Anti Scl 70
Antibodies to Scl-70 (anti-scleroderma antibodies with a molecular mass of 70 kD, antibodies to topoisomerase I) often appear in diffuse (40%), less often - with limited (20%) form of systemic scleroderma, CREST-syndrome. They are highly specific for scleroderma (sensitivity - 20-40%, specificity - 90-100%) and are a poor prognostic sign for the development of pulmonary fibrosis. The presence of these antibodies in systemic scleroderma in combination with HLA-DR3 / DRW52 carries a 17-fold increase in the risk of pulmonary fibrosis. The detection of Scl-70 antibodies in the blood in patients with an isolated Raynaud phenomenon indicates a high probability of systemic scleroderma.