NEUROMYELITIS OPTICA (NMO)
Neuromyelitis Optica is an immunological disorder characterized by inflammation and demyelination of the eye nerve (optic neuritis) and the spinal cord.
- Neuromyelitis Optica which is also known as Devic’s disease is a very rare condition and is often misdiagnosed as multiple sclerosis or thought to be a type of multiple sclerosis.
- Recent research has suggested that neuromyelitis optica is probably a different disease.
- The condition can be monophasic or relapsing. Monophasic meaning that these attacks can happen over a period of days or weeks, or relapsing meaning that these attacks may go for a long time, even months and years but can come back. Relapsing neuromyelitis optica can get worse over time.
- In the monophasic type, there are no subsequent attacks and it is easier for an individual to recover.
- The monophasic type affects both men and women equally, but women get the relapsing type more often than men.
- Young children can also get the condition.
CAUSES
The exact cause of the condition is not yet confirmed. It is an autoimmune disorder, meaning that the body immune system reacts against its own cell in the central nervous system, usually in the optic nerve and spinal cord, but sometimes in the brain.
Many people suffering from the condition has an antibody called Neuromyelitis Optica Immunoglobin G (NMO IgG) in their blood. Studies suggest that NMO IgG may damage aquaporin-4 (AQP4), the water channel surrounding the optic nerve and the spinal cord cells, causing the inflammatory effect of the condition.
The condition may sometimes appear after an infection or may be associated with another autoimmune condition.
It does not run in families.
SYMPTOMS
- Weakness or paralysis in arms or legs
- Blindness in one or both eyes
- Numbness or loss of sensation
- Painful spasms
- Uncontrollable vomiting and hiccups
- Bowel or bladder dysfunction from spinal cord damage
Children may experience confusion, seizures or coma.
DIAGNOSIS AND TREATMENT
To get the most appropriate treatment, the doctor must perform a thorough evaluation to rule out multiple sclerosis and other nervous system conditions that share the same symptoms with the condition.
To make a diagnosis, the doctor will review your medical history and symptoms and perform a physical examination. The doctor may also perform:
- Blood tests to detect NMO IgG. This test helps the doctor to make an early diagnosis.
- Lumbar puncture where a needle is inserted into your lower back to remove a small amount of spinal fluid to test for the levels of immune cells, antibodies and proteins in it.
- Stimuli response test to learn how well your brain responds to stimuli such as sound, touch or sights.
- A neurological exam where your muscle strength, movement, cognitive functions, speech, coordination, and sensation are examined.
- Imaging tests such as MRI to create a detailed view of your optic nerves, spinal cord, and brain.
- An eye doctor may also be involved in your examination.
TREATMENT
No cure exists for the condition, but treatment options may help you feel better or treat an attack.
Treatment option may include
- Corticosteroid medications passed intravenously.
- Plasmapheresis or plasma exchange therapy. In this procedure, some blood is removed from your body, and blood cells are separated from plasma. The blood is later mixed with a replacement solution and returned to the blood. This procedure helps remove antibodies that cause inflammation from the blood.
- To prevent future attacks and relapses, doctors may recommend that you take a lower dose of corticosteroid for a long period of time. You may also be asked to take immunosuppressive medications.