidemic period was explored using pulsed‐field gel electrophoresis （PFGE） and multilocus sequence typing （MLST） .RESULTS A total of 38 strains of carbapenem‐resistant K .pneumoniae were isolated from Jan 2011 to Dec 2013 ;the isolation rate was 13 .2% in 2011 ;the isolation rate was 57 .9% in first half year of 2012 , showing outbreak and prevalence;the isolation rate was 18 .4% in the second half year of 2012 ,10 .5% in 2013 . All of the 38 strains produced KPC‐2 enzyme;the carrying rates of TEM‐1 and SHV and the positive rate of inser‐tion sequence ISKpn6 were 100% .The positive rates of DHA‐1 and LAP‐2 were 47 .4% and 50% ,respectively ;the mutation rates of membrane porin genes OmpK35 and OmpK36 were 94 .7% and 100% ,respectively .The PFGE showed that the 22 strains of carbapenem‐resistant K .pneumoniae that were isolated during the epidemic period belonged to A1 ,A2 ,B1 ,B2 ,C ,D1 ,D2 and E7 clone ,with the affinity more than 75% .The MLST indicated that the ST11 and ST258 were the predominant types of the 22 strains ,accounting for 31 .8% and 31 . 8% ,respectively .CONCLUSION There are a variety of drug resistance mechanisms in the carbapenem‐resistant K .pneumoniae strains;the ST11 and ST258 are the predominant types .It is an effective way to strengthen the comprehensive prevention and control measures s

关 键 词：肺炎克雷伯菌 碳青霉烯耐药 耐药机制 同源性 医院感染 暴发流行 

分 类 号：R378.996[医药卫生—病原生物学]