检测多药耐药鲍氏不动杆菌的碳青酶烯酶及整合酶基因

Genes of Carbapenemases and Integrases in Multi-drug Resistant Acinetobacter baumannii

目的检测多药耐药鲍氏不动杆菌(MDRAba)的碳青酶烯酶及整合酶基因。方法从70株对耐亚胺培南鲍氏不动杆菌中用PCR方法测定碳青酶烯酶OXA23类、OXA24类、OXA51类和OXA58类基因及Ⅰ类和Ⅱ类整合酶基因,对扩增阳性的碳青酶烯酶基因进行测序分析;抗菌药物敏感试验采用琼脂稀释法。结果获得OXA-23类基因阳性56株,占80.0%,OXA-58类基因阳性1株,仅1株菌OXA51类基因阴性;Ⅰ类整合酶基因阳性61株,占87.1%,未测得OXA24类碳青酶烯酶和Ⅱ类整合酶基因;序列分析提示分离的CRAba为OXA-23型和OXA-58型,所测菌株对环丙沙星、头孢他啶、庆大霉素、哌拉西林/他唑巴坦高度耐药,对多黏菌素B一致性敏感。结论新近出现的CRAba菌株主要是以Ⅰ类整合子携带的OXA-23型碳青酶烯酶。

OBJECTIVE To investigate the genes of carbapenemases and integrases in multi-drug resistant Acineto- bacter baurnannil （MDRAba）, METHODS PCR was used for detection of genes of carbapenemases： OXA-23-like, OXA-24-like, OXA-51-like, and OXA-58-1ike, and integrases Ⅰ and Ⅱ from 70 clinical strains of carbapenemresistant A. baumannil （CRAba）. PCR products of OXA-23-1ike and OXA-58-1ike were analyzed by sequencing. Agar dilution method was carried out for antimicrobial susceptibility test. RESULTS Genes for OXA-23-like and OXA-51-like were positive from 56 and 69 isolates, accounted for 80. 0% and 98. 6%, respectively; gene of OXA- 58-like was detected from only one strain. Sixty one strains showed positive for integrase Ⅰ gene. OXA-23 or OXA-58 was the exact gene type by sequencing. All 70 strains were highly resistant to ciprofloxacin, ceftazidime, and gentamicin, but susceptible to polymyxin B. CONCLUSIONS CRAba strains distributed in General Hospital of PLA mainly possess OXA-23 type carbapenemase and integrase Ⅰ .