Linear skin atrophy preceding calcinosis cutis in pseudo-pseudohypoparathyroidism

Albright hereditary osteodystrophy (AHO) is a syndrome caused by inactivating mutations in the GNAS (guanine nucleotide-binding protein, alpha-stimulating) gene. Patients with AHO have short stature, obesity, brachydactyly and subcutaneous calcifications. AHO can be associated with pseudohypoparathyroidism type IA (PHP-IA) with upregulation of parathyroid hormone, whereas in pseudo-pseudohypoparathyroidism (PPHP), an endocrinopathy is not present. We report the case of a 5-month-old male infant who presented with slowly progressive linear atrophic skin lesions. The histological findings showed evidence of dermal hypoplasia. The child's father had PHP-IA. Four months after presentation, the infant developed calcifications within the pre-existent atrophic lesions. No alterations in calcium metabolism were noted. Analysis of the GNAS gene identified a short duplication leading to a frameshift mutation. We conclude that linear atrophic skin lesions may be an early sign of imminent cutaneous calcifications in AHO.