Neuromyelitis optica (NMO) is an autoimmune disease of the central nervous system (CNS) that mainly affects the optic nerves and spinal cord. It is sometimes referred to as NMO spectrum disorder or NMOSD.

In NMO, the body's immune system mistakenly attacks healthy cells and proteins in the body, most often those in the spinal cord and eyes. Symptoms include:

• Optic neuritis, which causes pain in the eye and vision loss
• Transverse myelitis, which causes weakness or paralysis of arms and legs
• Numbness
• Loss of bladder and bowel control
• Severe nausea and vomiting, with hiccups from involvement of a part of the brain that controls vomiting

The disease is caused by abnormal autoantibodies that bind (attach) to a protein called aquaporin-4, activating other parts of the immune system and causing inflammation and damage to cells. This also results in the loss of myelin (the fatty substance that acts as insulation around nerve fibers and helps nerve signals move from cell to cell) in the brain and spinal cord.

NMO is different from multiple sclerosis (MS). Attacks are usually more severe in NMO than in MS, and NMO is treated differently than MS. Most individuals with NMO experience clusters of attacks days to months or years apart, followed by partial recovery during periods of remission. Women are more often affected by NMO than men. African Americans are at greater risk of the disease. The onset of NMO varies from childhood to adulthood, with two peaks, one in childhood and the other in adults in their 40s.

There is no cure for NMO. The U.S. Food and Drug Administration (FDA) has approved three drug treatments (eculizumab, inebilizumab-cdon, and satralizumab-mwge) which can reduce the risk of relapses in adults who are anti-aquaporin-4 antibody positive.

NMO relapses and attacks are often treated with corticosteroid drugs and plasma exchange (also called plasmapheresis, a process used to remove harmful antibodies from the bloodstream). Immunosuppressvie drugs used to prevent attacks include mycophenolate mofetil, rituximab, and azathioprine. Pain, stiffness, muscle spasms, and bladder and bowel control problems can be managed with medications and therapies.

Individuals with major disability may require physical and occupational therapy, along with social services professionals to address complex rehabilitation needs. Most individuals with NMO have an unpredictable, relapsing course of disease with attacks occurring months or years apart. Disability is cumulative, the result of each attack damaging new areas of the central nervous system.

• Inflammation of the optic nerve (optic neuritis)
• Temporary vision loss
• Inflammation of the spinal cord (acute transverse myelitis)
• Pain
• Abnormal sensations
• Weakness in the arms and legs
• Bladder and bowel control problems
• Episodes of nausea and vomiting

• Neurologist
• Ophthalmologist
• Physical therapist
• Occupational therapist