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

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.

Frequency of ANA/DFS70 in Relatives of Patients with Rheumatoid Arthritis Compared to Patients with Rheumatoid Arthritis and a Healthy Population, and its Association with Health Status.

Introduction: DFS70 ANAs have attracted interest due to their frequency in individuals with no clinical evidence of systemic autoimmune rheumatic disease, groups with genetic risk for rheumatoid arthritis (RA) were not assessed.

Objective: To determine the frequency of ANA and DFS70 ANA in blood relatives (BR) of people with RA compared to patients with early RA (ERA), and control individuals, and its association with health status.

Methodology: A cross-sectional study with an analytical component.

Frequency of Positive ANCA Test in a Population With Clinical Symptoms Suggestive of Autoimmune Disease and the Interference of ANA in its Interpretation.

Background: Antibodies against neutrophil cytoplasm (ANCA) are associated with vasculitis. There are different methods to determine their presence. The interference of antinuclear antibodies (ANA) in the differentiation between P-ANCA and C-ANCA patterns has been described.