Childhood onset systemic sclerosis: classification, clinical and serologic features, and survival in comparison with adult onset disease.

Objective: To describe the differences between patients with systemic sclerosis (SSc) having childhood versus adult onset evaluated at a single medical center.

Methods: Patients were divided into those with childhood onset (first SSc symptom or finding before age 16 yrs) and those with early adult and late adult onset. The 3 groups were compared with respect to disease classification, clinical, laboratory and serologic data, and survival.

Results: One hundred eleven childhood onset SSc cases seen between 1960 and 2003 were compared with 2559 adult onset SSc cases (1087 with onset age 16-40 and 1472 with onset after age 40 yrs) first evaluated between 1972 and 2001. Age distribution at onset was unimodal, suggesting that childhood disease is part of the spectrum of adult onset SSc. A significantly greater proportion of childhood onset patients had overlap syndromes, most frequently with polymyositis-dermatomyositis (PM-DM), and skeletal muscle involvement. Children with diffuse cutaneous (dc) SSc had significantly lower maximum mean total skin thickness scores than adult patients with dcSSc. Renal involvement was uncommon in childhood onset cases, and the frequency increased with age of onset. Serum anti-PM-Scl and anti-U1RNP antibodies were detected significantly more frequently in childhood than in adult onset cases. In contrast, anti-RNA polymerase III and anticentromere antibodies were found significantly more frequently in adults. Survival was significantly better among childhood than all adult onset cases combined, but similar to survival in young adult onset SSc cases. Scleroderma heart disease was a frequent cause of death among children with SSc.

Conclusion: Patients with juvenile onset SSc more frequently have an overlap syndrome with PM-DM, higher frequency of skeletal muscle involvement, serum anti-PM-Scl and anti-U1RNP antibody, fatal cardiac disease, and improved survival compared with adult onset SSc cases.