What is ANTI SCL-70 ?

Evaluating patients with signs and symptoms of scleroderma and other connective tissue diseases in whom the test for antinuclear antibodies is positive

Testing for Scl 70 antibodies is not useful in patients without demonstrable antinuclear antibodies.

Testing Algorithm

See Connective Tissue Disease Cascade (CTDC) in Special Instructions.

Clinical Information

Scl 70 (topoisomerase 1) is a 100-kD nuclear and nucleolar enzyme. Scl 70 antibodies are considered to be specific for scleroderma (systemic sclerosis) and are found in up to 60% of patients with this connective tissue disease. Scl 70 antibodies are more common in patients with extensive cutaneous involvement and interstitial pulmonary fibrosis, and are considered a poor prognostic sign.