Neuromyelitis optica (NMO) is a chronic health condition that affects nerves in the eyes, spinal cord, and sometimes brain. It’s also known as Devic disease or Devic syndrome. It may cause vision loss, muscle weakness, and other symptoms.
Read on to learn more about this condition, including how it’s diagnosed and treated.
NMO is believed to be an autoimmune condition, where the body’s own immune system attacks healthy cells.
In NMO, the immune system attacks the central nervous system (CNS) and optic nerves. Your CNS includes your spinal cord and brain. Your optic nerves carry signals between your eyes and brain.
When your immune system attacks your CNS and optic nerves, it can cause inflammation and nerve damage. This can produce symptoms such as eye pain, vision loss, and muscle weakness.
NMO is more common in people of Asian, African, and Native American descent. Women account for more than 80 percent of cases of NMO.
NMO symptoms most often appear in adults in their 40s but may develop at any age. They may include:
- eye pain in one or both eyes
- temporary vision loss in one or both eyes
- numbness, tingling, or other sensory changes
- muscle weakness or paralysis in your arms and legs
- loss of control of your bowel and bladder
- uncontrollable hiccuping
- nausea and vomiting
Most people with NMO develop a relapsing form of the disease. They experience multiple episodes of NMO symptoms known as relapses. These may occur months or years apart.
People with relapsing NMO tend to partially recover between relapses. Many of them eventually develop lasting vision loss and muscle weakness or paralysis that persist between relapses.
A smaller number of people with NMO develop a monophasic form of the disease. They experience a single episode of symptoms that may last for several months. They may also have lasting vision loss and muscle weakness.
Contact your doctor right away if you develop NMO symptoms such as eye pain, vision loss, muscle weakness, loss of sensation, or loss of control of your bowel or bladder.
To make an NMO diagnosis, your doctor will ask you about your symptoms and medical history and conduct a physical exam.
The following tests can help your doctor to make an NMO diagnosis:
- an eye exam, to assess your eye function and structure
- a neurological exam, to assess your strength, coordination, sensation, thinking, memory, vision, and speech
- magnetic resonance imaging (MRI), to create pictures of your spinal cord, brain, and optic nerves
- a spinal tap, to collect a sample of fluid from around your brain and spine for testing
- blood tests, to check for certain antibodies that are found in many people with NMO
About 70 percent of people with NMO produce a type of immune molecule known as anti-AQP4 antibodies. Your NMO treatment options will partly depend on whether or not you produce these antibodies.
Your doctor may prescribe several NMO treatments to help reverse recent symptoms or prevent future attacks.
Immediately following an NMO attack, your doctor may treat symptoms by injecting you with high doses of the corticosteroid methylprednisolone (Solu-Medrol).
If corticosteroids don’t improve your symptoms and you have anti-AQP4 antibodies, you may receive a plasma exchange (PLEX) to lower your antibody levels.
During this procedure, a healthcare provider removes blood from your body with an IV. Your plasma (the liquid part of your blood) is then separated from cells and replaced with a synthetic substitute. The healthcare provider then returns the blood to your body with an IV. The process may take hours and may be repeated several times over several days.
To prevent relapses, your doctor may also prescribe immune-suppressing medications.
If you produce anti-AQP4 antibodies, you may receive intravenous immune-suppressing medications including eculizumab (Soliris) or inebilizumab (Uplizna) to prevent future attacks.
Several other immune-suppressing drugs are used off-label to reduce the risk of recurrence. These include azathioprine (Imuran, Azasan), rituximab (Rituxan), or mycophenolate mofetil (Cellcept).
Your doctor may prescribe other medications, rehabilitative therapy, and lifestyle changes to help manage symptoms or complications of NMO.
Talk to your doctor to learn more about the potential benefits and risks of your treatment options.
NMO is similar to multiple sclerosis (MS) in several ways.
Both conditions are autoimmune disorders that affect nerve cells in the CNS and optic nerves. They may produce similar symptoms, such as vision loss and muscle weakness.
NMO differs from MS because:
- the specific immune cells and autoimmune processes that are involved in NMO aren’t the same as those involved in MS
- people with MS don’t have anti-AQP4 antibodies, while 70 percent of people with NMO do
- some of the treatments that work for MS don’t work for NMO
- NMO relapses also tend to produce more severe symptoms than MS relapses
- NMO tends to cause irreversible health problems more quickly than MS, although both conditions can cause lasting damage over time
NMO affects some people with the condition more severely than others.
The condition may eventually cause lasting health problems, such as vision loss, muscle weakness, and issues with bowel and bladder control.
It may affect your ability to see, get around, and complete day-to-day tasks. In severe cases, complications of the disease can make it difficult to breathe.
Your doctor and other members of your treatment team can help you develop a plan to manage your symptoms, improve your quality of life, and support your ability to complete daily tasks with NMO.
Your treatment and management plan may include:
- medications to help limit relapses, relieve symptoms, and treat complications
- physical therapy to help maintain or improve your strength and mobility
- occupational therapy to help you adapt to changes in how your body functions
- use of assistive devices to help you get around
- use of a ventilator to help you breathe
- changes to your diet or other habits
Your doctor may encourage you to meet with a social worker to help you access social support services such as disability benefits.
Your doctor may also refer you to a professional counselor or patient support group to help meet your mental health and social support needs.
Let your doctor or other members of your treatment team know if your symptoms change, you have concerns about your treatment plan, or you’re finding it difficult to manage the challenges of living with NMO.
It’s difficult to predict how NMO will develop in any one person. The condition causes more severe symptoms in some people and sometimes leads to potentially life threatening complications.
According to the authors of a review article in Clinical Medicine Journal, early treatment is important for reducing the risk of disability and death from NMO. Getting treatment may help limit relapses, prevent complications, and improve your long-term outlook.
The authors of the review report that roughly one-third of people with NMO who don’t get treatment die within 5 years of their first episode.
If you have NMO, eating a well-balanced diet is important for promoting good overall health. A registered dietitian can help you develop a healthy eating plan that’s sustainable for you.
A NMO disease diet includes:
- eating a variety of fruits, vegetables, whole grains, and lean protein
- limiting your intake of foods that are high in saturated fats or sugar, such as processed meats, pastries, and sweets
- drinking 6 to 8 cups of water or other sugar-free fluids per day
- avoiding or limiting your intake of alcohol and caffeine
Some NMO treatments may affect your appetite or weight. Talk to your doctor if you’re concerned.
Your doctor or dietitian may recommend changes to your dietary habits if you develop urinary frequency, constipation, or other challenges with your bladder or bowel habits.
If you receive a diagnosis of NMO, your long-term outlook will partly depend on the form of NMO that you develop, the treatment that you receive, and your overall health.
Following your recommended treatment plan may help limit relapses, prevent complications, and keep you healthier for longer.
Talk to your doctor to learn more about your treatment options and outlook with this condition.