Guest Editor: Raffaella Origa THYROID DISORDERS IN HOMOZYGOUS β-THALASSEMIA: CURRENT KNOWLEDGE, EMERGING ISSUES AND OPEN PROBLEMS

Abstract.Changes in thyroid function and thyroid function tests occur in patients with β-thalassemia major (TM). The frequency of hypothyroidism in TM patients ranges from 4% to 29 % in different reports. The wide variation has been attributed to several factors such as patients ' genotype, age, ethnic variations, treatment protocols of transfusions and chelation, and varying compliance to treatment. Hypothyroidism is the result of primary gland failure or insufficient thy ­roid gland stimulation by the hypothalamus or pituitary gland. The main laboratory parameters of thyroid function are the assessments of serum thyroid-stimulating hor­mone (TSH) and serum free thyroxine (FT4). It is of primary importance to interpret these measure­ments within the context of the laboratory-specific normative range for each test. An ele­vated serum TSH level with a normal range of serum FT4 level is consistent with subclinical hypothyroidism. A low serum FT4 level with a low, or inappropriately normal, serum TSH level is consistent with secondary hypothyroidism. Doctors ca ring for TM patients most commonly encounter subjects with subclinical primary hypothy­roidism in the second decade of life. Several aspects remain to be elucidated as the frequency of thyroid cancer and the possible existence of a relationship between thyroid dysfunction on one hand, cardiovascula r diseases, components of metabolic syndrome (insulin resistance) and hypercoagulable state on the other hand. Further ...
Source: Mediterranean Journal of Hematology and Infectious Diseases - Category: Hematology Source Type: research