The concentration of serum sex hormone-binding globulin is increased in hyperthyroid states such as TSH-secreting pituitary tumors, whereas normal concentrations of this globulin are expected in patients with resistance to thyroid hormone (5).
Resistance to thyroid hormone lacks specific clinical manifestations.
Mice with a targeted mutation in the thyroid hormone beta receptor gene exhibit impaired growth and resistance to thyroid hormone
In these cases, there is partial resistance to thyroid hormone and as the patients are clinically euthyroid, there is no need for treatment (7), (9).
Resistance to thyroid hormone in a Chinese Family with R429Q mutation in the thyroid hormone receptor beta gene.
Brucker-Davis F, Skarulis MC, Grace MB, et al: Genetic and clinical features of 42 kindreds with resistance to thyroid hormone.
Homozygosity for a "dominant negative" tyroid hormone receptor gene responsible for generalized resistance to thyroid hormone.
Attention deficit-hyperactivity disorder in people with generalized resistance to thyroid hormone
Mosaicism of a Thyroid Hormone Receptor (TR) Beta Gene Mutation in Resistance to Thyroid Hormone
TSH below normal TSH above normal Primary hyperthyroidism Primary hypothyroidism Pituitary/hypothalamic disease Pituitary thyrotroph adenoma with central hypothyroidism Pituitary resistance to thyroid hormone
(central hyperthyroidism) Generalized thyroid hormone resistance Prolonged thyrotroph cell Thyrotoxicosis from overly rapid suppression after recent correction of severe hypothyroidism hyperthyroidism in euthyroid with parenteral [T.
There is also good evidence that leptin stimulates autoimmune processes, decreases TRH gene expression in the hypothalamus and TRH synthesis, enhances the resistance to thyroid hormones
and thus leads to hypothyroidism and starts the vicious circle of obesity and HT [24-26].