A Case Report of Rheumatoid Arthritis With a Migratory Pattern.

Rheumatoid arthritis (RA) is a systemic autoimmune disease that classically presents with symmetric polyarthritis. However, atypical manifestations such as migratory joint pain can obscure diagnosis, particularly in patients with pre-existing degenerative joint conditions. We report the case of a 74-year-old woman with a history of osteoarthritis (OA), obesity, and multiple comorbidities who developed acute, migratory joint and muscle pain over several weeks. Her symptoms exhibited a shifting pattern, initially involving the left wrist and groin, before progressing to the right upper extremity with notable swelling and functional impairment. Laboratory evaluation revealed a positive anti-cyclic citrullinated peptide (anti-CCP) antibody and elevated inflammatory markers, including C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). Rheumatoid factor (RF), antinuclear antibodies (ANA), and antineutrophil cytoplasmic antibodies (cytoplasmic (c-ANCA), perinuclear (p-ANCA), and atypical p-ANCA) were negative. Imaging studies excluded acute structural or vascular pathology. Despite her overlapping OA symptoms and seronegativity for RF, the patient's clinical trajectory and positive anti-CCP supported a diagnosis of RA with an atypical, migratory presentation. She experienced partial symptomatic improvement with corticosteroids and was referred to rheumatology for initiation of disease-modifying antirheumatic drugs (DMARDs). This case underscores the need to consider RA in the differential diagnosis of migratory arthralgia, especially in older adults with existing joint disease, and highlights the diagnostic utility of anti-CCP antibodies in seronegative presentations.