医院分离多重耐药鲍曼不动杆菌耐药基因的研究

目的研究多重耐药鲍曼不动杆菌(MDR-Ab)的耐药性及相关耐药基因,为临床抗菌药物的合理选择提供依据。方法采用MicroScan WalkAway96全自动微生物鉴定/药敏测试系统筛选鲍曼不动杆菌(Ab)98株;采用聚合酶链式反应检测MDR-Ab携带相关耐药基因OXA-23、OXA-24、IMP、VIM、TEM、SHV;并对耐药基因扩增阳性的产物进行DNA序列分析。结果 98株MDR-Ab对青霉素类和头孢类抗菌药物的耐药率均为100.0%;对氨苄西林/舒巴坦的耐药率为73.5%,对亚胺培南和美罗培南的耐药率分别为55.1%和54.1%,对庆大霉素、阿米卡星、妥布霉素的耐药率分别为100.0%、100.0%和87.8%,对环丙沙星、左氧氟沙星、加替沙星的耐药率分别为89.8%、91.8%和77.6%,对磺胺甲噁唑和利福平的耐药率分别为91.8%和100.0%,对多黏菌素和多黏菌素B的耐药率分别为14.3%和11.2%,对四环素、米诺环素、替加环素的耐药率分别为100.0%、6.1%、4.1%;98株MDR-Ab耐药基因检测,各有70株携带OXA-23和TEM基因,53株携带VIM基因,41株携带IMP基因,未检测到OXA-24、SHV基因;DNA序列分析结果显示OXA-23、TEM、IMP和VIM 4种基因分别与NCBI序列的同源性为98%、98%、99%和99%。结论该地区临床分离MDR-Ab耐药情况比较严重,耐药基因的携带以OXA-23和TEM为主,携带多种耐药基因是导致MDR-Ab耐药的重要原因,临床医务人员对Ab感染患者应尽量根据药敏试验结果合理使用抗菌药物。

Study on multiple drug resistance gene of Acinetobacter baumanii isolated from hospital

Objective To study the drug resistance of multiple‐drug‐resistant Acinetobacter baumannii(MDR‐Ab) and its rela‐tive carbapenemases genes ,in order to provide references for rational use of antibacterial agents .Methods A total of 98 strains of Acinetobacter baumannii(Ab) were identified by using the MicroScan WalkAway96 automated microbial identification susceptibility testing system ,and the resistance genes ,including OXA‐23 ,OXA‐24 ,IMP ,VIM ,TEM and SHV ,were detected by using the poly‐merase chain reaction .DNA sequences of positive amplification products of the resistance gene were analysed .Results The drug re‐sistance rates of 98 strains of MDR‐Ab to penicillin class and cephalosporin class both were 100 .0% ,to imipenem and meropenem were 55 .1% and 54 .1% respectively ,to gentamicin ,amikacin and tobramycin were 100 .0% ,100 .0% and 87 .8% respectively ,to ciprofloxacin ,levofloxacin and gatifloxacin were 89 .8% ,91 .8% and 77 .6% respectively ,to sulfamethoxazole and rifampicin were 91 .8% and 100 .0% respectively ,to polymyxin B and polymyxin were 14 .3% and 11 .2% respectively ,to tetracycline ,minocycline and tigecycline were 100 .0% ,6 .1% and 4 .1% respectively .The results of resistance genes detection in 98 strains of MDR‐Ab showed that 70 strains carried TEM and OXA‐23 gene ,53 strains carried VIM gene ,41 strains carried IMP gene ,while OXA‐24 and SHV genes were not detected .DNA sequence analysis showed that the homology of OXA‐23 ,TEM ,IMP and VIM genes were 98% ,98% ,99% and 99% .Conclusion The condition of antibacterial resistance of MDR‐Ab in this area is very serious ,and TEM and OXA‐23 are the main drug resistance genes .Carrying multiple resistance genes is an important cause of MDR‐Ab resistance . The treatment of patients with Ab infection should be based on the results of drug sensitivity test for rational use of antibacterial a‐gents .