Clin Osteol 2025; 30(2): 82-88
Pseudohypoparatyreóza: kazuistikaHlavní téma
- Osteocentrum, III. interní klinika 1. LF UK a VFN v Praze
Pseudohypoparatyreóza (PHP) je vzácné metabolické onemocnění charakterizované biochemickými známkami hypoparatyreózy (hypokalcemií a hyperfosfatemií), zvýšenou sekrecí parathormonu (PTH) a necitlivostí cílových tkání k biologickému působení PTH. PHP je způsobena genetickými nebo epigenetickými abnormalitami v GNAS (gen kódující alfa-podjednotku stimulačního G proteinu) a je klasifikována jako PHP1A nebo PHP1B v závislosti na místě genetické mutace. V naší kazuistice publikujeme případ 31letého muže s pseudohypoparatyreózou typu 1B (PHP1B), která byla náhodně diagnostikována po úrazu hlavy. Pacient neměl známky Albrightovy hereditární osteodystrofie (AHO), ani jiná přidružená onemocnění spojená s PHP. Genetické vyšetření prokázalo deleci exonů 5-7 genu STX16 a ztrátu metylace GNAS A/B.
Klíčová slova: pseudohypoparatyreóza, hypokalcemie, GNAS.
Pseudohypoparathyroidism: case report
Pseudohypoparathyroidism (PHP) is a rare metabolic disorder characterized by biochemical signs of hypoparathyroidism (hypocalcemia and hyperphosphatemia), increased secretion of parathyroid hormone (PTH), and resistance in target tissues to the biological action of PTH. PHP is caused by genetic or epigenetic abnormalities in the guanine nucleotide-binding protein alpha-stimulating gene (GNAS) and is classified as PHP1A or PHP1B, depending on the site of the genetic abnormality. In our case report, we publish the case of a 31-year-old man with PHP type 1B, which was diagnosed accidentally after a head injury. The patient did not have Albright hereditary osteodystrophy (AHO) or other comorbidities. Genetic examination revealed deletion of exons 5-7 in the STX16 gene and loss of methylation at GNAS A/B.
Keywords: pseudohypoparathyroidism, hypocalcemia, GNAS.
Zveřejněno: 1. červen 2025 Zobrazit citaci
Reference
- Levine MA, Downs RW, Singer M, et al. Deficient activity of guanine nucleotide regulatory protein in erythrocytes from patients with pseudohypoparathyroidism. Biochem Biophys Res Commun. 1980;94:1319-1324.
- Farfel Z, Brickman AS, Kaslow HR, et al. Defect of receptor-cyclase coupling protein in pseudohypoparathyroidism. N Engl J Med. 1980;303:237-242.
- Mantovani G, Bastepe M, Monk D, et al. Diagnosis and management of pseudohypoparathyroidism and relevant disorders: first international Consensus Statement. Nat Rev Endocrinol. 2018;14(8):476-500.
- Linglart A, Levine M, Harald J. Pseudohypoparathyroidism. Endocrinol Metab Clin North Am. 2018;47(4):865-888.
- Michot C, Le Goff C, Goldenberg A, et al. Exome sequencing identifies PDE4D mutations as another cause of acrodysostosis. Am J Hum Genet. 2012;90(4):740-5.
- Linglart A, Menguy C, Convineau A, et al. Recurrent PRKAR1A mutation in acrodysostosis with hormone resistance. N Engl J Med. 2011;364(23):2218-2226.
- Thiele S, Mantovani G, Bartolier A, et al. From pseudohypoparathyroidism to inactivating PTH/PTHrP signalling disorder (iPPSD), a novel classification proposed by the EuroPHP network. Eur J Endocrinol. 2016;175(6):1-17.
- de Lange IM, Verrijn Stuart AA, van der Luijt C, et al. Macrosomia, obesity and macrocephaly as first clinical presentation of PTH1b caused by STX16 deletion. Am J Med Genet A. 2016;170:2431-2435.
- Molinaro A, et al. TSH elevation as the first laboratory evidence for pseudohypoparathyroidism type 1 b (PHP-1 b). J Bone Miner Res. 2015;30:906-912.
- Mantovani G, et al. Pseudohypoparathyroidism and GNAS epigenetic defects: clinical evaluation of Albright hereditary osteodystrophy and molecular analysis in 40 patients. J Clin Endocrinol Metab. 2010;95:651-658.