RDW筛查地中海贫血诊断界值的建立及其与MCV、MCH、HbA_(2)联合筛查的价值

Diagnostic Cut-Off Value of RDW for Screening Thalassemia and the Combined Determination of MCV,MCH,HbA and RDW

目的:探讨红细胞分布宽度(RDW)与红细胞平均体积(MCV)、平均红细胞血红蛋白含量(MCH)、血红蛋白(Hb) A_(2)联合筛查方案在地中海贫血(简称地贫)筛查中的应用价值。方法:检测地贫患者和体检健康者(健康对照组)的RDW水平,比较两组RDW水平变化。绘制受试者工作曲线(ROC),计算约登指数,评价RDW的诊断性能,建立RDW筛查地贫诊断界值。另外选取621例疑似地贫患者,设置3组筛查方案,分别为MCV+MCH+HbA_(2)、MCV+MCH+RDW(>16.0)+HbA_(2)和MCV+MCH+RDW(> 15.15)+HbA_(2),对3组筛查方案进行性能评价。结果:地贫患者RDW水平明显高于体检健康者(健康对照组),差异具有统计学意义(P <0.05)。选用RDW> 15.15作为筛查地贫的诊断界值。MCV+MCH+RDW(> 15.15)+HbA_(2)地贫筛查方案的敏感性、特异性、阳性预测值、阴性预测值、漏诊率、诊断符合率分别为75.46%、48.83%、26.50%、89.06%、24.54%和54.06%。结论:建立了RDW筛查地贫的诊断界值,在MCV(<82.0 fl)+MCH(<27.0 pg)+HbA_(2)(<2.5%或≥3.5%)+RDW(> 15.15)筛查方案中将RDW> 15.15作为诊断界值在3种地贫筛查方案中具有较好的筛查价值。

Objective:To explore the value of red cell distribution width(RDW),mean corpuscular volume(MCV),mean corpuscular hemoglobin(MCH) and hemoglobin(Hb) A_(2) combined determination scheme for screening thalassemia.Methods:The RDW levels of thalassemia group and healthy control group were detected and compared.The efficiency of RDW for screening thalassemia was evaluated by receiver operating characteristic(ROC)curve.The diagnostic cut-off value of RDW was also acquired by Youden index.Then,3 groups for thalassemia screening scheme were set,including MCV+MCH+HbA_(2),MCV+MCH+RDW(> 16.0)+HbA_(2) and MCV+MCH+RDW(> 15.15)+HbA_(2).The performances of the 3 groups were evaluated through screening 621 clinical suspected cases of thalassemia.Results:The RDW level in thalassemia group was significantly higher than that in healthy control group(P <0.05).The diagnostic cut-off value for screening thalassemia was RDW> 15.15,when the Youden index was the biggest among all data.The sensitivity,specificity,positive predictive value,negative predictive value,false negative rate and consistency rate of MCV+MCH+RDW(> 15.15)+HbA_(2) group was 75.46%,48.83%,26.50%,89.06%,24.54%,and 54.06%,respectively.Conclusion;The diagnostic cut-off value of RDW for thalassemia screening has been established.The group of MCV(<82.0 fl)+MCH(<27.0 pg)+HbA_(2)(<2.5% or ≥3.5%)+RDW(> 15.15) has a best efficiency among the 3 groups to screen thalassemia.