采用ROC曲线评价β珠蛋白生成障碍性贫血杂合子血液学指标诊断价值

Evaluation of hematological parameters of β-thalassemia heterozygote by ROC curve

目的采用受试者工作特征曲线(ROC曲线)评价β珠蛋白生成障碍性贫血(β地中海贫血,简称β地贫)杂合子血液学指标,确定平均红细胞体积(MCV)、红细胞脆性(EF)、血红蛋白(Hb)A2及HbF的最佳截断值(cutoff值)。方法以基因诊断结果为金标准,采用ROC曲线分析MCV、EF、HbA2及HbF最佳cutoff值;评价单项及多项指标联合检测的诊断价值。结果与健康对照组比较,β地贫组MCV、EF明显降低,HbA2、HbF明显增高(P<0.05)。HbA2、EF、MCV、HbF的ROC曲线下面积依次为0.989、0.926、0.919、0.734,最佳cutoff值分别为3.45%、63.5%、68.25fl、0.45%,灵敏度分别为98.00%、91.10%、87.10%、77.20%;特异度分别为100.00%、81.10%、84.90%、65.10%。HbA2灵敏度和特异度最高(P<0.05)。与单项检测比较,平行联合检测明显提高诊断灵敏度,系列联合检测明显提高特异度(P<0.05)。结论以ROC曲线分析得到的MCV、EF、HbA2最佳cutoff值对β地贫杂合子筛查具有较好的诊断价值,HbA2诊断价值最高。联合检测法可提高诊断灵敏度和特异度。

Objective To explore the optimal cutoff value of mean corpuscular volume（MCV）,erythrocyte fragility（EF）,hemoglobin A2（HbA2） and hemoglobin F（HbF） by ROC curve for screening β-thalassemia（β-Thal） heterozygote.Methods Optimal cutoff values of MCV,EF,HbA2 and HbF were analyzed by ROC curve.Taking gene analysis as gold standard,the diagnostic value of single and combined detection was evaluated.Results Compared with healthy control group,MCV and EF were lower in β-Thal group,and HbA2 and HbF were higher（P0.05）.The area under ROC curve of HbA2,EF,MCV and HbF were 0.989,0.926,0.919 and 0.734,the optimal cutoff values were 3.45%,63.5%,68.25 fl and 0.45%,the sensitivity were 98.00%,91.10%,87.10% and 77.20%,and the specificity were 100.00%,81.10%,84.90% and 65.10%.The sensitivity and specificity of HbA2 were the highest（P0.05）.Compared with single test,parallel combined test could increase diagnostic sensitivity,while serial combined test could increase specificity （P0.05）.Conclusion The optimal cutoff values of MCV,EF and HbA2 might have good diagnostic application for screening β-Thal,and HbA2 could be the best.Combined detection could improve the diagnostic sensitivity and specificity.