Analysis of Ana/Dfs70 Pattern in a Large Cohort of Autoimmune/Autoinflammatory Diseases Compared with First Degree Relatives and Healthy Controls Evaluated from Colombia

Abstract

Background: The presence of Antinuclear antibodies/Dense Fine Speckled 70 (ANA/DFS70) has been proposed as a negative biomarker in the process of exclusion of systemic autoimmune/autoinflammatory rheumatic diseases (SARD). The purpose was to evaluate and characterize ANA/DFS70 patients in a large Colombian population with SARD; rheumatoid arthritis (RA), Psoriasis (PsO), Undifferentiated connective tissue disease (UCTD), first-degree relatives of (FDR), and healthy controls (HC). Methods: ANA determination was performed using indirect immunofluorescence. Samples with positive dense fine granular staining in the nucleoplasm of the interphase cell (AC2) fluorescence were confirmed with CytoBead/ANA and ANA/modified (Knocked out for the PSPI1 gen). Results: 530 mestizo Colombian participants were included. ANA/DFS70 antibody positivity in the whole group was 2.3%, and 0.8% in SARD; no RA patients were positive. ANA/DFS70 positives in UCTD were three women; the average time of evolution of the disease was 9.4 years. The most frequent clinical findings were arthralgias, non-erosive arthritis, and Raynaud’s phenomenon. The PsO positive was a woman with C-reactive protein (CRP) positivity and a negative erythrocyte sedimentation rate (ESR) without any other positive autoantibody or extracutaneous manifestation. FDR and HC positives were 7/8 women. All were negative for other autoantibodies. Conclusions: ANA/DFS70 autoantibodies were present in Colombian patients with SARD at a shallow frequency, they were more prevalent in healthy individuals.

The significance of dense fine speckled pattern in antinuclear antibody‐associated rheumatic disease and coexisting autoantibodies: A propensity score‐matched cohort study

“…The concept of monospecific or isolated anti‐DFS70 antibody highlights the importance of examining other common autoantibodies in the diagnosis of AARD in patients with anti‐DFS70 antibodies. However, there is a lack of agreement on the definition of common autoantibodies, 1,27,43,44 leading to inconsistent diagnostic methods and results in the literature 45–48 . Defining common autoantibodies as those highly specific to AARD could aid in clarifying this concept in clinical practice and further research.…”

“…However, there is a lack of agreement on the definition of common autoantibodies, 1,27,43,44 leading to inconsistent diagnostic methods and results in the literature. [45][46][47][48] Defining common autoantibodies as those highly specific to AARD could aid in clarifying this concept in clinical practice and further research.…”