万古霉素对徐州地区2015-2019年MRSA最低抑菌浓度值飘移特征

Characteristics of minimum inhibitory concentration drift of vancomycin against methicillin-resistant Staphylococcus aureus in Xuzhou in 2015-2019

目的回顾性分析万古霉素对耐甲氧西林金黄色葡萄球菌(MRSA)最低抑菌浓度(MIC)值变化趋势,为临床使用万古霉素治疗MRSA感染提供参考。方法按医院感染标准筛选2015-2019年徐州地区3所三级甲等综合性医院临床标本分离的非重复MRSA共900株,收集其MIC值,比较重症监护病房(ICU)与非ICU科室万古霉素对MRSA的MIC值,分析相关特征。结果900株MRSA全部对万古霉素敏感,2015-2019年万古霉素对MRSA的MIC均值分别为(1.058±0.232)、(1.100±0.272)、(1.108±0.266)、(1.122±0.273)、(1.147±0.298)μg/mL,组间整体比较,差异有统计学意义(P<0.05);ICU科室MIC均值分别为(1.159±0.303)、(1.253±0.344)、(1.320±0.331)、(1.413±0.289)、(1.451±0.278)μg/mL,组间整体比较差异有统计学意义(P<0.05);非ICU科室MIC均值分别为(0.995±0.134)、(1.005±0.135)、(1.005±0.091)、(1.016±0.155)、(1.006±0.142)μg/mL,组间整体比较,差异无统计学意义(P>0.05)。2015-2019年ICU和非ICU科室MIC均值同年份比较,差异均有统计学意义(均P<0.05);万古霉素对MRSA的MIC≥1.5μg/mL的比例逐年增加。结论2015-2019年徐州地区未发现耐万古霉素MRSA,万古霉素对MRSA的MIC值存在漂移,主要来自ICU科室。对ICU科室万古霉素MIC≥1.5μg/mL的MRSA菌株及其感染患者应重点监控,积极治疗,防止感染暴发。

Objective To retrospectively analyze the changing trend of minimum inhibitory concentration(MIC)of vancomycin against methicillin-resistant Staphylococcus aureus(MRSA),provide reference for the clinical use of vancomycin in the treatment of MRSA infection.Methods 900 strains of non-repetitive MRSA from clinical specimens in 3 tertiary first-class general hospitals in Xuzhou City in 2015-2019 were selected according to the standard of healthcare-associated infection(HAI),MIC values were collected,MICs of vancomycin to MRSA between intensive care units(ICUs)and non-ICUs were compared,and related characteristics were analyzed.Results 900 strains of MRSA were all sensitive to vancomycin,the mean MIC values in 2015-2019 were(1.058±0.232),(1.100±0.272),(1.108±0.266),(1.122±0.273)and(1.147±0.298)μg/mL respectively,and there were significant differences among groups(P<0.05);the mean MICs of ICU were(1.159±0.303),(1.253±0.344),(1.320±0.331),(1.413±0.289)and(1.451±0.278)μg/mL respectively,there were significant differences among groups(P<0.05);the mean MICs of non-ICUs were(0.995±0.134),(1.005±0.135),(1.005±0.091),(1.016±0.155)and(1.006±0.142)μg/mL respectively,there were no significant differences among groups(P>0.05).The mean MICs between ICUs and non-ICUs in the same year of 2015-2019 were all significantly different(all P<0.05);proportion of MIC≥1.5μg/mL of vancomycin against MRSA had an increasing trend year by year.Conclusion Vancomycin-resistant MRSA was not found in Xuzhou in 2015-2019;vancomycin has MIC drift to MRSA,which mainly comes from ICUs.MRSA strains with vancomycin MIC≥1.5μg/mL and infected patients in ICU should be given stress surveillance and active treatment to prevent infection outbreak.