Study For The Genotypes And Phenotypes Of Beta-Thalassemia Intermedia In Western Of Guangxi

Objective To provide the basis of treatments, genetic counseling and prenatal diagnoses for beta-thalassemia intermedia (TI), we studied the characteristics of its clinical phenotypes and genotypes in the west of Guangxi, China.Methods The clinical phenotypes, complications and laboratory tests (Including Erythrocyte indices, serum ferritin, Hemoglobin Electrophoresis,β-thalassemia genes andα-thalassemia genes, etc) of 56 TI patients were analyzed, who were hospitalized to our hospital and genetic counseling clinic from January, 2005, to September, 2009.Results 1. Clinical phenotypes: 56 TI patients were enrolled to the study. 25(44.6%) patients had an earlier age of onset (before two years). Infection (32.1%), anemia (30.4%) and jaundice (14.3%) were the top three causes why patients went to the hospital for their first visit. Most patients had thalassemia-like appearance (66.1%), hepatomegaly (66.1%), splenomegaly (76.8%), transfusion (78.6%) and an enlarged heart (51.8%). 7(12.5%) patients were underweight. 4(7.1%) some had stunted growth. 3(5.4%) some had received a splenectomy. The patients had multi-system complications (including hypersplenism, gallstones, kidney stones, hepatitis B, diabetes and so on), which were more common in adults and older children. The values of Hb, MCV, MCH of 56 cases in hospital were (64.6±17.5) g/L, (63.1±10.0)fL,(19.5±3.2)pg respectively. There were 73.3% (22/30) cases with SF (698.5 L±516.3)μg/L, which was higher than the reference value. 21 cases were HbE/βgenotype,of which HbF and HbE were(39.5±18.7)% and(55.7±15.3)% respectively. While the HbF of the other cases with different genotypes were(74.2±30.8)%. 2. Genotypes: there were 38 out of 56 cases for which genotyping were carried out. 22 of these 38 cases had kinds of genotypes detected which had the genotype characteristics of west Guangxi. Five of them were respectively twoβ0/β+ combined with --SEA/αα, oneβ+/β+, oneβ0/HbE combined with -α4.2/ααand oneβ0/HbE combined with --SEA/αα, which manifested typical TI. Sixβ0/β+, oneβ0/β+ combined with -α3.7/ααand oneβ0/β0 combined with -α4.2/ααshowed more serious TI. In 13 cases ofβ0/HbE, 6 patients performed more serious TI, while 7 patients manifested typical TI. In 10 cases ofβ0/β0 combined with --SEA/αα, seven patients revealed more serious TI, while three patients manifested typical TI. In two cases ofβ0/β0, one revealed milder TI, while the other manifested typical TI.Conclusion We first described the characteristics of genotypes and clinical phenotypes with beta-thalassemia intermedia in the west of Guangxi. The patients in this area had early onset, a wider spectrum of clinical phenotypes and multi-system complications, whose genotypes showed heterogeneity with its own characteristics.