Diseases of obscure etiology: sarcoidosis, Wegener's granulomatosis, and midline granuloma.

Three distinct diseases of undetermined etiology have been presented: sarcoidosis, Wegener's granulomatosis, and midline (nonhealing) granuloma, all of which have similar clinical presentations in the midface. The correct diagnosis is essential because the treatment of each disease is different. Sarcoidosis responds best to corticosteroids, Wegener's granulomatosis to cyclophosphamide, and midline granuloma to radiation therapy. The otolaryngologist should be familiar with these diseases, since their important clinical manifestations are most frequently found in the nose, sinuses, and related structures. Early recognition by the otolaryngologist may determine the fate of patients with these disorders.