Overlap connective tissue syndromes.

Twenty six children with overlapping features of more than one connective tissue disorder are reported. The median age of onset was 9.5 years and median duration of follow up 7.5 years. Common presenting symptoms included arthritis, tenosynovitis. Raynaud's phenomenon, myositis, and rashes. At follow up 14 patients had developed sclerodermatous skin changes, but significant systemic involvement was uncommon. Only 16 of the 26 cases had antibodies to nuclear ribonucleoprotein; therefore, 10 did not satisfy criteria for mixed connective tissue disease. It was not possible to differentiate clinical patterns by the presence or absence of any particular antibody profile.