舒巴坦联合9种抗菌药物对耐碳青霉烯类鲍曼不动杆菌体外抗菌活性研究

In vitro activity of Sulbactam in combination with nine antibacterial agents against carbapenem-resistant Acinetobacter baumannii

目的:评价舒巴坦与9种临床常用抗菌药物联合用药对耐碳青霉烯类鲍曼不动杆菌(CRAB)的体外抗菌效应。方法:从临床分离得到24株CRAB。采取微量肉汤稀释法测定10种抗菌药物单一用药对CRAB的最低抑菌浓度(MIC)。采用棋盘法设计,微量肉汤稀释法测定舒巴坦分别联合9种抗菌药物对CRAB的MIC,并计算部分抑菌浓度指数(FIC)判定联合效应。结果:9种抗菌药物联用舒巴坦后的MIC均比单用时降低;联用后替加环素、多西环素、环丙沙星、左氧氟沙星的MIC_(50)均低于对应单药敏感折点,替加环素的MIC_(90)达到单药的敏感折点。舒巴坦与9组联合用药均未出现拮抗作用;舒巴坦联合阿米卡星的协同作用最强,其次为美罗培南、帕尼培南、亚胺培南、多西环素、替加环素。结论:与单药相比,9种药物联用舒巴坦对CRAB的体外抑菌作用均有增强效果。9种抗菌药物联合舒巴坦有效地降低MIC值,其中多西环素、替加环素、环丙沙星和左氧氟沙星,可使其MIC值降至敏感范围内。

OBJECTIVE To evaluate the in vitro activity of sulbactam combined with nine antibacterial agents against carbapenem resistant Acinetobacter baumannii(CRAB).METHODS 24 strains of CRAB clinical isolates were collected.The minimum inhibitory concentrations(MICs)of 10 antimicrobial agents was determined by the broth microdilution method.The MICs of sulbactam combined with nine antibacterial agents against CRAB was detected by microdilution method and chessboard method,and the fractional inhibitory concentration index(FIC)was calculated according to MIC results.RESULTS Compared with the antibiotics single use groups,the MICs of nine antibiotics combined with sulbactam were lower.The MIC50 of tigecycline,doxycycline,ciprofloxacin and levofloxacin were lower than those of the corresponding monotherapy.The MIC90 of tigecycline combined with sulbactam reached the single drug sensitive breakpoint.The combination of the 9 groups was not antagonistic.Sulbactam combined with amikacin showed the strongest synergistic effect,followed by meropenem,panipenem,imipenem,doxycycline,tigecycline.CONCLUSION Sulbactam combined with 9 kinds of drugs can enhance in vitro antibacterial effect of CRAB.Nine antibacterial agents can effectively reduce the MIC values when combined with sulbactam.Doxycycline,tigecycline,ciprofloxacin and levofloxacin reduce the MICs to a sensitive range.