Systemic and localized scleroderma in children.

All forms of scleroderma are rare in childhood. The most common form in childhood is localized scleroderma, which may take the form of morphea or linear scleroderma. Localized scleroderma is often benign but may cause significant deformity if it occurs on the face or extends across joint surfaces. Progressive systemic sclerosis is much less frequent in childhood but may have a rapidly progressive and ultimately fatal course. CREST (calcinosis, Raynaud's phenomenon, esophageal dysfunction, sclerodactyly, and telangieactasia) syndrome also may occur in childhood with manifestations similar to those seen in adults. In addition, some children in whom mixed connective tissue disease is initially diagnosed ultimately develop progressive systemic sclerosis. Research into both the causes and the optimal therapy for childhood scleroderma is hampered by the small number of patients treated at individual centers. This limitation has made it difficult to perform well-controlled studies.