Calcinosis Cutis

Excerpt

Calcinosis cutis is a condition in which calcium salts are deposited in the skin and subcutaneous tissue. It is classified into five main types: dystrophic, metastatic, idiopathic, iatrogenic, and calciphylaxis. Dystrophic calcification is the most common cause of calcinosis cutis and is associated with normal laboratory values of calcium and phosphorus. There is an underlying disease, systemic sclerosis, dermatomyositis, mixed connective tissue disease, or lupus, that induces tissue damage and creates a nidus for calcification. Metastatic calcification has abnormal serum levels of calcium and phosphorus with deposition occurring after calcium phosphate product exceeds 70. Idiopathic calcification has no underlying tissue damage or abnormal laboratory values. It includes tumoral calcinosis, subepidermal calcified nodules, and scrotal calcinosis. Iatrogenic calcification is caused by administration of calcium or phosphate containing agent and inducing precipitation of calcium salts. Calciphylaxis involves calcification of small and medium-sized vessels and is associated with chronic renal failure and dialysis. The disorder is classified as calcinosis circumscripta if it is limited to an extremity or joint. Calcinosis universalis occurs when there is diffuse involvement of subcutaneous and fibrous structures of muscles and tendons.