Anti-DFS70 autoantibodies in undifferentiated connective tissue diseases subjects: what’s on the horizon?

Objective: The main objective was to determine the prevalence of anti-dense fine speckled (DFS70) antibodies in a stable population of undifferentiated connective tissue disease (UCTD) to better define their potential role. Methods: Immunological and clinical records of 91 long-standing UCTD patients were studied. DFS pattern was determined using the IIF ANA test on HEp-2 cells and anti-DFS70 antibodies were tested by chemiluminescence assay and by DFS70 line immunoassay. Results: Twelve (13.2%) of 91 serum samples were positive for anti-DFS70 antibodies by chemiluminescence assay and line immunoassay. There was no statistical significance between the prevalence of anti-ENA and anti-DNA autoantibodies in patients with and without anti-DFS70 antibodies. No differences were found in the clinical characteristics of both groups. The presence of the anti-DFS70 antibodies was related to the younger age class. Conclusion: The high prevalence of anti-DFS70 antibodies in the UCTD patients suggested the potential role of these autoantibodies as a marker in the evolution of UCTD to CTD.