[Diagnostic Value of HBA₂ in Different Types of Thalassemia]

To explore the diagnostic value of HBA₂ in different types of thalassemia by analyzing the sensitivity and missed diagnosis rate of HBA₂ in different types of thalassemia.

1 178 couples in the department of women's health of Chongqing maternal and child health hospital were selected for pregnancy examination. Peripheral venous blood was extracted and analyzed for parallel blood routine test, hemoglobin capillary electrophoresis and thalassemia gene detection.

A total of 265 cases of thalassemia gene carriers were screened out in 1 178 couples； 91.3% β⁰ heterozygous thalassemia and 94.74% β⁺ heterozygous thalassemia could be screened out using HBA₂ > 3.5% as cut-off value; 30.19% stationary α-thalassemia and 66.07% standard α-thalassemia could be screened out using HBA₂ < 2.5% as cut-off value. The rate of missed diagnosis of α-thalassemia and β-thalassemia was 47% and 1.01% respectively when the blood routine screening is positive.

HBA₂ shows different diagnostic value for different types of α-thalassemia and β-thalassemia. The sensitivity of HBA₂ > 3.5% is higher than that of HBA₂ < 2.5%. More attention should be paid to the further screening of patients with normal electrophoresis results when the blood routine screening is positive.