耐药肺炎克雷伯菌β-内酰胺酶编码基因及KPC-ISKpn6连锁检测  

Detection ofβ-lactamases encoding genes and KPC-ISKpn6in drug-resistant Klebsiella pneumoniae

作　　者：毛彩萍[1] 樊璠[1] 叶珍[1] 尤佳女[2] 奚伟星[3] 边佳[1] 糜祖煌[4] 陈文虎[1] 

机构地区：[1]浙江省肿瘤医院检验科,浙江杭州310022 [2]浙江省新华医院检验科,浙江杭州310006 [3]浙江省立同德医院检验科,浙江杭州310014 [4]无锡市克隆遗传技术研究所生物信息学室,江苏无锡214026

出　　处：《中华医院感染学杂志》2014年第18期4424-4426,共3页Chinese Journal of Nosocomiology

基　　金：浙江省医药卫生科技基金资助项目(2012KYA026)

摘　　要：目的研究和分析18株耐药肺炎克雷伯菌产β-内酰胺酶基因表达及KPC型阳性菌株与插入序列ISKpn6的关联。方法采用微生物鉴定仪鉴定并通过gyrA、parC基因测序和比对确认了18株肺炎克雷伯菌,对抗菌药物的药敏试验采用K-B纸片扩散法;40种β-内酰胺酶基因和KPC型β-内酰胺酶编码基因与插入序列(KPCISKpn6)连锁检测均采用PCR法,β-内酰胺酶编码基因的亚型通过测序和比对进行确认。结果 18株耐药肺炎克雷伯菌除对四环素、米诺环素的敏感率>83.3%外,对其余抗菌药物的敏感率均<50.0%,有的甚至100.0%耐药;40种β-内酰胺酶基因中共检出TEM-1 17株、CTX-M-3 4株、LAP-2 1株、KPC-2 14株、IMP-4 2株、DHA-1 4株、OXA-1 1株共7种耐药基因亚型,且基因检出与其细菌耐药表型相符合;14株KPC-2型阳性菌株KPC-ISKpn6连锁检测均为阳性。结论耐药肺炎克雷伯菌每一株均有阳性基因检出,且检出的7种耐药基因亚型分布于β-内酰胺酶4个类别中,显示耐药株携带的β-内酰胺酶编码基因多种性;14株携带KPC-2型基因的阳性株其KPC-ISKpn6连锁检测均为阳性,提示KPC-2型β-内酰胺酶编码基因与插入序列ISKpn6高度关联。OBJECTIVE To investigate the expression of β-lactamase genes in 18 strains of drug-resistant K lebsiella pneumoniae and study the correlation between KPC-positive strains and insertion sequence ISKpn6 .METHODS Totally 18 strains of K .pneumoniae have been identified through the microorganism identification system and the gyrA and parC gene sequencing ,then the drug susceptibility testing was performed by using K-B disk diffusion method ,the detection of 40β-lactamase genes ,KPC-typeβ-lactamase encoding genes and insertion sequence（KPC-ISKpn6） were performed by using PCR ,and the subtypes of the β-lactamases encoding genes were confirmed through sequencing and comparison .RESULTS Among the tested antibiotics ,the drug susceptibility rates of the 18 strains of K .pneumoniae to tetracycline and minocycline were more than 83 .3% ,the drug susceptibility rates to other antibiotics were less than 50 .0% ,and the drug resistance rates to some antibiotics were even as high as 100 .0% .Totally 7 subtypes of drug resistance genes were detected among the 40 β-lactamase genes ,including TEM-1 in 17 strains ,CTX-M-3 in 4 strains ,LAP-2 in 1 strain ,KPC-2 in 14 strains ,IMP-4 in 2 strains ,DHA-1 in 4 strains ,and OXA-1 in 1 strain;the detection of theβ-lactamase coding genes was consistent with the pheno-type of bacterial drug resistance ;the detection of KPC-ISKpn6 of all the 14 KPC-2-positive strains was positive . CONCLUSION The gene is detected positive in each strain of this group of drug-resistant K .pneumoniae ,the 7 de-tected subtypes distribute in four types of β-lactamases ,indicating that the β-lactamases encoding genes in the＆amp;nbsp;drug-resistant strains are diversified ;the chain detection of KPC-ISKpn6 of all the 14 KPC-2-positive strains is positive ,indicating that the KPC-2-typeβ-lactamases encoding gene is highly correlated with the insertion sequence ISKpn6 .

关 键 词：肺炎克雷伯菌 耐药基因 插入序列 

分 类 号：R378.996[医药卫生—病原生物学]