ICU病区泛耐药的鲍曼不动杆菌碳青霉烯类药物耐药基因分析

Analysis of The Carbapenems Resistant Genes in the Pandrug-Resistant Acinetobacter Baumannii from ICU Wards

目的研究ICU区病区分离的泛耐药(pandrug-resistant,PDR)鲍曼不动杆菌的耐药机制,检测菌株所含的主要基因型别及其流行情况,指导临床合理用药。方法收集2009～2010年两年分离自ICU病区的PDR鲍曼不动杆菌20株,用浓度梯度法(E-试条法)检测15种抗菌药物的耐药率,用PCR法检测blaOXA-23、blaOXA-24、blaOXA-51、blaOXA-58、blaVIM、blaNDM-1和blaIMP 7种基因型别。结果 20株PDR鲍曼不动杆菌,对常规的14种抗菌药物耐药率阿米卡星55%,米诺环素70%,复方新诺明80%,其他药物均100%;对多黏菌素B的耐药率为0;PCR检测结果显示,检测到3种耐药基因,blaOXA-23、blaVIM和blaIMP;其中14株细菌blaOXA-23阳性,2株blaVIM阳性,1株blaIMP阳性,总阳性率85.5%。结论 PDR-AB对绝大多数常规药物均有较高的耐药性,其耐药机制复杂,对碳青霉烯类耐药的耐药基因主要为blaOXA-23,亟待我们积极深入地探索研究。

Objective To investigate the carbapenems resistant gcnotypes of pandrug - resistance of ICU wards isolates of Acineto- bacter baumannii in order to provide a scientific basis for the rational use of antibiotics. Methods Totally 20 strains of pandrug - resistant Acinetobacter baumannii were collected and the minimum inhibition concentration was tested with E - test method. The carbapenems resist- ant genotypes of blaOXA- 23 ,blaOXA- 24, blaOXA -51, blaOXA -58, blaVIM, blaNDM -1 and blaIMP were performed by PCR meth- od. Results The resistance rates of 20 strains of Acinetobacter baumannii to piperacillin, piperacillin - tazobactam, cefotaxime, ceftazi- dime, ceftriaxone, cefepime,cefoperazone - sulbactam,imipenam, meropenem, gentamycin and ciprofloxaein were all 100% , but to ami- kacin 55% ,to minocycline 70% ,to trimethoprim - sulfame tboxazole 80% and to polymyxin B 0.0% . PCR experiment showed that 14 strains with blaOXA - 23 and 2 strains with blaVIM and one strain with blaIMP were positive. Conclusion The pandrug - resistant Acine- tobacter baumannii was seized of higher drug - resistance rates. The main cause of carbapenems resistance of pandrug resistant Acinetobact- er baumannii was producing β - lactams such as carbapenemase. The main genotypes were blaOXA - 23 and blaVIM. More steps should be taken to control the spread of these resistance isolates.