ROC曲线评价毛细管区带电泳用于α地中海贫血筛查的临床价值

Application of ROC cureves to assess the clinical value of capillary zone electrophoresis for screening alpha- thalassemia

目的探讨血红蛋白毛细管区带电泳用于α地中海贫血筛查的临床价值，确定血红蛋白A2（HemoglobinA2，HbA2）用于α地中海贫血诊断的截断值。方法收集66例d地中海贫血病例α地中海贫血组）和86例健康对照（正常对照组）。采集各组研究对象的静脉血进行血红蛋白毛细管区带电泳和α地中海贫血基因检测，通过建立受试者工作特征曲线（ROC曲线）对HbA2在α地中海贫血诊断中的统计学指标进行综合评价，并确定HbA2用于α地中海贫血诊断的截断值；统计工具采用SPSS17．0统计软件。结果d地中海贫血组和正常对照组的毛细管区带电泳的HbA2检测结果分别为（2．33±0．22）％和（2．65±0．29）％，α地中海贫血组明显低于正常对照组，差异有统计学意义（P〈0．01）。HbA2用于诊断α地中海贫血的ROC曲线下面积（AUC）为0．804（SE：0．035，95％CI：0．736～0．872），诊断价值具有统计学意义俨〈0．011；HbA2用于仪地中海贫血诊断的截断值为2．55％，对应的诊断灵敏度和特异度分别为60．5％和89．4％。结论血红蛋白毛细管区带电泳检测HbA2用于α地中海贫血筛查是目前较好的方法，具有较高的临床价值。

Objective To explore the clinical value of capillary zone electrophoresis for screening alpha-thalassemia and to ascertain the cutoff value of HbA2 for the diagnosis of alpha-thalassemia. Methods 66 alpha-thalassemia patients （alpha-thalassemia group） and 86 healthy controls （control group） were enrolled in this study. Hemoglobin capillary zone electrophoresis and detection of alpha-thalassemia gene were arried out in both groups. The receiver operating characteristic curve （ROC） was used to assess the value of HbA2 for the diagnosis of alpha-thalassemia and the cut-off value of HbA2 were ascertained. Statistical analysis was performed with the SPSS 17.0 statistical software. Results HbA2 level was （2.65 ＋ 0.29）% in the control group and （2.33 ~ 0.22）% in alpha-thalassemia group, with a significant difference （P〈0.01）. HbA2 level was lower in alpha-thalassemia group than in the control group. The area under receiver operating characteristic curve （AUC） of HbA2 was 0.804 （SE ： 0.035, 95% CI： 0.736-0.872） for diagnosis of alpha-thalassemia, and the diagnostic value had significant differences （P〈0.01）, with an optimal cut-off value of 2.55%. HbA2 showed a diagnostic sensitivity of 60.5% and specificity of 89.4%. Conclusions Hemoglobin capillary zone electrophoresis for HbA2 detection is a better method for screening alpha-thalassemia at present and has a higher clinical value.