构建ROC曲线确定Hb A2筛查β地中海贫血的临界值

Determining Hb A2 Critcal Value of Screening Beta Thalassemia by Establishing the ROC Curve

目的:通过构建ROC曲线,探讨血红蛋白(Hb)A2筛查β地中海贫血的临界值。方法:分析河源市妇幼保健院2016年1月至2017年8月进行地中海贫血筛查和地中海贫血基因诊断的1274例数据,将其分为正常对照组、α地中海贫血组、β地中海贫血组和α复合β地中海贫血组。以Hb A2不同的临界值计算筛查β地中海贫血敏感度、特异度,再绘制Hb A2筛查β地中海贫血的受试者工作曲线。结果:本研究中有184例β地中海贫血,平均Hb A2含量为(5.29±0.66)%,基因类型分布频率由高到低依次为IVS–Ⅱ–654、CD4–42、CD28、CD17、CD26、CD27–28、CD14–15、CD29,5例Hb E病毛细管电泳结果出现Hb E,且Hb E含量较高;α地中海贫血复合β地中海贫血主要表现为Hb A2增高,平均Hb A2的含量为(5.29±0.62)%。通过构建ROC曲线获得本实验室Sebia全自动毛细管Hb电泳系统对β地中海贫血筛查的最佳临界值为≥3.85%。结论:从ROC曲线下面积可知,Sebia全自动毛细管电泳系统对于β地中海贫血的筛查具有较高的准确性,其Hb A2的截断值为≥3.85%。

Objective To study the method of determining the Hb A2 critical value of screening beta thalassemia by establishing the ROC curve. Method Analysis of 1274 cases of data on thalassemia screening and thalassemia gene diagnosis from January 2016 to August 2017 in Heyuan women and children＇s hospital and health institute. They were divided into normal control group, α thalassemia group, β thalassemia group and α complex β thalassemia group. Calculating the screening beta thalassemia sensitivity and specificity for the different Hb A2 critical value, and drawing the Hb A2 working curve screening beta thalassemia. Results In this study, there are 184 cases of thalassemia, the average content of Hb A2 is（5.29 ± 0.66） %, genetype frequency distribution from high to low is IVS– Ⅱ –654、CD4–42、–28、CD17、CD26、CD27–28、CD14–15、–29, 5 cases of hemoglobin E disease by capillary electrophoresis has Hb E, and the content of Hb E was high;alpha thalassemia compound beta thalassemia Hb A2 usually is increased, the average content of Hb A2 was（5.29 ± 0.62） %. Constructing ROC curves and know the bester Hb A2 critical value of screening beta thalassemia is 3.85 % in our laboratory Sebia automatic capillary electrophoresis hemoglobin system. Conculsions The area under the ROC curve shows that the Sebia automatic capillary electrophoresis system has high accuracy in screening beta thalassemia, the Hb A2 cutingt off value is more than 3.85 %.