耐碳青霉烯类鲍曼不动杆菌耐药基因检测及同源性

 目的 探讨某三甲医院耐碳青霉烯类鲍曼不动杆菌(CRAB)耐药基因携带情况及同源性。方法 收集该院2017年10月—2018年10月共40株CRAB,采用聚合酶链式反应(PCR)检测耐药基因携带情况,同时应用脉冲场凝胶电泳(PFGE)分析其同源性。结果 40株CRAB对大部分抗菌药物耐药率在90%左右,对替加环素的耐药率相对较低,为2.9%(未包括中介)。耐药基因ADC检出率为100%,其他耐药基因检出率较高的依次为OXA-51(36株,90.0%)、qacE△1-sull(32株,80.0%),未检测出KPC基因。每株CRAB菌株检出2~8种耐药基因,以检出6种耐药基因的菌株最多(15株,37.5%);检出的耐药基因组合中,以同时检出ADC+OXA-23+OXA-51基因最多(29株,72.5%),其次为ADC+intl1+qacE△1-sull基因(26株,65.0%)、ADC+qacE△1-sull+ant(3″)-Ⅰ基因(19株,47.5%),11株(27.5%)同时检出ADC+ant(3″)-Ⅰ+aac(3)-Ⅰ基因。PFGE同源性检测分出19种不同型别,每种型别1~9株不等,其中A5型有9株,A18型有8株,主要来自重症监护病房。结论 该院CRAB对临床常见抗菌药物呈高度耐药,OXA-23和OXA-51两种基因最有可能是引起该院鲍曼不动杆菌耐药的主要因素,同源性分析显示该院不同病区存在CRAB医院感染传播。

Detection and homology of drug resistance genes of carbapenem-resistant Acinetobacter baumannii

Objective To evaluate the carrying status and homology of drug resistance genes of carbapenem-resis-tant Acinetobacter baumannii (CRAB) in a tertiary first-class hospital. Methods 40 strains of CRAB were collected from this hospital between October 2017 and October 2018, carrying status of drug resistance genes was detected by polymerase chain reaction (PCR), homology was analyzed by pulsed-field gel electrophoresis (PFGE). Results The resistance rate of 40 strains of CRAB to most antimicrobial agents was about 90%, resistance rate to tigecycline was relatively low (2.9%, intermediate resistance was not included). Detection rate of drug resistance gene ADC was 100%, detection rates of OXA-51 and qacE△1-sull were 90%(n=36 strains) and 80.0%(n=32 strains) respectively, KPC gene was not found. Each CRAB strain was detected 2-8 kinds of resistance genes, and 37.5% of strains (n=15 strains) were detected 6 kinds of resistance genes; among the detected drug resistance gene combinations, 29 strains (72.5%) were simultaneously detected ADC+OXA-23+OXA-51 genes, 26 strains (65.0%) were detected ADC+intl1+qacE△1-sull genes, 19 strains(47.5%) were detected ADC+qacE△1-sull+ant(3″) -Ⅰ genes, 11 strains(27.5%) were detected ADC+ant(3″) -Ⅰ+aac(3) -Ⅰ genes. 19 different types were divided by PFGE homology detection, each type contained 1-9 strains, including 9 strains of type A5 and 8 strains of type A18, mainly from intensive care unit. Conclusion CRAB is highly resistant to common clinical antimicrobial agents, OXA-23 and OXA-51 are most likely to be the main causes of the resistance of AB in this hospital, homology analysis revealed the presence of CRAB HAI in different wards in this hospital.