Assessment of Hypothyroidism in Children with Beta-Thalassemia Major in North Eastern Iran

Hypothyroidism usually appears in the second decade of life and is thought to be associated with iron overload in patients with thalassemia major. This study aimed to evaluate thyroid dysfunctions in patients with beta-thalassemia major. This research is a descriptive – cross sectional study, carried out in 2009 to assess thyroid function in 100 patients with beta thalassemia major at the ages between 2-18 years. The study was carried out retrospectively and 100 medical records from 400 samples of thalassemia major patients, under regular care of Sarvar Clinic, were assessed. Thyroid function and iron load status were evaluated by measuring the serum total triiodothyronine (T4), thyroid-stimulating hormone (TSH) and ferritin levels from the serum of patients, admitted to the Sarvar Clinic. TSH and T4 concentrations were estimated by enzyme-linked immunosorbent assay (ELISA). Primary hypothyroidism was defined by a TSH level >4µIU/ml. Results were analyzed by descriptive statistical methods, with the help of SPSS software. Subclinical hypothyroidism was seen in 7% patients. All of them had normal T4 levels with elevated TSH levels, consistent with a diagnosis of subclinical hypothyroidism. Mean age of hypothyroid patients was 10.2 ± 2.5 years. Frequency of hypothyroidism was associated with increased serum ferritin levels (p=0.037). Subclinical 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.