Clinical Vignette Pseudopseudohypoparathyroidism, Presenting with Osteoma Cutis

• Published in: Journal of bone and mineral research 1997-06, Vol.12 (6), p.995-995
• Main Authors: Lucky, Anne W., Tsang, Reginald
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Endocrinopathies; Medical sciences; Non tumoral diseases. Target tissue resistance. Benign neoplasms; Parathyroids. Parafollicular cells. Cholecalciferol. Phosphocalcic homeostasis (diseases)
• ISSN: 0884-0431; 1523-4681
• DOI: 10.1359/jbmr.1997.12.6.995

A 10-month-old girl was seen by the dermatologist for evaluation of "marks" on her abdomen. Her parents thought that they had been there since birth or very early infancy. Pseudohypoparathyroidism presents in childhood typically with hypocalcemic tetany, hyperphosphatemia, and elevated serum PTH. The usual phenotype is a short individual with "stubby" hands often with dimples on the dorsi of the hands. Often firm violaceus intradermal lesions appear over the body and have been reported to migrate. X-rays of the hands show shortened metacarpals. Although termed "calcinosis cutis," most if not all of these nodules represent osteoma cutis or new bone formation in the dermis. Skin biopsy reveals heterotopic ossification. There may be a preclinical phase, i.e., phenotype without biochemical changes, or pseudopseudohypopar athyroidis. Identification of such infants prior to overt biochemical changes can allow a lifetime of normal serum calcium concentrations if these infants are followed every 3 months to detect early hypocalcemia.