Endocrine Abstracts

Introduction: Pseudohypoparathyroidism (PHP) is a part of a very rare heterogeneous group of endocrine disorders. It is caused by alterations in the PTH receptor, which is encoded by the GNAS1 gene inducing target tissue resistance to PTH. Pseudohypoparathyroidism typically gets discovered during early childhood, rare are the cases discovered in adulthood.

Observation: Herein the case of a 35-year-old man, descendant of a non-consanguineous marriage, with a medical history of bilateral cataract surgery at the age of 33 years-old, who consulted the emergency department for an epileptic seizure then he was transferred after discovering a severe hypocalcemia with Fahr’s syndrome at the CT-Scan.The patient didn’t present neither cramps or paresthesia. Chvostek and Trousseau signs were negative. He had a short stature (Height 153 cm vs Target height 180 cm), dental hypoplasia and soft tissue calcifications on the dorsal part of the hands confirmed by the X-Ray imaging. The patient was in sinus tachycardia at 115 bpm with a non-prolonged corrected QT interval (353 ms). The biology showed a low corrected calcium level at 1.94 mmol/l, an elevated level of phosphorus (1.89 mmol/l), a high level of PTH (170 pg/ml) and a normal renal function (creatinine 60μmol/l), in favor of the diagnosis of PHP. The patient was treated with the association of calcium (6g/day) and alphacalcidol (2μg/day), and the corrected calcium level when he was discharged was at 2.14 mmol/l.

Conclusion: In PHP the target tissue is resistant to PTH, resulting in hypocalcemia and hyperphosphatemia. Five different types of PHP, each with specific features, have been described. The best-known type of PHP is type 1a, where biochemical disruptions are combined with a phenotype called Albright’s hereditary osteodystrophy (AHO), including short stature, round face, brachymetacarpia, and subcutaneous ossifications. But the diagnosis of certainty in our case remains genetic.