目的探讨耐碳青霉烯类肺炎克雷伯菌耐药基因及可移动遗传元件遗传标记的携带,与菌株间的亲缘性。方法收集2014年1-12月住院患者中分离20株耐碳青霉烯类肺炎克雷伯菌,经gyrA测序比对确认菌种,再采用聚合酶链反应(PCR)及序列分析的方法分析β-内酰胺类、氨基糖苷类、喹诺酮类共57种耐药相关基因与12种可移动遗传元件遗传标记,最后对检测结果作样本聚类分析。结果 20株耐碳青霉烯类肺炎克雷伯菌每株均检出β-内酰胺酶基因、氨基糖苷类修饰酶基因、喹诺酮类作用靶位基因gyrA突变以及可移动遗传元件标记;20株菌共检出4种β-内酰胺类耐药基因、4种氨基糖苷类耐药基因、1种16SrRNA甲基化酶基因、1种喹诺酮类耐药基因、6种可移动遗传元件遗传标记,阳性率非常高,且阳性基因可分为6种阳性模式;样本聚类分析发现,20株菌可区分为A、B两个家族,A家族中1号株为孤独株,A1(2和9号株)与A2(10、11、12、13、15、16、17和18号株)子家族均为克隆传播,A3子家族有2株菌;B家族(3、4、5、6、7、8和20号株)亦为克隆传播,并已构成暴发流行。结论本组肺炎克雷伯菌中携带的耐药基因与耐药表表型相对应,样本聚类分析提示本组菌有克隆传播,有的已构成暴发流行。
OBJECTIVE To investigate the distribution status of resistant genes and genetic markers of mobile genetic elements in carbapenem-resistant Klebsiella pneumonia(CRKP)and affinity among strain groups.METHODS From Jan.to Dec.2012,20 strains of CRKP were isolated from the inpatients,then the identification of strains was performed by gyrA.Then,57 kinds of resistant genes to beta-lactams,aminoglycosides,quinolones,and 12 kinds of genetic markers of mobile genetic elements were analyzed by PCR.Finally,sample cluster analysis was performed on these genes.RESULTS Beta-lactamases,aminoglycosides modifying enzymes,mutation of quinolones target gene gyrA,and genetic markers of mobile genetic elements were positive in every strain.In the 20 strains,4kinds of beta-lactamase genes,4kinds of aminoglycosides modifying enzyme genes,one kind of16 SrRNA methylase gene,one kind of resistant gene to quinolone,and 6kinds of genetic markers of mobile genetic elements were positive,and positive rates were very high.In addition,6kinds of positive modes were divided.Sample cluster analysis showed that the 20 strains can be divided into cluster A and B.Strain No.1was an isolated strain,cluster A1(Strain No.2and 9)as well as A2(Strain No.10,11,12,13,15,16,17,18)were clonal transmitted,while cluster A3 included 2strains.Cluster B(Strain No.3,4,5,6,7,8and 20)were clonal transmitted.CONCLUSIONResistant genes and phenotypes in this group of CRKP were identical.Sample cluster analysis showed that clonal transmission existed.