Neuromyelitis optica (NMO) also known as Devic disease is a rare yet severe disease.
Neuromyelitis optica (NMO) also known as Devic disease is a rare yet severe disease. In this condition, antibodies (proteins) are produced against the cells in the central nervous system. It specifically affects the myelin, which is the insulation sheath around the nerves. It is a chronic disorder of the brain and spinal cord and causes inflammation of the optic nerve (optic neuritis) and spinal cord (myelitis). The condition most often strikes during childhood. It can also affect adults who are in their 40s. It is especially common in young women compared to men. NMO can cause painful eyes, facial pain, headache, and other systemic symptoms.
The characteristic symptoms of NMO are similar to optic neuritis (inflammation of the optic nerve, which is responsible for vision) or transverse myelitis (inflammation of the spinal cord).
The possible signs and symptoms of NMO include:
- Pain in the eyes
- Loss of vision
- Facial pain
- Weakness or numbness in the arms and legs
- Paralysis of the arms and legs
- Difficulty controlling the bladder or bowels
- Uncontrollable vomiting and hiccups
- Confusion, seizure, or coma
What are the types of NMO?
There are two types of NMO:
- Relapsing form: In this, there are periodic flare-ups with some phases of recovery in between. This is the most common kind that affects women more than men.
- Monophasic form: This involves a single attack that lasts only a few months. The symptoms go away but may come back and get worse over time. Both men and women are equally affected.
What happens in NMO?
NMO is mainly characterized by inflammatory areas in the optic nerve and spinal cord. The inflammatory lesions are caused when the immune system mistakes the body’s cells as foreign bodies and recruit white blood cells and antibodies to eliminate them. In 80% of the NMO cases, auto-antibody is developed against aquaporin 4, a water channel protein expressed on the type of supporting brain cells. Demyelination occurs during the inflammatory process. It is the destruction of insulation cover over the brain cells.
How is NMO treated?
This condition is often not curable. However, the health care provider can prescribe medicines or other treatments to reduce the effects of the disease and relieve symptoms. These may include:
- Corticosteroid drugs to halt the immune system's effect on nerves
- Immunosuppressant drugs
- A process called plasmapheresis, which removes proteins from the blood that may be playing a role in the condition
- Other treatments to address symptoms, such as pain and loss of bowel and bladder control
What are the complications of NMO?
There are several possible complications of NMO, including: