江苏省溧阳地区耐碳青霉烯类肺炎克雷伯菌耐药元件及亲缘关系研究

Investigation of resistant genes and relationship in carbapenems-resistant Klebsiella pneumoniae of Liyang,Jiangsu Province

目的了解医院耐碳青霉烯类肺炎克雷伯菌(CRKP)常见耐药原件的携带及亲缘关系。方法收集2014年1月-2016年1月在院患者中分离20株CRKP,采用PCR分析了40种β-内酰胺类酶基因与11种可移动遗传元件(MGEs)标记基因检测,并同步检测了20种氨基糖苷类药物获得性耐药基因。且进一步对检测结果作样本聚类分析,了解其亲缘关系。结果 20株CRKP对β-内酰胺类药物(亚胺培南、美罗培南、头孢噻肟、头孢他啶、头孢吡肟、氨苄西林/舒巴坦、哌拉西林/他唑巴坦)、氨基糖苷类药物(庆大霉素、阿米卡星)、喹诺酮类药物(诺氟沙星、环丙沙星、左氧氟沙星)等12种抗菌药物均耐药;20株CRKP均检出blaTEM与blaKPCβ-内酰胺酶基因;氨基糖苷类药物获得性耐药基因每株也均有检出,但不同基因阳性率不同;MGEs每株也均有检出,但intⅠ1与IS903阳性率不同;样本聚类分析提示,20株CRKP呈明显的聚集现象(A群),并可分为A-A群与A-B群。结论医院CRKP部分存在同源性,主要流行基因型为blaTEM与blaKPC,流行MGEs遗传标记为trbC、ISEcp1、IS26与ISKpn6,需要加强医院感染管理。

OBJECTIVE To investigate the prevalence and relationship of common resistant genes to carbapenem-resistant Klebsiella pneumoniae（CRKP）in our hospital.METHODS Twenty strains of CRKP isolated from our hospital from Jan.2014 to Jan.2016 were collected and analyzed by PCR for the detection of 40β-lactamase genes and11 markers of mobile genetic elements（MGEs）,and 20 kinds of aminoglycoside-acquired drug resistant genes were detected simultaneously.The results were analyzed by cluster analysis to find out their genetic relationship.RESULTS Twenty strains of CRKP were found to be resistant toβ-lactam drugs（imipenem,meropenem,cefotaxime,cefepime,cefepime,ampicillin/sulbactam,piperacillin/tazobactam）,aminoglycoside drugs（gentamicin,amikacin）,and quinolones（norfloxacin,ciprofloxacin,levofloxacin）.BlaTEM and blaKPCβ-lactamase genes were detected in 20 strains of CRKP,and aminoglycoside drug-resistant genes were also detected in each strain,but different genes had different positive rates.MGEs were also detected in each strain,but the positive rates of intⅠ1and IS903 were different.The cluster analysis showed that 20 strains of CRKP showed obvious aggregation（group A）and could be divided into A-A group and A-B group.CONCLUSIONThere are some homologies between CRKP strains in our hospital.The major prevalent genotypes are blaTEM and blaKPC.The prevalent markers of MGEs are trbC,ISEcp1,IS26,and ISKpn6,and it needs to strengthen hospital infection management.