脐带血红细胞参数检验在α-地中海贫血筛查中的应用价值

Application value of cord blood erythrocyte parameter test in the screening ofα-thalassemia

目的研究脐带血红细胞参数检验在α-地中海贫血筛查中的应用价值。方法选择2018年1—12月于南方医科大学附属中山市博爱医院出生且基因诊断为α-地中海贫血的202例新生儿作为α-地中海贫血组,另外选择802名正常新生儿作为正常对照组。对所有新生儿进行脐带血血常规检验,并抽取外周血进行α-地中海贫血基因检测,观察和比较两组新生儿脐带血中红细胞计数(RBC)、血红蛋白(Hb)、红细胞分布宽度(RDW)、血细胞比容(HCT)、平均红细胞体积(MCV)、平均红细胞血红蛋白量(MCH)和平均红细胞血红蛋白浓度(MCHC)的水平。绘制受试者工作特征曲线(ROC曲线)并计算曲线下面积(AUC),比较各参数单独或联合检测的诊断效能。结果202例α-地中海贫血患儿基因型中,以--^(SEA)/αα基因型最常见〔49.50%(100/202)〕,其次为-α^(3.7)/αα〔33.17%(67/202)〕;α-地中海贫血组的RBC和RDW均明显高于正常对照组〔RBC(×10^(12)/L):4.88±0.68比4.43±0.46,RDW:(16.66±1.22)%比(14.96±0.38)%,均P<0.01〕,而Hb、MCV、MCH、MCHC和MCV/RBC水平均明显低于正常对照组〔Hb(g/L):147.78±17.20比154.96±15.74,MCV(fL):101.87±8.20比111.37±5.10,MCH(pg):30.56±3.23比35.02±1.83,MCHC(g/L):299.62±14.19比314.76±15.63,MCV/RBC:21.52±5.09比25.45±3.39,均P<0.01〕。MCH的截断值为33.65 pg时,诊断α-地中海贫血的敏感度为所有指标中最高(83.2%);MCV+MCH联合检测的特异度最高(94.6%);MCH+MCV/RBC联合检测对α-地中海贫血的检验效能最高(AUC=0.889),其对应的敏感度、特异度、阳性预测值和阴性预测值分别为81.7%、87.8%、62.7%和95.0%。结论脐带血血常规红细胞参数联合应用对α-地中海贫血的诊断具有较高的敏感度和特异度,能够为该疾病临床诊断和防控提供重要的参考依据,值得临床应用和推广。

Objective To investigate the application value of cord blood erythrocyte parameter test in the diagnosis ofα-thalassemia.Methods 202 newborns withα-thalassemia who were born in Zhongshan Boai Hospital Affiliated to Southern Medical University from January to December 2018 were selected asα-thalassemia group,and 802 normal newborns were selected as normal control group.Cord blood routine tests were performed on all newborns,and peripheral blood was obtained forα-thalassemia gene testing.The levels of red blood cell count(RBC),hemoglobin(Hb),red cell distribution width(RDW),hematocrit(HCT),mean corpuscular volume(MCV),mean corpuscular hemoglobin(MCH)and mean corpusular hemoglobin concentration(MCHC)of neonatal cord blood in two groups were observed and compared.The receiver operator characteristic curve(ROC)was drawn and the area under curve(AUC)was calculated.The diagnostic efficiencies of each parameter alone and combined detection were compared.Results The--^(SEA)/ααgenotype was the most common in 202 cases ofα-thalassaemia[49.50%(100/202)],followed by-α^(3.7)/αα[33.17%(67/202)].The levels of RBC and RDW inα-thalassemia group were higher than those in normal control group[RBC(×10^(12)/L):4.88±0.68 vs.4.43±0.46,RDW:(16.66±1.22)%vs.(14.96±0.38)%,both P<0.01],and the levels of Hb,MCV,MCH,MCHC and MCV/RBC were lower than those in normal control group[Hb(g/L):147.78±17.20 vs.154.96±15.74,MCV(fL):101.87±8.20 vs.111.37±5.10,MCH(pg):30.56±3.23 vs.35.02±1.83,MCHC(g/L):299.62±14.19 vs.314.76±15.63,MCV/RBC:21.52±5.09 vs.25.45±3.39,all P<0.01].When the cut-off value of MCH was 33.65 pg,the sensitivity to diagnoseα-thalassemia was the highest of all indicators(83.2%),and the specificity of MCV+MCH was the highest(94.6%).The combination of MCH+MCV/RBC had the highest test efficiency forα-thalassemia(AUC=0.889),The corresponding sensitivity,specificity,positive predictive value and negative predictive value were 81.7%,87.8%,62.7%and 95.0%,respectively.Conclusion The combined application of cord blood routine erythrocyte parameters has high sensitivity and specificity in the diagnosis ofα-thalassemia,which can provide important reference for the clinical diagnosis,prevention and control ofα-thalassemia,and is worthy of clinical application and promotion.