Over the course of past 2 to 3 decades, hypertransfusion therapy and chelation therapy have significantly increased the life expectancy and improved the life quality of patients with thalassaemia major (TM). Neverthless, even in carefully managed patients endocrine disturbances may develop. Stunted growth, delayed puberty/hypogonadism, hypothyroidism, hypoparathyroidism and diabetes mellitus are well-recognized complications of iron overload. As the symptoms of hypothyroidism are non-specific, but the consequences affect virtually every organ system, an early systematic laboratory evaluation and control of thyroid function is recommended in all TM patients, annually. Different studies have revealed that several changes in thyroid hormone concentrations may occur with a wide spectrum of severity varying from sub-biochemical hypothyroidism to overt hypothyroidism. Central hypothyroidism is an uncommon clinical entity and its prevalence at different ages is unknown. Thyroid failure is expected to be more prevalent in older patients although in developing countries it may occur at younger age. The occurrence of malignancies in TM patients is an emerging concern for physicians. Recently, we observed three female TM patients with incidental papillary thyroid microcarcinoma. Overt hypothyroidism is classically treated by oral replacement with synthetic L-thyroxine. A close monitoring of TSH is recommended in hypothyroid TM patients with cardiac dysfunction and osteoporosis, as over-replacement with L-T4 may cause dysrhythmias and accelerated bone loss. In sub-clinical hypothyroidism the decision to treat depends on each individual case. In this review, we will highlight some recent aspects of diagnosis and treatment of thyroid disorders in patients with β-thalassaemia major.
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