抗菌新药左奥硝唑体外抗厌氧菌活性研究

In vitro activity of a new antibacterial agent levornidazole against anaerobic bacteria

目的测定左奥硝唑对临床分离375株厌氧菌的体外抗菌活性。方法根据CLSI 2012年版M11-A8标准,采用琼脂稀释法测定左奥硝唑对375株临床分离厌氧菌的最低抑菌浓度(MIC),并与奥硝唑、甲硝唑和右奥硝唑3种同类药物进行比较。结果左奥硝唑对大多数厌氧菌的体外抗菌活性强,与甲硝唑、奥硝唑及右奥硝唑相仿或略强。左奥硝唑对厌氧革兰阴性杆菌中的脆弱拟杆菌、多形拟杆菌的抗菌活性强,其MIC90值分别为0.5、1 mg/L;对厌氧革兰阳性杆菌中的艰难梭菌活性强、产气荚膜梭杆菌活性相仿,其MIC90值分别为0.25、2 mg/L;对厌氧革兰阳性球菌中的大消化链球菌也具有良好的抗菌活性,其MIC90值为1 mg/L。但左奥硝唑和其同类药物对厌氧革兰阴性球菌中的韦荣球菌抗菌活性均较差。结论左奥硝唑对厌氧革兰阴性杆菌、革兰阳性杆菌、革兰阳性球菌均具有较强的抗菌活性,与甲硝唑、奥硝唑及右奥硝唑相仿或略强。提示左奥硝唑具有良好的抗厌氧菌应用前景。

Objective To determine the in witro antibacterial activity of levornidazole against 375 anaerobic isolates. Methods Agar dilution method was used to determine the minimum inhibitory concentrations （MICs） of levornidazole, 3 comparators （metronidazolc, ornidazole and dextrornidazole） against 375 anaerobic isolates. Results For anaerobic gram-negative and gram- positive bacilli, and anaerobic gram-positive cocci, levornidazole displayed activity similar to or slightly higher than that of met ronidazole, ornidazole and dextrornidazole. I.evornidazole showed good activity against t3. fragilis, t3acteroides thetaiotaomi crotl, Clostridium dijJicile, Clostridium perfringens, and Peptostreptococcus magnus. The MIC,,0 value of levornidazole a- gainst the above-mentioned anaerobes was 0.5, 1, 0.25, 2 and 1 mg/L, respectively. However, levornidazole and the compa- rators had poor antibacterial activity against Veillonella spp. among anaerobic gram negative cocci. Conclusions the itz vitro anti-anaerobic activity of levornidazole is similar to or slightly higher than that of metronidazole, ornidazole and dex trornidazole. Levornidazole has good activity against both gram--negative and gram-positive anaerobic bacilli, and gram positive anaerobic cocci, suggesting its promising clinical use.