How do you approach an isolated positive anti-Scl-70 antibody in a patient with no symptoms or exam findings suggestive of systemic sclerosis?

We see this often in the clinic, and it is usually a false-positive test. False-positive anti-topoisomerase I (Scl-70) results frequently occur with commercial immunoassays (ELISA/Multiplex), often leading to misdiagnosis of systemic sclerosis. In our practice, we repeat the test using immunodiffusi...