Abstract
Pseudohypoparathyroidism type 1A is a rare endocrine disorder caused by GNAS mutation and the resulting hormone resistance at the receptor level, i.e. the activation of the intracellular pathway of the Gs alpha subunit is not possible. This disorder is most often characterized by resistance to the parathyroid hormone. However, it can also be characterized by resistance to other hormones, such as thyroid-stimulating hormone, gonadotropins (luteinizing and follicle-stimulating hormones), growth hormone-releasing hormone, and calcitonin. In this article, we describe the case of a patient diagnosed with pseudohypoparathyroidism based on phenotypic features of hereditary Albright osteodystrophy. Due to the progressive decline in intellectual functions and changing behavior, neurological examination confirmed calcifications of the CNS as part of Fahr's syndrome. During hospitalization, higher levels of thyroid-stimulating hormone and calcitonin were observed, probably as a result of resistance at the level of the receptor and its intracellular pathway. Hypercalcitoninemia occurs sporadically in cases involving pseudohypoparathyroidism type 1-a and type 1-b. Elevated levels of calcitonin should be evaluated by means of anamnesis and clinical examination involving morphological and functional tests, considering that a highly specific tumor is a marker of medullary carcinoma of the thyroid gland, as well as some neuroendocrine tumors. Some authors recommend fine needle aspiration biopsy in order to minimize the risk of medullary thyroid cancer.
Publisher
Centre for Evaluation in Education and Science (CEON/CEES)
Reference25 articles.
1. Levine M. Hypoparathyroidism and pseudohypoparathyroidism. In: DeGroot LJ, Jameson JL, eds. Endocrinology. 5th ed. W.B. Saunders; 2005:1611-1636;
2. Mantovani G, Bastepe M, Monk D, et al. Diagnosis and management of pseudohypoparathyroidism and related disorders: first international Consensus Statement. Nat Rev Endocrinol. 2018 Aug;14(8):476-500;
3. Thiele S, Mantovani G, Barlier A, et al. From pseudohypoparathyroidism to inactivating PTH/ PTHrP signaling disorder (iPPSD), a novel classification proposed by the EuroPHP network. European Journal of Endocrinology 2016; 175(P1-P17). doi: 10.1530/EJE-16-0107;
4. Yavropoulou MP, Chronopoulos E, Trovas G, et al. Hypercalcitoninemia in pseudohypoparathyroidism type 1A and type 1B;
5. Mantovani G, Elli FM. Inactivating PTH/PTHrP Signaling Disorders. Front Horm Res. 2019;51:147-159;