2011—2015年四川省金黄色葡萄球菌对万古霉素及利奈唑胺耐药性变迁

Changes in resistance of Staphylococcus aureus to vancomycin and linezolid in Sichuan Province in 2011-2015

目的了解四川省金黄色葡萄球菌对万古霉素、利奈唑胺耐药情况,为临床抗感染治疗提供参考依据。方法收集四川省71所医院2011—2015年临床分离的金黄色葡萄球菌、耐甲氧西林金黄色葡萄球菌(MRSA),并计算每年万古霉素与利奈唑胺对金黄色葡萄球菌、MRSA的最低抑菌浓度(MIC)值。结果 5年共收集51 976株金黄色葡萄球菌,包括MRSA14 361株,MRSA检出率由2011年的36.02%下降至2015年的25.56%,呈下降趋势(χ2=160.72,P<0.05)。2011—2015年万古霉素对金黄色葡萄球菌的MIC50值分别为:1、0.5、0.5、1、1μg/mL,MIC90值由1μg/mL上升至2μg/mL;利奈唑胺MIC50值均为2μg/mL,MIC90值由2μg/mL上升至4μg/mL。2011—2015年万古霉素对MRSA的MIC50、MIC90值变化较明显,分别由0.5、1μg/mL上升至2μg/mL;利奈唑胺MIC50值均为2μg/mL,MIC90值由2μg/mL上升至4μg/mL。结论 MRSA的检出率有下降趋势,但万古霉素、利奈唑胺对其MIC50及MIC90值总体有上升趋势,需继续加强细菌耐药监测,为临床合理应用抗菌药物提供帮助。

Objective To investigate the resistance of Staphylococcus aureus （S.aureus） to vancomycin and linezolid in Sichuan Province, and provide reference for clinical anti-infection treatment.Methods S.aureus and methicillin-resistant S.aureus（MRSA） from 71 hospitals in Sichuan Province in 2011-2015 were collected, minimum inhibitory concentration（MIC） values of vancomycin and linezolid against S.aureus and MRSA in each year were calculated.Results A total of 51 976 strains of S.aureus were collected in 5 years, 14 361 of which were MRSA, isolation rate of MRSA decreased from 36.02% in 2011 to 25.56% in 2015, which showed a downward trend （x2=160.72,P〈0.05）.From 2011 to 2015, MIC50 of vancomycin against S.aureus were 1, 0.5, 0.5, 1, and 1μg/mL respectively,MIC90 increased from 1μg/mL to 2μg/mL;the mean MIC50 of linezolid was 2μg/mL,MIC90 increased from 2μg/mL to 4μg/mL.Change in MIC50 and MIC90 of vancomycin against MRSA in 2011-2015 were obvious, which increased from 0.5, 1μg/mL to 2μg/mL respectively;the mean MIC50 of linezolid was 2μg/mL,MIC90 increased from 2μg/mL to 4μg/mL.Conclusion The isolates rate of MRSA had a decreasing trend,but there is a upward trend of MIC50 and MIC90 of vancomycin and linezolid against MRSA, bacterial resistance surveillance needs to be strengthened to provide evidence for rational clinical antimicrobial therapy.