Pseudohypoparathyroidism secondary to Albright’s hereditary osteodystrophy: a case report

*Correspondence: [e-mail].

Abstract

Case Presentation: A 6-year-old boy, born small for gestational age, with previous history of neurodevelopmental delay and congenital hypothyroidism, presented he first seizure described as ocular elevation and global hypotony during sleep with duration of five minutes and followed by drowsiness. At admission, we noted brachydactyly, short stature, short neck and round face. Neurological examination revealed difficulty to obey complex commands, language delay and a wide-based gait. Complementary investigation identified hypocalcemia (ionized calcium: 0.74 mmol/L and total calcium: 6.3 mmol/L), hyperphosphatemia (9.4 mmol/L) and high level of parathyroid hormone (394 pg/mL) with normal renal function (creatinine: 0.4 mg/dL and urea: 28 mg/dL). Magnetic resonance imaging of the brain showed bilaterally and symmetrically foci of hyper sign in regions of cortical-subcortical transition involving infratentorial and supratentorial white matter and the basal ganglia, possibly representing calcifications. Long bones xray presented osteopenia and signs of cortical thinning. After a discussion between neuropediatric and endocrinopediatric teams, the hypothesis was pseudohypoparathyroidism secondary to Albright’s Hereditary Osteodystrophy (AHO), confirmed with genetic test that evidenced a variant pathogenic in the GNAS gene.

Discussion: The first description of Albright Hereditary Osteodystrophy dates from 1942, but so far there is no dates about prevalence, and it is probable underestimated. This syndrome includes a constellation of signs, in addition to those presented in our patient, obesity, subcutaneous ossifications, dental abnormalities, cataract, cognitive impairment and pubertal delay are common. Seizures, cramps and spasms occur because hypocalcemia secondary to elevated parathyroid hormone.

Final Comments: The path to diagnose AHO emphasizes the importance of a broader view of the patient, which should go beyond neurological manifestations, providing early detection of this rare, and probably underestimated, syndrome and consequently enable adequate management of the various manifestations of the disease.

Publication History

Article published online:
12 May 2025