How Does Neuromyelitis Optica Affect The Body & What Triggers It?

Neuromyelitis optica causes various serious symptoms in the patient. The condition affects the vision as well as the movements. Patient experiences poor vision, low vision at night and vision loss. Eye pain is also experienced in neuromyelitis optica. The attack of neuromyelitis optica occurs due to various triggers.

Neuromyelitis optica is the conditions characterized by damage to the optic nerve and spinal cord. In some cases, the condition also affects the brain. It is a debilitating autoimmune disease. The immune system of the body starts attacking the optic nerve and spinal cord leading to demyelination of these nerves. The severity of symptoms depends upon the extent of damage to these nerves. Following are some of the symptoms experienced by the patient suffering from neuromyelitis optica:

Visual Symptoms: As the disease affects the optic nerves, the symptoms are related to vision. The symptoms due to damage of optic nerve include pain in the eyes, poor vision, difficulty seeing at night, loss of vision, and movement of eyes becomes difficult. The severity of visual problems is more in neuromyelitis optica as compared to normal cases of optic neuritis. Differentiation of neuromyelitis optica from optic neuritis is done based on the fact that in neuromyelitis optica, there is a rapid succession of optic neuritis.¹

Traverse Myelitis: Traverse myelitis is the condition occurs when the immune system of the body attacks the spinal cord. The symptoms related to transverse myelitis, experienced by the patient suffering from neuromyelitis optica, are severe as compared to symptoms experienced in multiple sclerosis. The patient may experience poor bladder control, pain, numbness and weakness in the lower extremities.² In severe cases, the patient may suffer from paralysis. The patient may also present radicular pain or Lhermitte sign.

Neuromyelitis optica can be triggered in the following conditions:

Chemicals: It has been found that cocaine triggers the occurrence of neuromyelitis optica; more specifically traverse myelitis in at least one patient. The possible mechanism proposed for this phenomenon is immune sensitization and generation of antibodies due to Bloor Brain Barrier disruption and damage of astrocytes.⁴

Bacterial Infection: Bacterial infection may also trigger neuromyelitis optica attack. This is because of the reason that during infection the immune system of the body is hyperactivated. Infections include ear infections, skin infections, and pneumonia.⁵

Viral Infection: Various viral infections such as varicella-zoster infection, CMV infection and HIV infection may cause neuromyelitis attack.⁵

Vaccination: It has been found that there is a small risk of relapsing neuromyelitis optica associated with administration of vaccines.⁶

Cancer: Some cancers are also known to trigger the immune system that may lead to neuromyelitis attack.⁵

Causes Of Neuromyelitis Optica

Neuromyelitis optica occurs when there are demyelination and inflammation of the optic nerve and spinal cord.

Neuromyelitis optica is an autoimmune disorder. Antibodies against the nerve are formed in the body and these antibodies attack the optic nerve and spinal cord. In some cases, the brain also gets affected by these antibodies. In multiple sclerosis, the exact antibody has not been found but neuromyelitis optica is the condition caused by a specific type of antibody against Astrocytic Aquaporin 4 (AQP4). It is a water transport channel found in the optic nerve and spinal cord. Water imbalance occurs because of the attack on these water channels. Demyelination occurs because of the damage to oligodendrocytes.³

Another antibody that causes neuromyelitis optica is anti-MOG+. The condition is characterized by anti-MOG associated encephalomyelitis which is an inflammatory demyelinating disease.

In some cases of neuromyelitis optica, anti-neurofascin (anti-NF) auto-antibodies are also found. These antibodies affect the nodes of Ranvier in neurons.

Neuromyelitis optica results in pain, numbness, and paralysis, especially in lower extremities. The patient may also have vision problems. Factors that trigger the attack include certain chemicals such as cocaine, bacterial and viral infection, cancer and vaccination.

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Also Read:

• Difference Between Neuromyelitis Optica and Multiple Sclerosis
• How Dangerous Is Neuromyelitis Optica & Is It Contagious?
• How Do You Stop Neuromyelitis Optica From Spreading?
• Is Neuromyelitis Optica A Progressive Disease & Alternative Treatments For It
• How Common Is Neuromyelitis Optica or Is It A Rare Disease?
• Life Expectancy Of Someone With Neuromyelitis Optica
• What Are The Ways To Prevent Neuromyelitis Optica & Does It Reoccur?