熔解曲线法在结核分枝杆菌药敏试验质量评估中的应用  

Application of melting curve assay in the quality assessment of drug susceptibility test on Mycobacterium tuberculosis

作　　者：田际云[1] 武洁[2] 李静[2] 江渊[2] 王莉莉[2] 沈鑫[2] 高谦[1] 

机构地区：[1]复旦大学上海医学院医学分子病毒学重点实验室,200032 [2]上海市疾病预防控制中心结核病防治科

出　　处：《中华结核和呼吸杂志》2015年第2期105-109,共5页Chinese Journal of Tuberculosis and Respiratory Diseases

基　　金：上海市卫生系统优秀人才培养计划（XYQ2011051）;上海市卫生局青年科研项目（2011Y033）

摘　　要：目的 探讨熔解曲线法用于结核分枝杆菌药敏试验质量评估的可行性.方法 以2009年5月至2012年9月间上海市松江区和其他5个区县级结核病诊疗机构收集的2 204株结核分枝杆菌临床菌株为研究对象,比较熔解曲线法的耐药基因型检测结果与比例法药敏试验结果的符合度.对松江区结果不一致的菌株进行盲法复检,并用基因测序方法确定耐药突变类型.结果 上海市松江区的评估结果显示,耐药基因型的分子诊断结果与利福平和异烟肼的药敏试验结果高度一致（κ值分别为0.97和0.99）,利福平耐药株的阳性符合度、阴性符合度及总符合度分别为97.6％（41/42）、100％ （757/757）和99.9％（788/799）,异烟肼分别为100％ （72/72）、99.9％（726/727）和99.9％（798/799）.盲法复检显示,熔解曲线法诊断的2次检测结果完全相同,具有很好的重复性.而在其他5个诊疗机构（A ～E）,熔解曲线法与药敏试验结果的阳性符合度为87.5％（21/24）、80.8％（21/26）、87.5％ （14/16）、82.9％（29/35）和60.9％ （14/23）,异烟肼耐药检测相关数据为88.2％（30/34）、65.6％（21/32）、85.0％（17/20）、68.3％（41/60）和62.5％（15/24）,不同诊疗机构之间结果差异具有统计学意义,提示部分诊疗机构可能存在漏检耐药病例的问题.结论 熔解曲线法操作简便,耗时短,且重复性好,能及时发现日常工作中存在的问题,适于药敏试验的质量评估.Objective To evaluate the feasibility of melting curve assay technologies in quality assessment of drug susceptibility test （DST） on Mycobacterium tuberculosis.Methods During May 2009 to September 2012,a total of 2 204 MTB isolates were collected in Shanghai Songjiang District and 5 other county level TB institutes.DST results of these isolates were verified by the melting curve assay.Isolates with inconsistent phenotype and genotype results were retested and sequenced for any drug resistance mutations.Results Evaluation at Songjiang District showed high consistency of the melting curve assay with rifampicin and isoniazid DST results （kappa =0.97 and 0.99,respectively）.Consistency of the two methods were 97.6% （41/42）,100% （757/757） and 99.9% （788/799） in rifampicin resistant,susceptible,and total cases,respectively.As for isoniazid resistance detection,the consistency were 100% （72/72）,99.9% （726/727）,and 99.9% （798/799） in resistant,susceptible,and total cases,respectively.Blinded re-examination of isolates with inconsistent genotype and phenotype resistance confirmed the good reproducibility of melting curve assay,which yielded the same results as the first test.Quality assessment at institutes A,B,C,D and E,however,showed consistency of only 87.5% （21/24）,80.8% （21/26）,87.5% （14/16）,82.9% （29/35）,60.9% （14/23） in rifampicinresistant cases,and 88.2% （30/34）,65.6% （21/32）,85.0% （17/20）,68.3% （41/60）,62.5% （15/24） in isoniazid resistant cases.As the reliability of DST results significantly varied among different areas,our finding indicated that there were misdiagnosed drug resistant cases in some field sites.Conclusion The melting curve assay for MTB DST is fast,easy to use,reproducible,and able to identify mistakes in daily work.Therefore,it is a suitable tool for the quality assessment of conventional DST results.

关 键 词：分枝杆菌 结核 熔解曲线法 药敏试验 质量评估 

分 类 号：R378.911[医药卫生—病原生物学]