【作者】 李辉；

【导师】 俞云松；

【作者基本信息】 浙江大学 ， 内科学（传染病学）， 2019， 硕士

【摘要】 目的:由于能选择的有效治疗手段极少,碳青霉烯耐药鲍曼不动杆菌杆菌感染日益成为一个威胁全球人民健康的重大问题。而多粘菌素被认为是最后的治疗手段。现在,有很多测定多粘菌素药敏的方法,如加入吐温-80的微量肉汤稀释法(BMD-P80)、E-TEST试纸法、微量肉汤稀释法(BMD)、琼脂稀释法(AD)。然而,各方法之间的差异没有很好的研究结果。该研究旨在评价四种多粘菌素体外药敏方法对耐碳青霉烯鲍曼不动杆菌的敏感性,和多粘菌素异质性耐药的发生率,为抗菌药物合理应用提供科学依据。方法:随机选择202株2010年1月至12月保存在菌库中的,从浙江省12家医院内收集到的碳青霉烯耐药鲍曼不动杆菌,采用四种药敏方法测定最小抑制浓度值。并选择其中29株不同MIC值的菌株,采用群体谱分析方法(PAP)分析多粘菌素对碳青霉烯耐药鲍曼不动杆菌的异质性耐药。结果:依据欧盟药敏试验标准(EUCAST)的折点,四种测定方法(BMD-P80、E-TEST、BMD、AD)的多粘菌素敏感率分别是100%、100%、99.5%、90.6%。使用AD方法产生的重大误差(MEs)有9.4%而E-TEST和BMD只有0.5%,而且,使用AD方法的结果判断最小一致性(EA)为9.4%,与BMD-P80方法比较其中有179株菌株的浓度值≥3个稀释度,所有方法都没有发现非常重大误差(VMEs)。在29株碳青霉烯耐药鲍曼不动杆菌中有异质性的为65%,有异质性耐药的是31%。结论:琼脂稀释法因其测定时MIC值升高导致误判的结果不推荐作为首选的体外测定多粘菌素敏感性的方法,而BMD-P80、E-TEST、BMD等可以作为选择多粘菌素为潜在治疗药物时的药敏试验方法。在中国的耐碳青酶烯鲍曼不动杆菌中发现非常高的异质性和异质性耐药,所以在使用多粘菌素前及使用中监测MICs显得非常重要。更多还原

【Abstract】 Objective:The current study aimed at evaluating the 4 available methods to test in vitro susceptibility to colistin and observing the degree of heteroresistance in CRAB species in China.Methods:To evaluate the methods,a total of 202 CRAB species isolated from 12 hospitals in Zhejiang province,China,collected from January to December in 2010 were employed retrospectively.Colistin minimum inhibitory concentrations(MICs)were determined by the 4 different methods.Population analysis profiles(PAPs)were also conducted in 29 CRAB strains.Results:The proportions of colistin-sensitive isolates were 100%,100%,99.5%,and 90.6%by BMD-P80,E-test,BMD,and AD methods,respectively,according to the EUCAST breakpoints.The AD methods produced an excessive number of major errors(MEs)(9.4%),while E-test and BMD produced 0.5%MEs.Moreover,the AD method resulted in a minimum essential agreement(EA)at 9.4%,and 179 isolates obtained a higher(≥3 log 2)number of dilutions than the BMD-P80.Not very major errors(VMEs)were found by any of the tested methods.In 29 selected CRAB isolates,a total of 65%were heterogeneous and the rate of heteroresistance was 31%.Conclusion:The AD method was not a prior choice of in vitro colistin susceptibility testing because it led to false colistin resistance results.E-test,BMD,and BMD-P80 may be more reliable to test the susceptibility when colistin is considered as a potential therapeutic agent.A high rate of heterogeneous and heteroresistant species were found in CRAB in China;it highlighted the importance of MICs monitoring before and through the colistin therapy period.更多还原