Study of thyroid function in Egyptian children with β-thalassemia major and β-thalassemia intermedia

Background: thyroid dysfunction is a known complication of transfusion-dependent β-thalassemia. however,information on its frequency and risk factors among egyptian children is still unclear. objective: we aimed to determine the frequency of functional thyroid abnormalities among young patients with β-thalassemia and compare the thyroid function status among patients with β-thalassemia major (tm) and β-thalassemia intermedia (ti). materials and methods: this was a cross-sectional study that included 52 β-thalassemia children [27 boys and 25 girls; 34 (65.4%) with tm and 18 (34.6%) with ti]. their mean age was 16.0 ± 1.91 (range: 12-18) years. thyroid function and iron load status were assessed by measurement of free tetraiodothyronine,free triiodothyronine,thyroid stimulating hormone (tsh),and serum ferritin concentrations. results: serum tsh of the studied cases ranged from 0.28 to 25 μlu/ml with a mean of 4.5 ± 4.8 μlu/ml. none of the studied cases had overt primary hypothyroidism and the frequency of subclinical hypothyroidism was 19.2%. no risk factors for thyroid dysfunction could be identified among our cases. the thyroid profile was comparable in tm and ti patients (p>0.05) and the frequency of subclinical hypothyroidism among tm cases was 20.6% and it was comparable to the 16.7% found among ti patients (p>0.05). no correlations were found between tsh,serum ferritin,chelation therapy,and frequency of blood transfusion. conclusion and recommendations: both tm and ti patients are at risk for subclinical thyroid failure regardless of their iron overload status. early evaluation of thyroid function in β-thalassemia children and thyroid replacement therapy for subclinical hypothyroidism should be introduced in the treatment protocols. © 2013 egyptian public health association.