Oie Shigeharu, Fukui Yumi, Yamamoto Masaya, Masuda Yuki, Kamiya Akira
Department of Pharmacy, Yamaguchi University Hospital, Ube, Japan.
BMC Infect Dis. 2009 Aug 10;9:123. doi: 10.1186/1471-2334-9-123.
There are limited choice of antimicrobial agents to treat infection with metallo-beta-lactamase-producing Pseudomonas aeruginosa. We evaluate the antimicrobial effects of aztreonam alone, colistin alone and the 3-drug combination of aztreonam, ceftazidime and amikacin on 23 strains of metallo-beta-lactamase-producing P. aeruginosa by time-killing tests.
Strains used were from different hospitals in Japan and had different pulse-field gel electrophoresis patterns by restriction with SpeI. The minimum inhibitory concentrations of 11 antimicrobial agents (piperacillin, piperacillin/tazobactam, imipenem, meropenem, aztreonam, ceftazidime, amikacin, tobramycin, arbekacin, ciprofloxacin and colistin) were determined using the agar dilution test. The effects of aztreonam, colistin and the combination of aztreonam, ceftazidime and amikacin were determined by time-killing studies.
Bacteriostatic effects after 6 hours of drug exposure were observed in 12 strains (52.2%) of 23 strains of metallo-beta-lactamase-producing P. aeruginosa with 48 mg/l aztreonam, in 19 strains (82.6%) with the 3-drug combination of 16 mg/l aztreonam, 16 mg/l ceftazidime, and 4 mg/l amikacin, and in 23 strains (100%) with 2 mg/l colistin. Bactericidal effects after 6 h drug exposure were observed in 1 strain (4.3%) with 48 mg/l aztreonam, in 8 strains (30.4%) with the 3-drug combination and in all 23 strains (100%) with 2 mg/l colistin.
Evaluation of in vitro antimicrobial effects on metallo-beta-lactamase-producing P. aeruginosa revealed relatively good effects of the 3-drug combination of aztreonam, ceftazidime and amikacin and marked effects of colistin.
治疗产金属β-内酰胺酶的铜绿假单胞菌感染时，抗菌药物的选择有限。我们通过时间杀菌试验评估了氨曲南单独使用、多黏菌素单独使用以及氨曲南、头孢他啶和阿米卡星三联用药对23株产金属β-内酰胺酶的铜绿假单胞菌的抗菌效果。
所用菌株来自日本不同医院，经SpeI酶切后具有不同的脉冲场凝胶电泳图谱。采用琼脂稀释法测定11种抗菌药物（哌拉西林、哌拉西林/他唑巴坦、亚胺培南、美罗培南、氨曲南、头孢他啶、阿米卡星、妥布霉素、阿贝卡星、环丙沙星和多黏菌素）的最低抑菌浓度。通过时间杀菌研究确定氨曲南、多黏菌素以及氨曲南、头孢他啶和阿米卡星联合用药的效果。
在23株产金属β-内酰胺酶的铜绿假单胞菌中，12株（52.2%）在接触48mg/L氨曲南6小时后出现抑菌效果，19株（82.6%）在接触16mg/L氨曲南、16mg/L头孢他啶和4mg/L阿米卡星的三联用药后出现抑菌效果，23株（100%）在接触2mg/L多黏菌素后出现抑菌效果。1株（4.3%）在接触48mg/L氨曲南6小时后出现杀菌效果，8株（30.4%）在三联用药后出现杀菌效果，所有23株（100%）在接触2mg/L多黏菌素后出现杀菌效果。
对产金属β-内酰胺酶的铜绿假单胞菌的体外抗菌效果评估显示，氨曲南、头孢他啶和阿米卡星三联用药效果相对较好，多黏菌素效果显著。
