Albright's Hereditary Osteodystrophy With Cutaneous Bone Formation

Abstract

Albright's hereditary osteodystrophy (AHO) refers to the syndromes of pseudohypoparathyroidism (PHP) and pseudopseudohypoparathyroidism (PPHP). Both PHP and PPHP have the same phenotype, but PHP patients have hypocalcemia and fail to respond to parathyroid hormone. The PPHP patients have normal serum calcium values. Cases have been observed to change, over a period of time, from PHP to PPHP. This case of PHP demonstrates intracutaneous lamellar bone formation. The patient with AHO is short with shortened metacarpals and metatarsals, round facies, short broad nails, and soft tissue calcifications. They may also have cataracts, basal ganglia calcification, mental retardation, defective teeth, and multiple other skeletal abnormalities. There may also be tetany or muscle cramps. The mode of inheritance is unclear and may be sex-linked dominant. Differential diagnosis includes hypoparathyroidism, basal cell nevus syndrome, Gardner's syndrome, and sex-chromatinnegative Turner's syndrome.