Muscle involvement in Behçet's syndrome: a case report.

Behçet's syndrome, a systemic vasculitis of unknown aetiology, is classically characterized by recurrent aphthous ulcers, genital ulcers, uveitis, and cutaneous lesions. Myositis in Behçet's syndrome is rare. A unique case of Behçet's syndrome with gastrocnemius and tongue myositis as the presenting manifestations is presented here. The patient was admitted with fever, recurrent aphthous ulcers, and swelling and pain of the tongue and legs. Phlebitis of the deep-tissue vessels was seen in the tongue biopsy. A gastrocnemius muscle biopsy showed obvious muscle fibre degeneration, accompanied by swelling of the vascular endothelial cells with abundant lymphocytic infiltration. After treatment with prednisone and thalidomide, the swelling of the tongue and legs was reduced. Therefore, in the case of recurrent oral ulcers accompanied by fever and muscle lesions, even in the absence of clinical findings such as genital ulcers or ophthalmitis, it is necessary to be alert to the possibility of Behçet's syndrome.