高龄住院患者鲍曼不动杆菌多重耐药相关基因的监测

目的 了解老年病区鲍曼不动杆菌临床分离株携带多重耐药相关基因的情况,为耐药性监测及感染控制提供依据.方法 筛选解放军总医院2008-2010年自临床分离的120株不重复鲍曼不动杆菌,患者平均年龄85(65～95)岁.使用Whonet 5.6软件分析其对16种抗菌药物的耐药率；应用聚合酶链反应及测序方法检测10种耐药相关基因(blaOXA-51-like、blaOXA-23-like、blaOXA--24-like、blaOXA-58-like、blaTEM、blaampC、armA、ISAba1、intI1和intI2),依据耐药基因的检出情况,分析并命名相应的耐药基因谱(RGP).结果 上述120株鲍曼不动杆菌除了对多黏菌素B的敏感率超过90％以外,对其他15种抗生素均具有较高的耐药率(70.8％～97.5％)；耐药相关基因blaOXA-51-like、blaOXA-23-like、blaOXA-58-like、blaTEM、blaampC、armA、ISAba1和intI1的阳性率分别为100％、81.7％、0.8％、10.8％、91.7％、81.7％、86.7％和83.3％,未检出blaOXA-24-like和intI2；共发现18种耐药基因谱,其中多重耐药谱RGP1(blaOXA-23-like+blaampC+armA+ISAba1+intI1)所占的比例高达60.8％.结论 老年住院患者中分离的鲍曼不动杆菌多重耐药相关基因携带率较高,多重耐药现象非常严重；应积极、有效、合理地防控和治疗老年住院患者鲍曼不动杆菌感染,医院感染管理专职人员与临床医师对此应予以高度重视.

Surveillance of multidrug-resistant genes in Acinetobacter baumannii isolates from elderly patients

Objective To investigate the status of multidrug-resistant genes carried by Acinetobacter baumannii isolates from elderly patients in our hospital in order to provide a basis for surveillance of drug-resistance and inflection control.Methods One hundred and twenty A.baumannii isolates were collected from elderly patients between 2008 and 2010.The mean age of the patients was 85(65 to 95) years.Whonet 5.6 software was used to analyze the susceptibility of 16 antimicrobial agents.Polymerase chain reaction(PCR) and the sequencing method were adopted to detect 10 kinds of resistance genes(blaOXA-51-like,blaOXA-23-like,blaOXA-24-like,blaOXA-58-like,blaTEM,blaampC,armA,ISAba1,intI 1,and intI 2).The corresponding resistance gene profiling(RGP) was analyzed and designated according to the status of resistance genes.Results The rates of resistance to the remaining 15 kinds of antibiotics varied between 70.8% and 97.5%,with the exception of the sensitive rate to polymyxin B by up to more than 90%.The positive rates of blaOXA-51-like、blaOXA-23-like、blaOXA-58-like、blaTEM、blaampC、armA、ISAba1 and intI 1 were 100%,81.7%,0.8%,10.8%,91.7%,81.7%,86.7%,and 83.3% respectively.A total of 18 kinds of drug-resistant gene maps were found,but blaOXA-24-like and intI 2 were not detected.Among these gene maps,the rate of RGP1(blaOXA-23-like+blaampC+armA+ISAba1+ intI 1) was as high as 60.8%.Conclusions A.baumannii isolates from elderly patients have a higher carrying rate of drug-resistant genes,resulting in serious multidrug-resistant conditions.Therefore,full-time infection control personnel and clinical physicians should actively participate in the surveillance,prevention,and control of infections caused by A.baumannii in the elderly.