Childhood sclerodermatomyositis: report of a case with the anti-PM/Scl antibody and mechanic's hands.

We report a boy with overlap manifestations of systemic sclerosis and dermatomyositis (sclerodermatomyositis) whose disease showed a changing clinical pattern, and who had mechanic's hands, which are a cutaneous marker of myositis. Serological studies revealed antinuclear antibodies with a homogeneous nucleolar pattern. The anti-PM-Scl antibody was demonstrated by immunoblotting. HLA typing was positive for HLA-DR3/4. After a follow-up period of 11 years, no progression to severe systemic involvement was detected, and aggressive treatment was not administered. The recognition of subsets of patients with homogeneous clinical features and serological markers should permit the recognition of separate conditions among overlap syndromes. This would have prognostic and therapeutic implications.