Increased frequency of DR4 in systemic onset juvenile chronic arthritis.

Eighty-one patients with systemic onset juvenile chronic arthritis (JCA) have been tested for HLA-A, -B, -C, and -DR antigens. This study confirms previous reports of an increased incidence of DR4 in these patients. Subdivision of the patients according to their disease course over ten years showed different HLA associations with different disease courses. The frequency of DR4 tended to be greater in patients with less severe disease. There was also an increased incidence of HLA B27 in patients in whom relapses of disease were associated with intercurrent infections.