Neuromyelitis Optica Spectrum Disorder (NMOSD)

What is neuromyelitis optica spectrum disorder?

Neuromyelitis optica spectrum disorder (NMOSD) is a rare, chronic disorder of the spinal cord and brain that is characterized by inflammation of the optic nerve and spinal cord. Affected individuals experience attacks followed by periods of remission, which can last anywhere from a few days to years. 

What are the symptoms of neuromyelitis optica spectrum disorder?

The major symptoms of this condition are inflammation of the optic nerve (optic neuritis) and inflammation of the spinal cord (myelitis). The former causes eye pain that is quickly followed by vision loss; it can be present in just one or both eyes. The latter impacts some, if not all, motor, autonomic, and sensory functions under a certain level on the body. This results in symptoms like pain in the limbs and/or spine, paralysis of the lower limbs, and diminished bowel and bladder control. Sensory loss, changes in deep tendon reflexes, stiffness, headaches, and pain in the limbs or back are other possible effects. 

What causes neuromyelitis optica spectrum disorder?

While the exact cause of this condition is unknown, it is categorized as an autoimmune condition. This means that the immune system mistakenly attacks the body. 

How is neuromyelitis optica spectrum disorder diagnosed?

Doctors will look at a patient’s history, look for the characteristic symptoms of the disorder, perform a clinical evaluation, and run a number of tests. These tests include spinal taps, blood tests, CT and CAT scans, MRIs, X-rays,and cerebrospinal fluid exams.

An important part of diagnosis is distinguishing NMOSD from multiple sclerosis, as they present very similarly. Patients are often misdiagnosed. 

What are the treatments for neuromyelitis optica spectrum disorder?

There are FDA approved treatments for NMOSD: Soliris, Enspryng, and Uplinza. 

For someone experiencing an attack, doctors will administer high doses of corticosteroids via IV, and some may benefit from plasma exchange as well. Patients are then prescribed immunosuppressive drugs to manage their condition. There are many possible drugs that fall into this category, such as rituximab, corticosteroids, mycophenolate mofetil, and azathioprine. Additionally, doctors may prescribe carbamazepine for spasms during attacks and antispasticity agents for those with spasticity issues that result in motor deficits. 

Where can I find out more about neuromyelitis optica spectrum disorder?

• • NORD
  • OHSU Brain Institute
  • Mayo Clinic
  • The Sumaira Foundation for NMO