Antinuclear and anti-single-stranded DNA antibodies in morphea and generalized morphea

The clinical features of localized scleroderma have allowed investigators to distinguish three morphologic variants: morphea, generalized morphea, and linear scleroderma. The latter has been reported to have a higher frequency of antinuclear antibodies and has been associated with antibodies to single-stranded DNA (ssDNA). In this study we determined the frequency of antinuclear antibodies and anti-ssDNA antibodies in 22 patients with morphea or generalized morphea. None had Raynaud's phenomenon or evidence of a systemic connective-tissue disease. Antinuclear antibodies were present in 18% of patients when serum samples were tested on mouse kidney substrate but were found in 50% of HEp-2 cells. The serum samples contained anti-ssDNA antibodies in 59% of the patients, with the highest levels of ssDNA binding observed in patients with generalized morphea. The frequency of antibodies to ssDNA was higher in patients with clinical evidence of active compared with inactive disease. Discordance in immune reactivity indicates that at least three distinctive serum autoantibodies exist in morphea and generalized morphea: anti-ssDNA antibodies and antinuclear antibodies with either homogeneous or speckled immunofluorescence patterns. These findings are similar to those recently described in linear scleroderma and suggest that comparable serum autoantibody abnormalities are present in all the variants of localized scleroderma.