Devic's Disease & NMO (neuromyelitis optica)

Devic's Disease and NMO (neuromyelitis optica) are different names for the same condition, which affects the nervous system. It is one of a group of conditions called demyelinating diseases, which include multiple sclerosis, ADEM (acute demyelinating encephalomyelitis) and transverse myelitis.

Devic's / NMO is very rare. The exact figures aren't known but it's certainly much rarer than epilepsy (6 in 1000 people in Europe / North America) and multiple sclerosis (1 in 800 people in Europe / North America)

Symptoms

The symptoms are in two categories - Optic Neuritis (ON) and Transverse Myelitis (TM)

Optic Neuritis is inflammation of the optic nerve, which carries messages from the eye to the brain. There may be eye pain and a decrease in vision.

Transverse Myelitis is inflammation of the spinal cord. It can cause weakness, numbness or other sensory problems, as well as possible disturbances of bladder and bowel function. What limbs are involved depends on where the inflammation in the spinal cord is - for instance if the inflammation is in the neck all four limbs may be affected.

What are the main differences between Devic's / NMO and multiple sclerosis?

The main differences between Devic's / NMO and Multiple Sclerosis are: Devic's / NMO affects mainly the optic nerves and spinal cord. However, a percentage of patients will have brain involvement during the course of their disease, though not in a pattern consistent with MS.  Brain lesions do not exclude a diagnosis of NMO. Whereas MS can affect any part of the central nervous system.

Relapsing remitting MS (RRMS) tends to change to a gradually progressive stage but Devic's / NMO does not.

Attacks of Devic's / NMO tend to be more severe with lasting disability, while initial attacks of RRMS recover almost fully.

Diagnosis

The symptoms of Devic's / NMO are similar to those of a number of other conditions such as multiple sclerosis and ADEM, so tests are carried out to exclude those. An MRI scan of the brain and spinal cord will almost certainly be carried out, and possibly a lumbar puncture, and a visual evoked response test. This is a non-invasive test which checks the speed of nerve impulses in the optic nerve.

Treatment

There are four aspects to treatment:

• Treating the acute attack, often with steroid medications.
• Preventing relapses using drugs to suppress the immune system.
• Treating residual symptoms from any relapse using whatever medications and therapies are appropriate.
• Rehabilitation to help the person recover from an attack, using a mixed team of doctors, nurses, physiotherapists, occupational therapists etc as appropriate.

Further Information

NHS NMO Specialised Services

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