血常规、血清铁及血红蛋白电泳联合检测在地中海贫血非高发地区的筛查意义

OBJECTIVE: To evaluate the role of combined detections of routine blood test, serum iron and hemoglobin electrophoresis in screening thalassemia in non-high incidence area. METHODS: Peripheral blood and serum samples of 1 000 outpatients from the department of hematology and the department of gynecology and obstetrics were obtained. Common mutations of thalassemia were detected by using GAP-PCR and reverse dot blotting, and Sanger sequencing was performed to discover rare mutations of α-and β-thalassemia. Routine blood test, serum iron and hemoglobin electrophoresis were also performed for every patient. RESULTS: Among 1 000 samples, 225(22.5%) are detected as α-thalassemia, 403(40.3%) β-thalassemia and 15(1.5%) composite thalassemia. Among 225 α-thalassemia patients, 28 were silent, 138 were intermedia, and 59 were HbH disease. Of 403 β-thalassemia, 390 were carriers, 7 were double heterozygote, and 6 were homozygote. In all samples, there were 357 patients detected with no common mutations, 38 patients had higher result values for both MCV and MCH and none detected with thalassemia gene. There were 48 patients who had higher serum iron but normal or lower MCV, 42 of them (87.5%) had thalassemia gene. Furthermore, 38 patients showed abnormal hemoglobin electrophoresis, 35 of them were HbH disease, while the other 3 were HbF-related thalassemia. Five patients showed abnormal hemoglobin electrophoresis, lower MCV and MCH, as well as higher serum iron, had no frequent mutation but rare ones. CONCLUSION: Patients with higher MCV and MCH can mostly be excluded to have thalassemia, while higher serum iron represents thalassemia possibility and can provide a preliminary indication of thalassemia type, and last but not least abnormal hemoglobin electrophoresis indicates the disease. It is recommended to further carry out sequencing of rare mutations for those who had abnormal results in the combined screening, and detected with no frequent mutation. Combination of these three examinations can improve the detection efficiency of patients with thalassemia.