CRE对多粘菌素B的敏感性及两种检测方法的差异

Susceptibility of carbapenem-resistant Enterobacteriaceae to polymyxin B and difference between two detection methods

目的采用两种不同方法分析耐碳青霉烯类肠杆菌科细菌(CRE)对多粘菌素B的敏感性,为实验室选择药敏方法和临床合理用药提供依据。方法收集昆明医科大学第一附属医院2018年1-12月分离的230株CRE菌株,分别采用E-test法和微量肉汤稀释(BMD)法检测CRE对多粘菌素B的敏感性,分析两种药敏方法之间的差异性。结果菌株主要来源以痰为主,占70.87%(163株),其次是血(33株,14.35%)和分泌物(15株,6.52%),病原菌分布以肺炎克雷伯菌为主(205株)。CRE菌株E-test方法的敏感率为96.52%,耐药率为3.48%;BMD法的敏感率为95.65%,耐药率为4.35%。两种方法的基本一致率为95.65%,分类一致率为99.13%,极重大误差为0.87%。结论多粘菌素B对CRE有较好的抗菌活性,E-test法操作简便,和BMD法一致性好,可应用于临床常规药敏试验。

Objective To analyze the susceptibility of carbapenem-resistant Enterobacteriaceae(CRE)to polymyxin B by two different methods,so as to provide basis for the selection of antimicrobial susceptibility methods in laboratory and rational clinical amtimicrobial use.Methods 230 strains of CRE isolated from the First Affiliated Hospital of Kunming Medical University between January and December 2018 were collected,the susceptibility of CRE to polymyxin B was detected by E-test and broth microdilution(BMD)method respectively,differences between two methods were analyzed.Results The main source of bacteria was sputum(163 strains,70.87%),followed by blood(33 strains,14.35%)and secretion(15 strains,6.52%),Klebsiella pneumoniae was the main pathogen(205 strains).Susceptibility rate and resistant rate of CRE strains detected by E-test were 96.52%and 3.48%respectively;susceptibility rate and resistant rate of CRE strains detected by BMD method were 95.65%and 4.35%respectively;the basic consistent rate of two methods was 95.65%,classification consistent rate was 99.13%,and very major error was 0.87%.Conclusion Polymyxin B has good antimicrobial activity against CRE,E-test method is easy to be operated and is well consistent with BMD method,it can be used in clinical routine antimicrobial susceptibility testing.