Behçet's disease. New perspectives on an enigmatic syndrome.

Behçet's disease is a multifaceted syndrome characterized by oral and genital ulcerations and ocular abnormalities including keratitis, optic neuritis, and uveitis. The disease has multiple systemic associations that include involvement of the gastrointestinal, cardiovascular, and central nervous systems as well as the joints, blood vessels, and lungs. Infrequently observed in the Americas and Western Europe, it has been more commonly seen in Turkey and Japan. Human lymphocyte antigen (HLA)-Bw51, HLA-B27, and HLA-B12 have each been associated with various manifestations of Behçet's disease. Numerous etiologies have been proposed, including environmental, virologic, bacterial, and immunologic factors; an autoimmune basis, characterized by circulating immune complexes and complement activation, has gained increasing acceptance. Although tetracycline remains the drug of choice for the oral ulcers of Behçet's disease, topical corticosteroids and topical anesthetics have been used for both oral and genital involvement. Oral corticosteroids continue to be the mainstay of systemic therapy, although various immunomodulators and anti-inflammatory agents, such as azathioprine, cyclophosphamide, chlorambucil, colchicine, dapsone, and cyclosporine, have been employed successfully.