Neurosarcoidosis

Alternative names:

sarcoidosis - nervous system

Definition:

A complication of sarcoidosis involving inflammation and abnormal deposits in the tissues of the nervous system.

Causes, incidence, and risk factors:

Sarcoidosis is a chronic disorder that affects many body systems. Over 90% of cases involve the lungs and may also involve any other area of the body. About 5% of cases will involve of some portion of the nervous system (neurosarcoidosis). The disorder involves an abnormal immune system response resulting in deposits of white blood cells and abnormal tissue cells in the affected organ.

Neurosarcoidosis may affect any part of the nervous system. Sudden, transient facial palsy is common with involvement of cranial nerve VII. Any nerve can be involved, including the nerves of the eye and the nerves that control taste, smell, or hearing. Muscle weakness and/or sensory losses can occur with peripheral nerve involvement. The brain or spinal cord may also be involved.

Neurosarcoidosis is a clinically significant complication of sarcoidosis because it increases the risk of permanent disability and, in some cases, death.

Sarcoidosis occurs in highly variable groups. In the U.S. it is more common in African-Americans, while in Europe it is more common in Caucasians. The disorder is slightly more common in people 25 to 50 years old, particularly women, but can occur at any age and to either sex. It is very rare in pediatrics. If it occurs in children, sarcoidosis usually involves the lungs.