耐碳青霉烯类鲍氏不动杆菌基因检测与耐药性研究

Genotyping and drug resistance of carbapenem-resistant Acinetobacter baumannii

目的研究耐碳青霉烯类鲍氏不动杆菌基因及其耐药性,为临床治疗与感染控制提供依据。方法收集医院2013年8-11月临床送检标本分离的非重复耐碳青霉烯类鲍氏不动杆菌26株,采用Phoenix100微生物全自动鉴定系统进行菌株鉴定及药敏试验;PCR方法扩增菌株的碳青霉烯酶B类和D类基因;阳性产物经ABI基因测序仪测序确认。结果 26株耐碳青霉烯类鲍氏不动杆菌对多黏菌素无耐药株,对四环素、阿米卡星、庆大霉素、磺胺甲噁唑/甲氧苄啶耐药率分别为11.5%、73.1%、92.4%、96.2%,对其余11种抗菌药物耐药率均为100.0%;26株鲍氏不动杆菌中检出blaOXA-64、blaOXA-51和blaOXA-23阳性率100.0%;blaIMP-1基因阳性率69.2%,未检出blaOXA-24、blaOXA-48、blaOXA-55、blaOXA-58、blaOXA-60、blaOXA-66、blaVIM-2和blaVIM-7基因。结论医院耐碳青霉烯类鲍氏不动杆菌主要碳青霉烯酶基因是blaOXA-23、blaOXA-51、blaOXA-64及blaIMP-1;blaOXA-64、blaIMP-1耐药基因共存同一菌株,是医院耐碳青霉烯类鲍氏不动杆菌的特点,与其他地区不同,医院鲍氏不动杆菌已呈现多药耐药应引起临床重视。

OBJECTIVE To explore the genotypes of the carbapenem‐resistant Acinetobacter baumannii and analyze the drug resistance so as to provide guidance for clinical control and treatment of infection .METHODS A total of 26 strains of non‐repetitive carbapenem‐resistant A .baumannii were isolated from the submitted clinical specimens that were collected from Aug 2013 to Nov 2013 ,then the bacterial identification was carried out by using Phoe‐nix100 microorganism automatic identification system ,the drug susceptibility testing was performed ,the group B and D carbapenemase genes of the strains were amplified with the use of PCR method ,and the positive products were sequenced and confirmed through ABI sequencing instrument .RESULTS Of 26 strains of carbapenem‐resist‐ant A .baumannii ,no strain was resistant to polymycin ,the drug resistance rates to tetracycline ,amikacin ,genta‐micin ,and sulfamethoxazole‐trimethoprim were 11 .5% ,73 .1% ,92 .4% ,and 96 .2% ,respectively ,and the drug resistance rates to the rest of 11 antibiotics were 100 .0% .The positive rates of detection of blaOXA‐64 ,blaOXA‐51 and blaOXA‐23 were 100 .0% in the 26 strains of A .baumannii;the positive rate of the blaIMP‐1 gene was 69 .2% ;the genotypes that were detected negative were as follows ：blaOXA‐24 , blaOXA‐48 , blaOXA‐55 , blaOXA‐58 ,blaOXA‐60 ,blaOXA‐66 ,blaV IM‐2 ,and blaV IM‐7 .CONCLUSION The main carbapenemase geno‐types of the carbapenem‐resistant A .baumannii include blaOXA‐23 ,blaOXA‐51 ,blaOXA‐64 and blaIMP‐1 .The drug resistance genes of blaOXA‐64 and blaIMP‐1 coexist in the same strain ,which is the characteristic of the clinical carbapenem‐resistant A .baumannii strains and differs from the strains isolated from other regions .It is necessary for the hospital to pay high attention to the multidrug‐resistant A .baumannii strain .