Anti-topoisomerase-I and clinical findings in systemic sclerosis (scleroderma).

The relationship between anti-topoisomerase-I antibodies and clinical findings was studied in 191 patients with definite systemic sclerosis. This was done by performing ELISA to detect antibodies to recombinant topoisomerase-I. Antibodies to topoisomerase-I were found in 72 patients (37%) with systemic sclerosis, which is a higher percentage than reported in most previous reports on a large unselected population. In 43 patients the presence of antibodies to recombinant topoisomerase-I was confirmed using both the immunodiffusion method and ELISA, with similar results. When classified into diffuse versus limited disease, a significant difference in antibody prevalence was demonstrated (P < 0.005), thus indicating that anti-topoisomerase-I antibody detection with ELISA may assist in early identification of systemic sclerosis subtypes.