Clin Osteol 2025; 30(2): 82-88
Pseudohypoparathyroidism: case reportMain theme
- Osteocentrum, III. interní klinika 1. LF UK a VFN v Praze
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.
Published: June 1, 2025 Show citation
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