Pseudohypoparathyroidism

Pseudohypoparathyroidism is end-organ resistance to parathyroid hormone (PTH), causing hypocalcemia and hyperphosphatemia despite elevated PTH (Albright hereditary osteodystrophy). Phenotype: short stature, round face, obesity, short 4th/5th metacarpals (knuckle sign), subcutaneous calcifications, and variable intellectual impairment. Caused by GNAS gene inactivation. Treatment: calcium and active vitamin D (calcitriol) supplementation.

Common Symptoms

Tetany; hypocalcemia; hyperphosphatemia; short stature; round face; short 4th/5th metacarpals; subcutaneous calcification

Causes and Pathogenesis

GNAS-inactivating mutation impairs PTH-receptor-coupled cAMP generation in kidney/bone, causing renal phosphate retention and impaired calcium mobilization despite high PTH.

Treatment

Oral calcium supplementation; calcitriol (active vitamin D); monitor calcium/phosphate; treat hypocalcemic tetany acutely

Preventive Measures

Genetic counseling; family screening; maintain calcium/vitamin D intake.

Department to Visit

It is recommended to visit the Endocrinology department; an appointment can be booked on this platform before the visit.

Warm reminder: The above information is for health science reference only and cannot replace professional medical diagnosis. If you have related symptoms, please seek medical attention at a regular hospital promptly.