Antinuclear antibodies and anti-DNA antibodies in scleroderma. A possible relationship between joint manifestations and increased antibodies in localized scleroderma.

Antinuclear antibodies (ANA), including anti-DNA antibodies, and rheumatoid factors (RAT, Waaler-Rose) were determined prospectively during a 3-year period in 40 patients with localized scleroderma (LS) compared with 77 patients with generalized scleroderma (GS). ANA were increased in 26% of patients with LS, and in 47% with GS, anti-DNA antibodies in 23% of patients with LS, and in 34% with GS. Thus, the anti-DNA antibody level was lower compared with the known level in systemic lupus erythematosus. Rheumatoid factors were present in 6-7% of patients with LS, and in 14-15% of patients with GS. Increased antinuclear antibodies were not associated with any specific type of localized scleroderma, nor with internal disorders, and no case of clinical overlap to discoid or systemic lupus erythematosus was observed. However, six patients with localized scleroderma and complaints of arthralgia all presented increased antibodies, and one patient showed overlap to rheumatoid arthritis. It is suggested that increased ANA and anti-DNA antibodies in localized scleroderma, associated with joint manifestations, represents a systemic component in this type of scleroderma, with activation of the immune system and similarities with generalized collagen diseases.