A 40-year-old man presents with a 2-week history of recur- rent oral ulcers, genital ulcers, intermittent arthritic pain of the knees, and abdominal pain. Physical examination reveals shallow ulcerations of the mucosa of the glans penis, as well as oral aphthous ulcers and conjunctivitis. Which of the following is the most likely diagnosis?

Behget disease is a systemic vasculitis characterized by oral aphthous ulcers, genital ulceration, and ocular inflammation, with occasional involvement of the nervous, gastrointestinal, and cardiovascular systems. The mucocutaneous lesions show a non-specific vasculitis of arterioles, capillaries, and venules. The cause of the necrotizing inflammation of small blood vessels is not known, but an association with specific HLA subtypes suggests an immune basis. Herpes (choice B) does not present with arthritis.Diagnosis: Behqet disease