多重耐药鲍曼不动杆菌中16SrRNA甲基化酶基因的检测及耐药分析

Detection of 16SrRNA methylase gene in multiple drug resistant Acinetobacter baumannii and associated antibiotic resistance

目的了解医院分离的多重耐药鲍曼不动杆菌16SrRNA甲基化酶基因分布情况,为临床合理应用抗菌药物提供依据。方法采用Phoenix100微生物全自动鉴定系统进行菌株鉴定及药敏试验;采用PCR方法检测armA、rmtA、rmtB、rmtC、rmtD基因。结果 46株鲍曼不动杆菌中armA基因阳性36株,阳性率78.3%,未检出rmtA、rmtB、rmtC、rmtD基因。药敏试验结果显示医院分离的多重耐药鲍曼不动杆菌对多黏菌素全部敏感,对四环素、阿米卡星、庆大霉素、妥布霉素、甲氧苄啶-磺胺甲唑耐药率分别为13.0%、80.4%、91.3%、95.7%、95.7%,对其他测试药物耐药率100%。结论医院分离鲍曼不动杆菌对氨基糖苷类抗菌药物耐药性已非常严重,携带armA基因是导致氨基糖苷类耐药的原因之一,延缓鲍曼不动杆菌多重耐药性已刻不容缓。

Objective To investigate the prevalence of 16SrRNA methylase gene in the strains of multidrug-resistant A cinetobacter baumannii isolated from patients to provide basis for rational use of antimicrobial agents. Methods Phoenix 100 automated microbial identification system was used for strain identification and antimicrobial susceptibility testing. PCR was used for detection of armA, rmtA, rmtB, rmtC, and rmtD genes. Results The armA gene was positive in 36 （78.3 %） of the 46 strains. All the strains were negative for rmtB, rmtA, rmtC, and rmtD genes. Susceptibility testing showed that the multi-drug resistant A. baumannii strains were susceptible to polymyxin, but various resistance rates to tetracycline （13.0%）, amikacin （80.4%）, gentamicin （91.3 %）,tobramycin （95.7 %）, and trimethoprim-sulfamethoxazole （95.7 %）, and 100 % resistant to the other antimicrobial agents tested. Conclusions The antibiotic resistance is very serious in Acinetobacter baumannii, especially those carrying armA gene, which confers aminoglycoside resistance. We have no time to waste in containing the multidrug-resistance ofAcinetobacter baumannii.