Cogan's syndrome

Cogan syndrome is an autoimmune disease, which means that it occurs when the immune system begins to attack the tissues of the body. This is called an autoimmune response. Specifically, the immune systems of people with Cogan syndrome begin to attack the tissues of the eyes and the inner ears. In some cases, the autoimmune response may also be directed against blood vessels. The exact reason that people with Cogan syndrome have an autoimmune response against the tissues of the eyes and the inner ears is not well-understood. For some people, it may be that symptoms of Cogan syndrome begin after an infection.

Cogan syndrome is diagnosed when a doctor observes signs and symptoms consistent with the syndrome. If Cogan syndrome is suspected, other diseases that may have similar signs and symptoms must be excluded. These diseases include syphilis, Lyme disease, Epstein-Barr virus, and Meniere disease. Laboratory tests to exclude other diseases may include blood tests, urinalysis, and studies to analyze liver function. In some cases, blood tests for a specific antibody related to Cogan syndrome may be completed.

If a diagnosis of Cogan syndrome is suspected, it is suggested that the affected individual see an ophthalmologist and otolaryngologist to determine if there are other symptoms consistent with Cogan syndrome.

Changes (mutations) in a specific gene are not known to cause Cogan syndrome. This means that Cogan syndrome is not thought to be passed directly from parent to child, and the syndrome is not thought to run in families. In general, family members of an individual with an autoimmune disease are thought to be at an increased risk to develop an autoimmune disease themselves. Although there are not reports of Cogan syndrome running in families, it is possible that family members of people with Cogan syndrome are at an increased risk to develop other autoimmune diseases.

Most people with Cogan syndrome respond well to corticosteroids or immunosuppressive agents. However, in some cases the medications may not be effective, or the syndrome may have progressed too quickly for the medications to relieve symptoms. In these cases, the symptoms of Cogan syndrome may lead to permanent vision or hearing loss. Permanent hearing loss is more common than permanent vision loss, and hearing loss may not be improved with the use of medications. The medications used to treat Cogan syndrome may have side-effects, so the risks and benefits of each medication must be considered.

The long-term outlook for people with Cogan syndrome also depends on the involvement of the blood vessels. If the blood vessels are affected by the autoimmune response associated with Cogan syndrome and the treatment is not effective, symptoms such as stomach pain or headaches may persist. Life- threatening complications of Cogan syndrome are rare, but may include an aneurysm of the aorta.