Autoimmune epilepsy

Learn when epilepsy is an autoimmune disease and why early diagnosis and the right treatment are important.

Update Date: 21.12.2024

Overview
Symptoms
Causes
Risk factors
Complications
Prevention
Diagnosis
Treatment
Preparing for an appointment
Overview
Symptoms
Causes
Risk factors
Complications
Prevention
Diagnosis
Treatment
Preparing for an appointment

Overview

Autoimmune epilepsy is a type of epilepsy where seizures are caused by the immune system mistakenly attacking brain cells. It can occur with conditions that affect the immune system, especially autoimmune encephalitis.

Autoimmune epilepsy also is known as autoimmune associated epilepsy and acute symptomatic seizures secondary to autoimmune encephalitis.

The immune system protects the body from viruses, bacteria and other substances that can cause illnesses. Antibodies are proteins that are part of the immune system. In autoimmune epilepsy, antibodies mistakenly target receptors in the brain. This leads to swelling in the brain, also known as inflammation, and seizures.

Antiseizure medicines usually don't do enough to manage seizures in people with autoimmune epilepsy. Instead, immunotherapy medicines help reduce the immune response on the brain.

When immunotherapy is started early, it can reduce inflammation and improve seizures. For some people, treatment can stop seizures completely. For others, seizures may continue after treatment.

Symptoms

Symptoms of autoimmune epilepsy may begin after an illness with a fever. Seizures come on suddenly and are serious. The types of seizures that may occur include:

  • Focal seizures. These are the most common type of seizure in autoimmune epilepsy. Sometimes focal seizures cause a change or loss of awareness. The seizures may cause the person to stare and not respond to the environment. Other types of focal seizures don't cause a change in awareness. These seizures cause different symptoms depending on which part of the brain causes them. Focal seizures may cause one part of the body to shake. Or they may cause a feeling that his has happened before, known as déjà vu. Focal seizures also may cause nausea or vision symptoms, such as flashing lights.
  • Faciobrachial dystonic seizures. These seizures cause muscle contractions on one side of the face and in an arm, both on the same side of the body.

Symptoms related to seizures include:

  • Seizures that happen several times a day.
  • Seizures that don't go away with antiseizure medicines.
  • Seizures that last more than five minutes or that occur close together without the person regaining consciousness, known as status epilepticus.

Autoimmune epilepsy symptoms also may include:

  • Memory loss and trouble with thinking.
  • Personality and behavior changes.
  • Involuntary movements or clumsy movements.
  • Irregular eye movements.
  • Changes in heart rate, blood pressure and other automatic functions.

When to see a doctor

Get emergency medical care if you or someone you are with has a seizure that lasts more than five minutes or if seizures occur one after another with a loss of consciousness. Also seek emergency medical care for high fevers or trouble breathing.

See your healthcare professional right away if you have had a seizure for the first time or if you have other symptoms of autoimmune epilepsy.

Causes

Autoimmune epilepsy is caused by the immune system attacking brain cells and leading to seizures. Antibodies are part of the immune system. They usually protect the body from viruses and infections. But in autoimmune conditions, the immune system attacks healthy cells. More recently, research has concluded that epilepsy can be an autoimmune disease.

Autoimmune epilepsy causes may include:

  • Autoimmune encephalitis. Autoimmune encephalitis (en-sef-uh-LIE-tis) is a group of conditions that causes swelling in the brain. This happens because the immune system mistakenly attacks brain cells. Autoimmune encephalitis causes a variety of symptoms, including seizures. It is the most common cause of autoimmune epilepsy. Certain types of autoimmune encephalitis are commonly linked to autoimmune epilepsy and are associated with antibodies that target NMDA-receptors, LGI1, CASPR2 and GAD65.
  • Rasmussen syndrome. In this condition, immune cells known as T cells cause inflammation and brain damage that lead to seizures. People with autoimmune epilepsy due to Rasmussen syndrome may continue to have seizures after treatment.
  • Cancer. Sometimes tumors trigger the immune system to attack healthy brain cells, known as paraneoplastic syndrome. This can lead to epilepsy.

Risk factors

The risk of autoimmune epilepsy is low, but it can occur in both adults and children. Risk factors include:

  • Having another autoimmune disease. These may include rheumatoid arthritis, Graves' disease, Hashimoto thyroiditis, Crohn's disease, ulcerative colitis or lupus.
  • Having a history of cancer.
  • Having a parent, sibling or child with an autoimmune disease.

Complications

Autoimmune epilepsy complications can include serious seizures that last more than five minutes or occur one after another. The person isn't conscious in between the seizures. These serious seizures are known as status epilepticus. They need emergency medical attention.

Sometimes autoimmune epilepsy can lead to seizures that don't stop with treatment.

Prevention

You may not be able to prevent autoimmune epilepsy. But getting cancer screenings can help your healthcare professional find tumors and treat them early. This could prevent autoimmune encephalitis triggered by cancers, which can be a cause of epilepsy. Talk with your healthcare professional about your cancer risk and if you should get screened for certain cancers.

Diagnosis

An autoimmune epilepsy diagnosis begins with a physical exam and a review of your symptoms.

Testings for autoimmune epilepsy includes lab tests, brain imaging and testing the electrical activity in the brain.

Lab tests

Lab tests check for antibodies in the immune system that are attacking brain cells and causing seizures.

Healthcare professionals test for antibodies by testing your blood or the fluid that surrounds your brain and spinal cord, known as cerebrospinal fluid. Cerebrospinal fluid is removed during a procedure known as a lumbar puncture. A healthcare professional numbs the lower back and uses a hollow needle to remove fluid for testing.

For some people with autoimmune epilepsy, these tests don't find antibodies.

Brain imaging

An MRI of your brain can look for signs of autoimmune epilepsy. You also may have a brain imaging test known as a fluorodeoxyglucose (FDG) PET scan. This test checks how well nutrients are being metabolized in the brain. This can offer clues about whether you have certain types of autoimmune encephalitis that may be causing seizures. Brain imaging also can rule out other possible causes of your seizures.

EEG

An electroencephalogram is a test that measures electrical activity in the brain. This test also is called an EEG. It may show seizure activity and can help diagnose autoimmune epilepsy. An EEG also can help rule out other conditions. Your healthcare professional may record seizure activity using a video EEG.

Treatment

Autoimmune epilepsy treatment differs from the treatment used for other types of epilepsy. Healthcare professionals use immunotherapy to reduce the immune system activity and treat seizures.

If cancer is the cause of autoimmune epilepsy, treating the cancer is an important part of treatment.

Immunotherapy

Immunotherapy medicines for autoimmune epilepsy may include:

  • High-dose corticosteroids. Your healthcare professional may treat you with methylprednisolone (Solu-Medrol) through an IV in your arm for up to five days. After this period, you may take methylprednisolone by IV regularly for weeks, gradually lengthening the time in between doses.

    Or you may take the steroid medicine prednisone orally. You take a high dose for up to five days, then a lower dose for several weeks. Over time, the dose of the oral medicine is lowered slowly. This is known as tapering.

  • Immunoglobulin. This medicine is taken through an IV in the arm for up to five days. Then you take lower doses of the medicine regularly for several weeks.

Depending on your response to the initial treatments, your healthcare professional also may recommend longer acting medicines that work on the immune system. These may include rituximab (Rituxan, Truxima, others), cyclophosphamide, mycophenolate (Cellcept, Myhibbin), azathioprine (Azasan, Imuran), or tocilizumab (Actemra, Tofidence, Tyenne).

Plasma exchange

Your healthcare professional also may recommend plasma exchange. A healthcare professional removes the liquid part of your blood and separates it from your blood cells. Then the blood cells are put back into your body and your body makes more plasma. This therapy helps remove the antibodies that are causing the immune system to attack brain cells.

Antiseizure medicines

Although antiseizure medicines don't work as well in people with autoimmune epilepsy, they may still play a role in your treatment. However, the effectiveness of these medicines may be limited. If you take immunotherapy and become seizure free, your healthcare professional may suggest slowly reducing your dose of antiseizure medicines over several months to see if seizures return.

Many people whose seizures are due to autoimmune encephalitis become seizure free after taking immunotherapy. It may take several months after the treatment for the seizures to stop. But seizures continue for some people even after immunotherapy. People with GAD65 antibodies are less likely to become seizure free.

If you have symptoms other than seizures, such as trouble with memory or speech, you may need rehabilitation. Occupational and speech therapy can help.

Surgeries

Rasmussen syndrome, which mainly affects children, usually doesn't respond to medicines. Brain surgery often is needed to treat this type of autoimmune epilepsy.

Preparing for an appointment

If your symptoms are serious, you might need emergency medical care.

If your symptoms are less serious, you may start by seeing your healthcare professional. Or you may be referred right away to a doctor who specializes in nervous system conditions, known as a neurologist.

What you can do

When you make the appointment, ask if there's anything you need to do in advance, such as fasting before having a specific test. Make a list of:

  • Your symptoms, including any that seem unrelated to the reason for your appointment.
  • Key personal information, including major stresses, recent life changes and family medical history.
  • All medicines, vitamins or other supplements you take, including the doses.
  • Questions to ask your healthcare professional.

Take a family member or friend along, if possible, to help you remember the information you're given.

For autoimmune epilepsy, some basic questions to ask include:

  • What's likely causing my symptoms?
  • Other than the most likely cause, what are other possible causes for my symptoms?
  • What tests do I need?
  • Is my condition likely short term or lasting?
  • What's the best course of action?
  • What are the alternatives to the primary approach you're suggesting?
  • I have these other health conditions. How can I best manage them together?
  • Are there restrictions I need to follow?
  • Should I see a specialist?
  • Are there brochures or other printed material I can have? What websites do you recommend?

Don't hesitate to ask other questions.

What to expect from your doctor

Your healthcare professional is likely to ask you several questions, such as:

  • When did your symptoms begin?
  • Do your symptoms occur all the time or off and on?
  • How bad are your symptoms?
  • What, if anything, seems to improve your symptoms?
  • What, if anything, appears to worsen your symptoms?

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