Frequency of hypothyroidism in patients of β-thalassaemia

Objective: to determine the frequency of hypothyroidism in patients suffering from homozygous β-thalassaemia. methods: this descriptive study included 70 diagnosed thalassaemia major patients aged 5-14 years. demographic data as well as history of blood transfusion and chelation therapy was collected. random blood samples were drawn and thyroid profile (serum thyroxine [t4], triiodothyronine [t3] and thyroid stimulating hormone concentrations [tsh]) was done by enzyme-linked immunosorbent assay (elisa). primary hypothyroidism was defined by a tsh level >4μiu/ml. results were analysed by descriptive statistical methods. results: primary hypothyroidism was seen in 18 (25.7%) patients. of these, 17 had normal t4 levels with elevated tsh levels consistent with a diagnosis of compensated primary hypothyroidism whereas only one patient showed a decreased t4 level with elevated tsh (uncompensated primary hypothyroidism). mean age of hypothyroid patients was 9.2 ± 2.6 years. frequency of hypothyroidism was associated with increased serum ferritin levels. conclusion: primary hypothyroidism occurs in a significant proportion of thalassaemia major patients in the absence of obvious clinical signs of hypothyroidism. regular follow-up for early detection and timely treatment of such complications could improve the quality of life of these patients.