毛细管电泳仪检测 HbA2在珠蛋白生成障碍性贫血筛查诊断中的价值

目的：探讨全自动毛细管电泳系统检测 HbA2在珠蛋白生成障碍性贫血筛查诊断中的应用价值。方法对经基因检测确诊的249例珠蛋白生成障碍性贫血患者和142例健康体检者进行毛细管血红蛋白电泳检测。以基因检测结果将研究对象分组，比较珠蛋白生成障碍性贫血组及各亚组与健康对照组 HbA2浓度的差异性，计算毛细管电泳系统检测HbA2在不同截断值时诊断α，β及α复合β珠蛋白生成障碍性贫血的灵敏度、特异度、准确度、阳性预测值及阴性预测值。结果健康对照组 HbA2均值为（3.03±0.27）％，α珠蛋白生成障碍性贫血组 HbA2均值为（2.38±0.55）％，其中静止型、标准型及血红蛋白 H病分别为（2.61±0.46）％，（2.47±0.32）％和（1.07±0.17）％；β珠蛋白生成障碍性贫血组为（5.65±0.47）％，其中β0杂合子和β＋杂合子分别为（5.71±0.48）％和（5.56±0.43）％；α复合β型 HbA2均值为（5.7±0.82）％。与健康对照组相比，α珠蛋白生成障碍性贫血及其静止型、标准型、血红蛋白 H 病亚组 HbA2浓度明显降低（t值分别为11.73，5.02，12.91和33.46，P均＜0.01），血红蛋白 H病组较静止型和标准型 HbA2浓度明显减低（t值分别为15.62和21.31，P＜0.01），但静止型和标准型亚组之间无明显差异（t＝1.50，P＞0.05）。β珠蛋白生成障碍性贫血组及β0，β＋亚组、α复合β珠蛋白生成障碍性贫血组 HbA2浓度明显升高（t值分别为55.12，44.33，38.94和9.10，P 均＜0.01），β0，β＋亚组之间，HbA2浓度无明显差异（t＝1.79，P＞0.05）。124例β珠蛋白生成障碍性贫血，毛细管电泳系统全部检出；117例α珠蛋白生成障碍性贫血，毛细管电泳系统只检出57例。分别以2.5％，3.5％为截断值，毛细管电泳系统检测单纯α，β珠蛋白生成障碍性贫血的灵敏度、特异度、阳性预测值、阴性预测值、准确度分别为48.7

Value of Hemoglobin A2 Level Determined by Capillary Electrophoresis in Screening and Diagnosis of Thalassemia

Objective To evaluate the value of HbA2 level determined by capillary electrophoresis （Hb-CE）in screening and diagnosis of thalassemia.Methods HbA2 level of 249 thalassaemia carriers and 142 healthy controls confirmed by molecular biological detection were determined by Hb-CE method.The thalassaemia carrier subjects were divided into different groups and subgroups according to their results of gene detection.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value for the diagnosis ofα-thalassemia,β-thalassaemia,α,β-thalassaemia were calculated under different HbA2 cut-off value.Results Mean value of HbA2 in healthy controls was （3.03±0.27）%.Mean values of HbA2 inα-thalassemia group and its subgroups of silentα-thalassemia,standardα-thalassemia and hemoglobin H disease were （2.38± 0.55）%,（2.61±0.46）%,（2.47 ± 0.32）% and （1.07 ± 0.17）%,respectively.Mean values of HbA2 inβ-thalassaemia group and itsβ0 subgroup,β＋ subgroup were （5.65±0.47）%,（5.71±0.48）% and （5.56±0.43）%.Mean value of HbA2 in compoundαandβ-thalassaemia group was （5.7±0.82）%.Compared with healthy controls,HbA2 level inα-thalassemia group,silentα-thalassemia subgroup,standardα-thalassemia subgroup and hemoglobin H disease group decreased signifi-cantly （t values of 11.73,5.02,12.91 and 33.46,respectively,P〈0.01）.HbA2 level in hemaglobin H disease was signifi-cantly lower than silent and standardα-thalassemia subgroups （t values of 15.62 and 21.31,respectively,P〈0.01）,but there were no differences in HbA2 level between silent and standardα-thalassemia subgroups （t=1.50,P〉0.05）.HbA2 level inβ-thalassaemia group,β0 subgroup,β＋ subgroup and compoundαandβ-thalassaemia group increased significantly （t values of 55.12,44.33,38.94 and 9.10,respectively,P〈0.01）,but there were no differences in HbA2 level betweenβ0 andβ＋ subgroups （t=1.79,P〉0.05）.Of 249 thalassemia carriers,all 124β-thalassaemia carriers were distinguis