MRSA对万古霉素、替考拉宁和利奈唑胺体外诱导耐药性比较

目的]通过比较万古霉素、替考拉宁和利奈唑胺体外诱导耐甲氧西林金葡菌(methicillin-resistant Staphylococcus aureus,MRSA)前后的最低抑菌浓度(minimal inhibitory concentration,MIC)变化,探讨此3种抗菌药物在诱导耐药性上有无差别。方法]琼脂二倍稀释法检测9株MRSA分别对万古霉素、替考拉宁、利奈唑胺的MIC,筛选出2株对3种药物均敏感的MRSA,用上述3种药物分别诱导2株MRSA25代,最后检测诱导后的MRSA菌株对3种药物的MIC,应用统计学软件进行数据分析。结果]经万古霉素、替考拉宁、利奈唑胺分别诱导25代后的MRSA菌株与各自诱导前比较,万古霉素和利奈唑胺的MIC升高2倍,替考拉宁的MIC升高2.67倍,但各组间MIC变化无差别,均未见耐药株产生;各组对照组的MRSA菌株经无药平皿传代,各药对其MIC无变化。结论]3种抗菌药物在诱导MRSA耐药上无差别。

Comparison on In-vitro Induction of Resistance in Methicillin-resistance Staphylococcus Aureus to Vancomycin, Teicoplanin and Linezolid

Objective]The paper aims to explore the difference of vancomycin,teicoplanin and linezolid in the inducing resistance of MRSA by measuring MIC before and after drug inducing.Methods]The MIC of Nine MRSA to vancomycin,teicoplanin and linezolid are identified by two-fold agar dilution method,and then two MRSA which are sensitive to the three drugs are found out.The two MRSA are induced separately by vancomycin,teicoplanin and linezolid for 25 generations.At last,the MIC of MRSA which have been induced to vancomycin,teicoplanin and linezolid are identified.The data is analyzed by SPSS 19.0.Results]After vancomycin,teicoplanin and linezolid inducing MRSA for 25 generations respectively,the MIC of vancomycin and linezolid increased 2 times and teicoplanin increased 2.67 times compared with those before drug induction.However,there was no difference of the change of MIC among the 3 groups.Additionally,no resistant strains were generated.The MIC of 3 drugs to MRSA strains in control groups in drug-free plates did not change after passage.Conclusions]The comparison of the three drugs at inducing resistance have no significant difference.