A Family Showing Resistance to Thyroid Hormone Associated with Chronic Thyroiditis and its Clinical Features: A Case Report

Abstract

Abstract. Resistance to thyroid hormone (RTH) is characterized by decreased tissue responsiveness to thyroid hormone, due mainly to mutation of the thyroid hormone receptor (TR) β gene. It has been reported that serum of patients with RTH lacks autoantibodies against thyroglobulin (Tg) and thyroid peroxidase (TPO), except in rare cases where there is cooccurrence of coincidental autoimmune thyroiditis. Here we describe the five-year medical history of a Japanese woman and her father with RTH and coincidental chronic thyroiditis. The woman, aged 28 years, was referred to our hospital because of suspected hyperthyroidism. She showed a normal level of TSH and elevated levels of free triiodothyronine (FT3) and free thyroxine (FT4). Anti-Tg and anti-TPO antibodies were slightly positive. Since RTH was suspected, her parents were investigated with informed consent. Her father showed elevated levels of TSH, FT3 and FT4, and was positive for both anti-Tg antibody and anti-TPO antibody. Her mother had hypothyroidism caused by chronic thyroiditis. Sequencing of the TR β gene showed that the patient and her father had a codon 453 mutation resulting in a CCT (proline) to ACT (threonine) substitution. The patient gradually developed emotional disturbance, and was admitted to a psychiatry ward for two months, where she was treated with lorazepam and her condition improved. Her father, on the other hand, has been doing well for five years. The patient and the father showed different clinical courses, even though they carried the same mutation of the TR β gene. The fact that the father showed an elevated TSH level, whereas the patient did not, was thought to be due to decreased thyroid function caused by chronic thyroiditis.

Resistance to Thyroid Hormone Due to a Novel Thyroid Hormone Receptor Mutant in a Patient with Hypothyroidism Secondary to Lingual Thyroid and Functional Characterization of the Mutant Receptor

“…Further, a similar adult case in which a P453T mutant TR was associated with Hashimoto disease and hypothyroidism has been reported, the serum TSH level being 140 mU/mL with 0.34 ng/dL (normal, 0.75-1.75) serum FT4 (16). In this case, replacement therapy with 100 mg/day of levothyroxine improved the symptoms of hypothyridism, suggesting that her hypothyroidism was not severe.…”

A Case of Resistance to Thyroid Hormone with Chronic Thyroiditis: Discovery of a Novel Mutation (I54V)

“…Concomitant autoimmune thyroiditis in patients with RTH is rarely reported [9, 21, 22]. As our patient was positive for anti-TPO antibodies, we diagnosed her as having RTH with coincidental autoimmune thyroiditis.…”

E449X mutation in the thyroid hormone receptor β associated with autoimmune thyroid disease and severe neuropsychomotor involvement

“…Sato and cols. (6) reported that RTH is not associated with the presence of antithyroid antibodies except in rare cases in which autoimmune thyroiditis coexists. Gavin and cols.…”

“…Sato and cols. (6) reported that patients with RTH in general have no antithyroglobulin or antithyroperoxidase antibodies, excepting rare cases in which there is coexistence of chronic autoimmune thyroiditis.…”