Overlap syndrome involving anti-OJ antibody-positive polymyositis, systemic lupus erythematosus and Sjögren's syndrome: A case report and literature review.

Anti-OJ antibody is relatively rarely detected in patients with the anti-synthetase syndrome, which is polymyositis (PM)/dermatomyositis (DM) with anti-aminoacyl transfer ribonucleic acid (RNA) synthetase antibodies. There have been few case reports of anti-OJ antibody-positive PM/DM complicated by other connective tissue disorders. Herein, we report the case of a 33-year-old woman who was admitted to our hospital with fever, muscle weakness, and dyspnoea on exertion. She was diagnosed with anti-OJ antibody-positive PM, overlapping systemic lupus erythematosus, and Sjögren's syndrome (SS). Her symptoms and clinical findings improved after treatment with prednisolone 1 mg/kg/day without immunosuppressive agents. This is the first case of overlap syndrome with anti-OJ antibody-positive PM, systemic lupus erythematosus, and Sjögren's syndrome.