赣州地区地中海贫血基因型特点及筛查项目评价

摘要

目的 以红细胞参数(MCV、MCH、MCH)联合血清铁蛋白(SF)作为筛查指标,结合基因检测,了解赣州地区地中海贫血(地贫)患者的基因类型,评价各项筛查指标的敏感性及特异性.方法 选择疑似地贫911例,进行血细胞分析、SF检测、地贫基因检测,统计分析地贫患者基因型分布,比较红细胞各参数、SF在地贫筛查中的敏感性及特异性.结果 911例受检者中检测出地贫549例,检出率60.26％,α复合β地贫19例,α-地贫322例,共14种α-地贫基因型,前3种分别是:--SEA/αα(178例,32.42％),--SEA/-α3.7(49例,8.93％),--SEA/-α4.2(34例,6.19％).检出β-地贫208例,共12种β-地贫基因型,前3种分别是:IVS-Ⅱ-654(C＞ T)/N(94例,17.12％),CD41-42(-TFCT)/N(71例,12.93％),CDl7(A＞T)/N(13例,2.37％).MCV、MCH、MCV+ MCH在筛查中敏感性高,分别为94.07％、96.05％、93.5％,显著高于MCHC、MCV+ SF、MCH+ SF、MCHC+ SF(P＜0.05),MCV+SF、MCHC+ SF特异性为94.12％,高于MCH、MCV+ MCH(P＜0.05),不高于MCV、MCHC、MCH+ SF,地贫合并缺铁性贫血(IDA)的患者的MCV低于单纯IDA,MCV、MCH、MCHC低于单纯地贫患者(P＜0.05).地贫合并IDA、单纯IDA患者的SF低于单纯地贫患者(P＜0.05).结论 赣州地区客家人地贫基因类型具有区域特点,筛查的实验室指标可采用敏感性高的指标MCV和(或)MCH,采用MCV+ SF、MCH+SF筛查,特异性高达94.12％、88.24％;当IDA患者有家族性红细胞参数异常或疗效不理想时,有合并地贫可能,应该进行地贫基因检测,以免漏诊.%Objective To investigate the genotypes of thalassemia and assess sensitivity and specificity of screening project on thalassemia by erythrocyte indices,serum ferritin (SF) and gene detection among population in Ganzhou,Jiangxi.Methods From January 2013 to August 2016,911 subjects underwent thalassemia screening at the Department of Hematology of the First Affiliated Hospital of Gannan Medical University were included.Genotypes of thalassemia were analyzed,and RBC parameters and serum ferritin (SF) were calculated in Hakka population with thalassemia.The diagnostic evaluation on RBC parameters and serum ferritin (SF) for simple thalassemia,thalassemia associated with iron deficiency anemia (IDA) and simple IDA were performed in Hakka population.Results Fourteen genotypes of α-thalassemia were identified in 911 participants,and the most common genotypes were--SEA/αα (178 cases,32.42％),--SEA/-α3.7 (49 cases,8.93％) and--SEA/-α4.2 (34 cases,6.19％).Twelve genotypes of β-thalassemia were found,and the most common genotypes were IVS-Ⅱ-654 (C ＞ T)/N (94 cases,17.12％) and CD41-42 (-TTCT)/N (71 cases,12.93％) and CDl7(A ＞T)/N(13 cases,2.37％).The sensitivity of MCV,MCH and MCV plus MCH,which were 94.07％,96.05％,93.5％,were higher than MCHC,MCV plus SF,MCH plus SF and MCHC plus SF(P ＜0.05).The specificity of MCV plus SF and MCHC plus SF were 94.12％ and higher than MCH and MCV plus MCH(P ＜0.05).There was no difference between MCV plus SF,MCHC plus SF and MCV,MCHC,MCH plus SF in specificity.MCV in patients with thalassemia associated with IDA was lower than in those with simple IDA.MCV,MCH and MCHC in patients with thalassemia associated with IDA were lower than in those with simple thalassemia.SF in Patients with thalassemia associated with IDA and simple IDA patients were lower than in those with simple thalassemia (P ＜ 0.05).Conclusion Genotype of thalassemia in Hakka population in Ganzhou was local characteristics.MCV or MCH which are high sensitivity can be selected in screening thalassemia in high incidence area.The specificity of MCV or MCH combination with SF can be up to 94.12％,88.24％,respectively.When IDA patients,erythrocyte indices are abnormal in familial aggregation or curative effect is poor,they may be the patients with IDA and thalassemia.Therefore they should get tested genetically in case of misdiagnosis.