Cogan's syndrome: organ-specific autoimmune disease or systemic vasculitis? A report of two cases and review of the literature.

Cogan's syndrome is a rare disorder of unknown origin characterized by inflammatory eye disease and vestibuloauditory symptoms. Typically, young adults suffer from interstitial keratitis and sudden onset of tinnitus and hearing loss. Few cases (around 150) have been published and thus it is difficult to determine the percentage of patients with underlying systemic disorders such as systemic vasculitis. The variety of systemic manifestations is large and includes fever, splenomegaly, lymphadenopath, and musculoskeletal complaints. Systemic vasculitis can be seen in around 10% of cases and may involve the large vessels, appearing as Takayasu-like vasculitis with affection of the aortic valve but also the coronary arteries and the small kidney vasculature. Evaluating the exact extension of the systemic features determines the choice of treatment. While corticosteroids have proved to be of short-term benefit, long-term treatment with immunosuppressive drugs is controversial. Auditory function in deaf patients has often been restored successfully with cochlear implants. To illustrate the nature of the syndrome, we present two patients with a wide clinical spectrum of symptoms from local disease restricted to the eyes and ears to a widespread vasculitis affecting arteries of the brain, kidney and the upper and lower extremities. We then review the typical aspects as well as the etiology of the disease.