What is Susac's syndrome?

Susac's syndrome is a rare, autoimmune disease. "Autoimmune" means that a person's immune system mistakenly attacks the person's own tissues. In Susac's syndrome, the immune system attacks the smallest blood vessels in the brain, retina (part of the eye), and inner ear. The blood vessels become blocked. Problems in the brain, retina, and inner ear occur due to decreased blood flow.

Who is affected by Susac's syndrome?

Susac's syndrome is rare, but when it occurs it strikes mainly females between the ages of 20 and 40. However, children as young as 8 and adults (both men and women) into their 50s can be affected.

What are the symptoms of Susac's syndrome?

Brain symptoms:

  • Severe headache, often with vomiting
  • Problems with thinking, such as short-term memory loss, confusion, slow thought processing, and reduced ability to solve problems
  • Inability to remain alert or focused
  • Slurred speech
  • Changes in personality
  • Mental problems such as depression, psychosis, aggression, anxiety, or withdrawal

Eye symptoms:

  • Dark area in one part of the visual field
  • Visual disturbance (described as a "like a dark shade or curtain is drawn over part of my vision.")
  • Loss of peripheral (side) vision

Inner ear symptoms:

  • Hearing loss
  • Dizziness (vertigo)
  • Ringing in the ears (tinnitus)

All three parts of the disease may not appear at the same time. Any one of the above symptoms may be the first sign of Susac's syndrome. It may take weeks, months, or even years for all three parts to show up, and some patients never have more than two of them.

What causes Susac's syndrome?

Susac's syndrome is caused by a person's own immune system attacking the endothelial cells— the cells that line the inner walls of our blood vessels—in the brain, retina, and inner ear. When attacked, the endothelial cells swell up and partly or completely shut off blood flow through the vessel. The resulting lack of oxygen and nutrients causes the affected organs to suffer.

What causes the immune system to malfunction in this way is not known.

Last reviewed by a Cleveland Clinic medical professional on 05/26/2017.


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