利奈唑胺对万古霉素敏感及耐药屎肠球菌的抗菌活性

The in vitro activity of linezolid against vancomycin-susceptible and-resistant Enterococcus faecium

目的评价利奈唑胺对临床分离万古霉素敏感及耐药屎肠球菌的体外抗菌活性。方法多重PCR法鉴定屎肠球菌万古霉素耐药基因类型，平皿二倍稀释法测定利奈唑胺等11种抗菌药物MIC值。结果75株临床分离万古霉索耐药屎肠球菌均携带vanA基因。万古霉素敏感及耐药屎肠球菌对利奈唑胺均敏感，MIC范围1-2mg／L。与红霉素、氨苄西林、左氧氟沙星和利福平相比，万古霉素敏感及耐药屎肠球菌的耐药率均在80％以上。万古霉素敏感屎肠球菌对高浓度庆大霉素、高浓度链霉素、四环素和氯霉素的耐药率分别为80．2％、13．9％、38．6％和37．6％；万古霉素耐药屎肠球菌对上述4种药物的耐药率分别为64．5％、8．0％、18．5％和5．3％。结论利奈唑胺对我国临床分离万古霉素敏感和耐药屎肠球菌均具有很好的体外抗菌活性。

Objective To investigate in vitro antibacterial activity of linezolid against vancomycin-susceptible Enterococcus faecium （VSE） and vancomycin-resistant Enterococcus faecium （VRE）. Methods The van genes were detected by multiplex PCR and MICs of linezolid and other 10 agents were determined by the two-fold agar dilution method. Result 75 VRE isolates were all carried vanA. All VSE and VRE isolates were susceptible to linezolid （MIC range 1-2mg/L）, more than 80% of VSE and VRE isolates were resistant to erythromycin, ampicillin, levofloxacin and rifampin. The resistance rates of VSE to high level gentamycin, high level streptomycin, tetracycline and chloramphenicol were 80.2%, 13.9%, 38. 6% and 37.6%, respectively. The resistance rates of VRE to the above-mentioned agents were 64.5%, 8.0%, 18.5% and 5.3%, respectively. Conclusion Linezolid showed potent activity against vancomycin-susceptible and resistant E. faecium.