Endocrine Abstracts

This case reports describes a 26-year-old presented with having regular shakes, including tremulous arms, feeling hot and cold, mood swings, increased sweating, constantly feeling hungry, being itching all the time and having stomach-ache. She felt easily bloated with certain types of food. She was investigated and found to have thyroid hormone dysfunction. Symptoms were suggestive of Thyrotoxicosis with Biochemical evidence of Thyrotoxicosis. She had further investigations including genetic studies which confirmed resistance to thyroid hormone. TSH Secreting adenoma is a differential but due pattern of inheritance with positive family history in the first degree relative (father RTH) investigations to differentiate between the two won’t be needed and genetic test could be more cost effective. TSH 1.1 mU/l(0.30-6.00) Normal since 2011 FreeT4 26.6 pmol/l(10.4-24.5) Fluctuating between high and normal since 2011 but persistent High Since 2021 FreeT3 6.2 pmol/l(3.0-7.1) but in 2020 high twice 7.8 & 7.6 pmol/lCRP <5 ESR 5 mm/hr Genetic Testing: heterozygous familial THRB pathogenic variant RTH is autosomal dominant defect in 1 of the 2-thyroid hormone receptors, resulting in decreased end organ responsiveness/sensitivity to thyroid hormones. THR can be classified based on tissue resistance into pituitary, peripheral or generalized (both pituitary and peripheral) types. Mutations in the TR-beta gene, cell membrane transporter and genes controlling intracellular metabolism of thyroid hormone have been implicated in 85% of cases. It is characterized by elevated Thyroid Hormone Levels but the thyroid stimulating hormone (TSH) level is not suppressed, or not completely suppressed as would be expected. Many a times RTH can be mismanaged as hyper/hypothyroidism or there can be a delay in diagnosis due to lack of proper history and investigations. The diagnosis helps in appropriate treatment approach for the patient and genetic counselling of the family.