广州市ICU环境中耐碳青霉烯类鲍曼不动杆菌的克隆相关性

目的了解广州市重症监护病房(ICU)环境中耐碳青霉烯类鲍曼不动杆菌(CRAB)的克隆相关性,明确其基因分型,为预防和控制医院感染提供依据。方法收集广州市7所医院ICU环境中分离的39株CRAB,采用K-B法测定其对10种抗菌药物的敏感性,采用聚合酶链反应(PCR)检测菌株的OXA基因,采用脉冲场凝胶电泳(PFGE)和多位点序列分型(MLST)对CRAB菌株进行克隆多态性分析。结果 39株CRAB对左氧氟沙星耐药率最低,为56.4%,对其余9种抗菌药物耐药率均90%。PCR扩增结果显示,39株(100%)CRAB均携带OXA-51基因,37株(94.9%)携带OXA-23基因,OXA-24和OXA-58基因未检出。PFGE技术显示,其中38株CRAB分为5个克隆群,A群为主要流行克隆;MLST分析结果显示,CRAB的主要流行克隆型为ST195。结论广州市ICU环境中存在携带OXA-23基因的CRAB克隆传播,应加强ICU环境的清洁和消毒,减少由CRAB引起的医院感染。

Clone correlation of carbapenem resistant Acinetobacter baumannii in environment of intensive care units in Guangzhou City

ObjectiveTo understand the clone correlation of carbapenem resistant Acinetobacter baumannii (CRAB) in the environment of intensive care units(ICUs) in Guangzhou City, identify genotypes, and provide basis for prevention and control of healthcare associated infection(HAI).Methods39 strains of CRAB isolated from environment of ICUs in 7 hospitals in Guangzhou City were collected, susceptibility to 10 kinds of antimicrobial agents was detected by Kirby Bauer method, OXA gene of strains was detected by polymerase chain reaction (PCR), clone polymorphism analysis was performed with pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST).ResultsAmong 39 strains of CRAB, resistance rate to levofloxacin was the lowest(56.4%), resistance rates to other 9 antimicrobial agents were all>90%. PCR results showed that 39 strains(100%) of CRAB all carried OXA 51 gene, 37(94.9%) carried OXA 23 gene, but OXA 24 and OXA 58 genes were not found. PFGE showed that 38 CRAB strains were divided into 5 clones, group A was the main epidemic clone, MLST analysis showed that the main clone of CRAB was ST195.ConclusionTransmission of CRAB clone carrying OXA 23 gene exists in the ICU environment of Guangzhou City, cleaning and disinfection of ICU environment should be intensified, so as to reduce HAI caused by CRAB.