1. Hypothyroidism Associated to TSH Hormone-Receptor Autoantibodies with Blocking Activity Assessed In Vitro
- Author
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Pedro Marques, Chikh K, Charrié A, Pina R, Mj, Bugalho, and Lopes L
- Subjects
endocrine system ,Tireoidite Autoimune ,HDE END PED ,endocrine system diseases ,Receptores da Tireotropina ,Hipotiroidismo ,Doença de Graves ,Criança ,Caso Clínico - Abstract
Thyroid-stimulating hormone-receptor autoantibodies normally causes hyperthyroidism. However, they might have blocking activity causing hypothyroidism. A 11-year-old girl followed due to type 1 diabetes mellitus, celiac disease and euthyroid lymphocytic thyroiditis at diagnosis. Two years after the initial evaluation, thyroid-stimulating hormone was suppressed with normal free T4; nine months later, a biochemical evolution to hypothyroidism with thyroid-stimulating hormone-receptor autoantibodies elevation was seen; the patient remained always asymptomatic. Chinese hamster ovary cells were transfected with the recombinant human thyroid-stimulating hormone -receptor, and then exposed to the patient's serum; it was estimated a 'moderate' blocking activity of these thyroid-stimulating hormone-receptor autoantibodies, and concomitantly excluded stimulating action. In this case, the acknowledgment of the blocking activity of the serum thyroid-stimulating hormone-receptor autoantibodies, supported the hypothesis of a multifactorial aetiology of the hypothyroidism, which in the absence of the in vitro tests, we would consider only as a consequence of the destructive process associated to lymphocytic thyroiditis.
- Published
- 2015