MULTIPLE SCLEROSIS AND AUTOANTIBODY POSITIVITY: DIAGNOSTIC VALUE AND CLINICAL IMPLICATIONS

Introduction: Multiple sclerosis (MS) is a chronic disease characterized by autoimmune, inflammatory, and neurodegenerative processes affecting the central nervous system. In recent years, increasing attention has been drawn to the coexistence of autoantibody positivity and other autoimmune diseases in MS patients. This study aimed to evaluate the frequency of autoantibody positivity in MS patients and its relationship with clinical, laboratory, and radiological features. Methods: Patients who were evaluated with a preliminary diagnosis of MS and continued regular follow-up in our clinic between November 2023 and February 2025 were included. Patients were divided into two groups according to the presence of autoantibody positivity. Demographic, clinical (Expanded Disability Status Scale [EDSS], history of concomitant autoimmune disease), laboratory, and magnetic resonance imaging (MRI) findings were compared. Results: A total of 68 patients were included, of whom 46 (67.6%) were female, with a mean age of 36.26±11.51 years. Relapsing-remitting MS was identified in 76.5% (n=52) of patients. The most common clinical manifestation was sensory symptoms, observed in 48.5%. Autoantibody positivity was detected in 27.9% of patients, with antinuclear antibody (ANA) being the most frequently positive (11.8%). Autoantibody positivity was significantly higher in females (p=0.017), and concomitant autoimmune disease was more frequent in this group (p=0.047). No significant differences were observed between groups regarding MS subtype, initial symptoms, EDSS score, MRI lesion distribution, or cerebrospinal fluid findings (p>0.05). Conclusion: A considerable proportion of MS patients exhibited autoantibody positivity, which was particularly associated with female sex and the presence of concomitant autoimmune diseases. Although autoantibody positivity was not predictive of clinical phenotype or disease severity, it may reflect systemic autoimmune susceptibility. These findings highlight the need for larger, prospective studies to elucidate the role of autoantibodies in MS pathogenesis