ESPE Abstracts

Background: Pseudohypoparathyroidism (Albright hereditary osteodystrophy (AHO)) is a rare congenital disorder mainly affecting bone and thyroid metabolism as a result of resistance of parathyroid hormone (PTH) and thyrotropin (TSH), gonadotropins, growth hormone-releasing hormone (GHRH) and calcitonin in the target tissues. According to the consensus statement "Diagnosis and management of pseudohypoparathyroidism and related disorders" published in 2018, the specific diagnosis is often delayed owing to lack of recognition of the syndrome and associated features.

Case presentations: A two year old boy was seen with early onset obesity and motor delay. At the abdominal skin lividly discoloured lesions were seen. Another unrelated eight months old boy presented since the age of five months with early onset obesity, intracutaneous calcifications and mild motor delay. In both children we found high parathyroid hormone serum levels (442 pg/mL and 88 pg/mL, normal range: 11-67 pg/mL) in combination with elevated levels of TSH. In both patients sequencing revealed a heterozygous mutation c.565_568delGACT; p.ASP189Metf*14 in the GNAS gene. This particular mutation has already been described and confirmed the diagnosis AHO. Levothyroxine and calcitriol treatment as well as physiotherapy were immediately started.

Conclusion: Subcutaneous ossifications combined with motor delay and early onset obesity may often be the single clinical signs of pseudohypoparathyroidism. Paediatric endocrinologists should therefore advice their paediatric colleagues about this syndrome and its clinical picture and motivate them to transfer these patients to a paediatric endocrine centre for further management.