Tuberculosis Presenting as Migratory Arthritis: A Case Report from Iraq.

Extrapulmonary tuberculosis is uncommon, and musculoskeletal involvement presenting as migratory arthritis is particularly rare in immunocompetent individuals, often leading to misdiagnosis and delayed treatment. We report the case of a 66-year-old man with diabetes mellitus who presented with recurrent migratory inflammatory arthritis affecting multiple joints over 1 year, without initial pulmonary symptoms. He was initially diagnosed with rheumatoid arthritis based on positive rheumatoid factor and elevated inflammatory markers and was treated with disease-modifying antirheumatic drugs without clinical improvement. At presentation, he reported severe shoulder pain, morning stiffness, weight loss, and night sweats. Imaging revealed right upper lobe consolidation and a metabolically active cavitary lung lesion on PET-CT. Bronchoalveolar lavage culture confirmed Mycobacterium tuberculosis. Antituberculous therapy was initiated, resulting in marked clinical improvement and resolution of arthritis within weeks. This case highlights tuberculosis as an important, underrecognized cause of migratory arthritis and emphasizes the need to consider infectious etiologies in treatment-resistant inflammatory joint disease, particularly in endemic regions.