Evaluation of the Pattern of Antinuclear Antibodies (ANA) Profile among Patients Suffering from Three Major Rheumatic Diseases.

Background and Objective: Autoimmune diseases (AIDs) are characterized by tissue destruction or organ dysfunction by the body's own immune system. The antinuclear antibodies (ANA) test is a helpful test for diagnosing and classifying ANAassociated rheumatic diseases (AARDs). This study aimed to evaluate the frequency and profile of autoantibodies among patients suffering from systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and Sjogren's syndrome (SS). Materials: This cross-sectional study was performed on patients who referred to the Rheumatology Clinic of Birjand University of Medical Sciences. Demographic data and information about risk factors were collected by a questionnaire. In confirmed cases, the presence of autoantibodies was detected by Fluorescent method (FANA). In all positive patients, ANA profiles were identified. Findings: Totally, 138 patients were included in this study. Prevalence of the three main diseases including SLE, RA, and SS was 45.5%, 39.0%, and 15.4%, respectively and being overweight was the most common risk factor. The rate of positive FANA test was 71.4%, 43.8%, and 78.9% in SLE, RA, and SS, respectively. In the case of autoantibodies, Ro-52 autoantibody had the highest prevalence. The most common co-incidence of autoantibodies was for DFS70 with PM-Scl100. Conclusion: The results of this study showed that the mean titers of ANAs were higher in SS patients. The Ro-52 autoantibody was the most commonly detected autoantibody. There was no specific profile of autoantibodies for none of the studied diseases. Further studies are needed to evaluate the correlation between the presence of particular autoantibodies with the prognosis of the patients. [ABSTRACT FROM AUTHOR]