Yang Jin-Ling, Cai Ren, Chen Da-Yu, Tan Jian-Qiang, Huang Li-Hua
Department of Medical Genetics, Liuzhou Maternal and Child Health Care Hospital, Liuzhou, Guangxi 545001, China.
Zhongguo Dang Dai Er Ke Za Zhi. 2018 Dec;20(12):990-993. doi: 10.7499/j.issn.1008-8830.2018.12.003.
To investigate the screening indices and their cut-off values for full-term neonates carrying β-thalassemia gene.
A retrospective analysis was performed for the clinical data of 1 193 full-term neonates who underwent β-thalassemia screening (hemoglobin analysis with dried blood spots on neonatal heel blood filter paper and mutation detection of 17 β-globin genes). A multivariate logistic regression analysis was used to investigate the association between screening indices and β-thalassemia gene, and the receiver operating characteristic (ROC) curve was used to analyze the value of screening indices in determining the presence or absence of β-thalassemia gene.
Of the 1 193 neonates, 638 carried β-thalassemia gene. Of the 1 193 neonates, 637 (53.39%) had no HbA, among whom 310 carried β-thalassemia gene and 327 did not carry this gene; 556 (46.61%) had HbA, among whom 328 carried β-thalassemia gene and 228 did not carry this gene. As for the neonates without HbA, the β-thalassemia gene group had a significantly lower HbA level and a significantly higher HbF level than the β-thalassemia gene-negative group (P<0.01). As for the neonates with HbA, the β-thalassemia gene group had a significantly lower HbA level and significantly higher HbF and HbA/HbA ratio than the β-thalassemia gene-negative group (P<0.01). In the neonates without HbA, HbA, gestational age, and HbA combined with gestational age had an area under the ROC curve (AUC) of 0.865, 0.515, and 0.870, respectively, in determining the presence or absence of β-thalassemia gene (P<0.01), and HbA and HbA combined with gestational age had a similar AUC and a certain diagnostic value. In the neonates with HbA, HbA, HbA/HbA ratio, and HbA combined with HbA/HbA ratio had an AUC of 0.943, 0.885, and 0.978, respectively, in determining the presence or absence of β-thalassemia gene. The HbA combined with HbA/HbA ratio had the largest AUC. In the neonates without HbA, HbA had the largest AUC in determining the presence or absence of β-thalassemia gene at the cut-off value of 11.6%, with a sensitivity of 85.81% and a specificity of 79.82%. In the neonates with HbA, an HbA of 16.1%-22.0% and an HbA/HbA ratio of >1.4 had the largest AUC in determining the presence or absence of β-thalassemia gene, with a sensitivity of 91.38% and a specificity of 91.89%.
HbA and HbA/HbA ratio are effective indices for screening out full-term neonates carrying β-thalassemia gene.
探讨足月新生儿β地中海贫血基因携带者的筛查指标及其临界值。
对1193例接受β地中海贫血筛查（采用新生儿足跟血滤纸片干血斑进行血红蛋白分析及17种β珠蛋白基因突变检测）的足月新生儿临床资料进行回顾性分析。采用多因素logistic回归分析探讨筛查指标与β地中海贫血基因的相关性，采用受试者操作特征（ROC）曲线分析筛查指标在判断β地中海贫血基因有无中的价值。
1193例新生儿中，638例携带β地中海贫血基因。1193例新生儿中，637例（53.39%）无HbA，其中310例携带β地中海贫血基因，327例不携带该基因；556例（46.61%）有HbA，其中328例携带β地中海贫血基因，228例不携带该基因。对于无HbA的新生儿，β地中海贫血基因组的HbA水平显著低于β地中海贫血基因阴性组，HbF水平显著高于β地中海贫血基因阴性组（P<0.01）。对于有HbA的新生儿，β地中海贫血基因组的HbA水平显著低于β地中海贫血基因阴性组，HbF和HbA/HbA比值显著高于β地中海贫血基因阴性组（P<0.01）。在无HbA的新生儿中，HbA、胎龄以及HbA与胎龄联合在判断β地中海贫血基因有无时的ROC曲线下面积（AUC）分别为0.865、0.515和0.870（P<0.01），HbA以及HbA与胎龄联合的AUC相近且有一定诊断价值。在有HbA的新生儿中，HbA、HbA/HbA比值以及HbA与HbA/HbA比值联合在判断β地中海贫血基因有无时的AUC分别为0.943、0.885和0.978。HbA与HbA/HbA比值联合的AUC最大。在无HbA的新生儿中，HbA在临界值为11.6%时判断β地中海贫血基因有无的AUC最大，灵敏度为85.81%，特异度为79.82%。在有HbA的新生儿中，HbA为16.1%-22.0%且HbA/HbA比值>1.4时判断β地中海贫血基因有无的AUC最大，灵敏度为91.38%，特异度为91.89%。
HbA及HbA/HbA比值是筛查足月新生儿β地中海贫血基因携带者的有效指标。
