Cogan syndrome

Cogan syndrome is a rare condition marked by repeated inflammation of the cornea—the clear front part of the eye—along with symptoms like fever, fatigue, weight loss, vertigo, tinnitus, and hearing loss. Without treatment, it can result in deafness or blindness. The classic form was first identified by D. G. Cogan in 1945. This rheumatic disease causes inflammation in the eyes and ears, leading to vision problems, hearing loss, and dizziness.

In about 15% of cases, inflammation of blood vessels (vasculitis) can spread to other organs, potentially causing major damage or, rarely, death. It most often appears in a person’s 20s or 30s. The exact cause is unknown, but it is thought to be an autoimmune disorder where the immune system mistakenly attacks eye and ear tissue. Some patients have autoantibodies in their blood that target inner ear tissue in lab tests.

Infection with Chlamydia pneumoniae—a common cause of mild pneumonia—has been found in some patients before the syndrome develops, suggesting the infection might trigger the autoimmune response, though most people infected with this bacterium never develop Cogan syndrome. Diagnosis is tricky. Blood tests may show abnormal white blood cell counts, high erythrocyte sedimentation rate, elevated C-reactive protein, high platelet levels, or low red blood cell counts, but none reliably confirm the disease.

Diagnosis

A slit-lamp eye exam is essential. High-resolution MRI and tests for antibodies against inner ear antigens may also help. The syndrome can occur in children, where it is especially hard to recognize. For severe cases, oral corticosteroids are used to reduce inflammation.

Treatment

If high doses are needed or the disease doesn’t respond, other immunosuppressive drugs like methotrexate, cyclophosphamide, cyclosporine, or azathioprine may be prescribed, sometimes in combination. If blood vessel damage in the ear occurs, a cochlear implant can help restore some hearing. Cinnarizine is mainly used to treat nausea and vomiting associated with motion sickness, vertigo, Ménière's disease, or Cogan syndrome.