[Anti-DFS70: significance and clinical utility of a new anti-nuclear antibody]

When screening anti-nuclear antibodies (ANAs) by immunofluorescence, a positive result is often found in subjects without proven autoimmune pathologies. The observed pattern is then very frequently « dense fine speckled » (DFS). The ANAs responsible for this aspect are directed against the DFS70/LEDGF protein and are present in 2-22% of healthy subjects while they are very rarely found in patients suffering from systemic autoimmune rheumatic diseases (SARD). When isolated, with no other detectable specific anti-nuclear antibodies, anti-DFS70 is even considered a negative predictor for the development of a SARD. It is therefore interesting to identify and then confirm the presence of these autoantibodies when investigating the significance of ANAs.