氨曲南联合头孢他啶/阿维巴坦对产金属β-内酰胺酶肠杆菌目细菌的体外协同作用初探

摘要：目的 探讨氨曲南(aztreonam，ATM)与头孢他啶/阿维巴坦(ceftazidime averbatan，CAZ/AVI)联合使用对产金属β-内 酰胺酶(metallo-β-lactamases, MBLs)肠杆菌目细菌的体外协同作用。方法 收集四川大学华西医院2019年11月—2020年4月临床 分离的32株产MBLs且同时满足对ATM及CAZ/AVI耐药；采用PCR扩增技术进行基因型检测，采用微量肉汤稀释法测定ATM及 CAZ/AVI的MIC及棋盘稀释法检测ATM联合CAZ/AVI对产MBLs的肠杆菌目细菌的协同作用。结果 32株产MBLs的菌株中，产 NDM-1型金属酶19株，产NDM-5型金属酶12株及产IMP型金属酶1株；ATM联合CAZ/AVI对其中26株产MBLs的菌株有体外协 同作用，占比81.3%；未出现无关和拮抗作用。结论 ATM联合CAZ/AVI对产NDM金属酶菌株体外有协同抗菌作用的可能性较 高，因此有条件情况下，如果临床治疗需要最好做联合药敏试验以更好的指导临床用药。

In vitro synergistic activity of aztreonam combined with ceftazidime/avibactam on metallo-β-lactamases-producing Enterobacteriaceae bacteria

Abstract Objective To investigate the in vitro synergistic activity of aztreonam (ATM) and ceftazidime/ avibactam(CAZ/AVI) on metal-β-lactamases-producing(MBLs)Enterobacteriaceae bacteria. Methods 32 metallo- β-lactamases-producing strains were isolated from West China Hospital, Sichuan University from November 2019 to April 2020 which were resistant to aztreonam and ceftazidime/avibactam were collected, the genes were analyzed by polymerase chain reaction, the minimum inhibitory concentration of aztreonam and ceftazidime/avibactam were determined by using micro broth dilution method and the synergistic activity of ATM combined with CAZ/AVI on metallo-β-lactamases-producing. Enterobacteriaceae were determined by using checkerboard dilution. Results Among the 32 strains of MBLs-producing, 19 strains coproducing NDM-1, 12 strains coproducing NDM-5 and 1 IMP were identifed; ATM and CAZ/AVI has synergistic activity on the MBLs of 26 plants, which is 81.3%. There was no correlation and antagonism.Conclusion ATM combined with CAZ/AVI is more likely to have synergistic antibacterial effect on NDM metalloenzyme producing strains in vitro, therefore, clinical treatment needs to do combined drug sensitivity test to better guide clinical medication.