毛细管电泳在新生儿β-地中海贫血筛查中的应用

Application of capillary electrophoresis for screening of the β-thalassemia in neonates

目的了解广东省地区新生儿β-地中海贫血(β-地贫)的携带率,评价毛细管电泳法(capillary electrophoresis,CE)用于筛查新生儿β-地贫的可行性,探讨使用血红蛋白A(hemoglobin A,Hb A)筛查新生儿期β-地贫的最适宜截断值。方法研究对象为广东省21个地级市的脐血样本13 396例,采用Sebia第二代全自动毛细管电泳仪对新生儿脐血进行血红蛋白成分分析,应用地中海贫血液相芯片技术对全部样本进行基因水平的验证。以基因结果为金标准使用受试者特征工作曲线(ROC)评价CE用于筛查新生儿β-地贫的敏感度和特异度,并选取Hb A的最佳截断值。结果在13 396份新生儿脐血中检出β-地贫500例,携带率为3.73%,其中轻型β-地贫498例,中间型β-地贫2例。Hb A的ROC曲线下面积为0.927,选取Hb A的截断值为13%时,其筛查新生儿β-地贫的灵敏度为98.4%,特异度为76.2%。结论广东省新生儿β-地贫携带率高,CE可用于筛查新生儿β-地贫,并且选取Hb A的截断值为13%时具备较好的筛查准确性。

Objective To investigate the prevalence of β-thalassemia in neonates of Guangdong Province and to evaluate the feasibility and the best cut -off value of hemoglobin A （ Hb A） by capillary electrophoresis （ CE） system for screening β-thalassemia in neonates .Methods A total of 13 396 neonate cord blood samples were collected from 21 cities of Guangdong Province .Hemoglobin fractions and quantification were performed by Sebia automated capillary elec -trophoresis .Molecular analysis of the β-goblin genes was carried out for all the samples as gold standard , while 17 com-mon point mutations of β-thalassemia were examined by a suspension array system .Receiver operating characteristic curve （ROC curve） analysis was utilized to illustrate the screening performance of the percentage of Hb A , and to obtain the best cut-off value of Hb A .Results Among the 13 396 cord blood samples selected , 500 neonates were diagnosed asβ-thalassemia and the carrier rate was 3.73%.The cut-off value of percentage of Hb A was 13%, with the sensitivity of 98.4%and the specificity of 76.2%.Conclusion The prevalence of β-thalassemia is high in Guangdong Province . CE is suitable for screening β-thalassemia in neonates , and the best cut -off value of Hb A is 13.0%.