干血斑毛细管电泳技术在新生儿α-地中海贫血筛查中的应用

Application of dried blood spot capillary electrophoresis in screening of α-thalassemia among neonates

目的：探讨基于干血斑的毛细管电泳技术在新生儿α-地中海贫血筛查中的应用价值。方法：新生儿出生48~72 h从足跟内或外侧采血4滴制成干血斑,利用毛细管电泳技术对干血斑中Hb Bart＇s进行定量分析,对阳性标本（含Hb Bart＇s）进行地中海贫血基因诊断;同时,抽取筛查阴性100例进行α-地中海贫血基因诊断。结果：共筛查新生儿干血斑标本58 150例,筛查出α-地中海贫血阳性2 635例,阳性率4.53%;对召回复查的271例初筛阳性病例进行地贫基因诊断,其中αCSα/αα26例、αQSα/αα5例、--SEA/αα184例、（--SEA/αα）/（-28/N）1例、（--SEA/αα）/（17/N）1例、（--SEA/αα）/（41-42/N）4例、--SEA/αWSα3例、（--SEA/αα）/（654/N）1例、-α3.7/-α3.7 1例、-α3.7/αα4例、-α3.7/αCSα1例、-α3.7/αWSα1例、--SEA/-α3.7 9例、-α3.7/-α4.2 2例、-α4.2/αα2例、αα/αα26例,阳性共245例,阳性率90.41%。100例筛查阴性者中,发现地贫基因携带者2例,其中-α3.7/αα1例、-α4.2/αα1例,均为静止型,假阴性率为2.00%。结论：利用毛细管电泳技术对新生儿干血斑中Hb Bart＇s进行定量分析,对新生儿α-地中海贫血筛查准确性高。利用干血斑替代脐血进行新生儿α-地中海贫血筛查,标本运输和保存更方便,更利于此项目的广泛开展和新生儿疾病筛查的管理,值得广泛推广应用。

Objective： To explore the application value of capillary electrophoresis based on dried blood spot in screening of α-thalassemia among neonates. Methods： Four drops of blood were taken from heel of neonates at 48- 72 hours after birth,dried blood spot was prepared,Hb Bart＇s amount in dried blood spot was analyzed quantitatively by capillary electrophoresis. The positive specimens（ containing Hb Bart＇s） were recalled for genetic diagnosis of thalassemia; at the same time,100 positive neonates were selected for genetic diagnosis of α- thalassemia. Results： A total of 58 150 neonatal dried blood spot specimens were screened,2 635 neonates were diagnosed as α-thalassemia,the positive rate was 4. 53%; 271 positive neonates in primary screening were recalled and reexamined for genetic diagnosis of thalassemia,including 26 neonates of αCSα / αα,5 neonates of αQSα / αα,184 neonates of-- SEA / αα,1 neonate of（-- SEA / αα） /（- 28 /N）,1 neonate of（-- SEA/αα） /（ 17 /N）,4 neonates of（-- SEA/αα） /（ 41- 42 /N）,3 neonates of-- SEA/αWSα,1neonate of（-- SEA / αα） /（ 654 / N）,1 neonate of- α3. 7 /- α3. 7,4 neonates of- α3. 7 / αα,1 neonate of- α3. 7 / αCSα,1 neonate of- α3. 7 / αWSα,9 neonates of-- SEA /- α3. 7,2 neonates of- α3. 7 /- α4. 2,2 neonates of- α4. 2 / αα,26 neonates of αα / αα,a total of 245 neonates were positive,the positive rate was 90. 41%. Among 100 negative neonates,2 neonates were thalassemia gene carriers,including one neonate of- α3. 7 / αα and one neonate of- α4. 2 / αα,all of them were silent type,the false negative rate was 2. 00%. Conclusion： The accuracy of quantitative analysis of Hb Bart＇s amount in dried blood spot by capillary electrophoresis is high for screening ofα- thalassemia among neonates. Dried blood spot is more convenient for transportation and preservation of specimens compared with cord blood specimens for screening of α- thalassemia among neonates,which is more beneficial for conducting the project and managing screening of neonatal diseases,the method is worthy of popularization and application in clinic.