Autoimmune Epilepsy Highlights: Autoimmune Limbic Encephalitis

In January we started to highlight Auto-Immune Epilepsies - take a look back to review these earlier posts:

Autoimmune Epilepsy

Rasmussen Syndrome

FIRES (Febrile Illness-Related Refractory Seizures)

Next up:  Autoimmune limbic encephalitis

A major role of our immune system is to recognize and eliminate infections. But sometimes parts of the immune system may instead react with our own body to cause autoimmune diseases. 

When this reaction is against proteins of the limbic areas of the brain, this is called ‘autoimmune limbic encephalitis’.

There are 2 main types: 

• paraneoplastic limbic encephalitis (PLE)

• and non-paraneoplastic limbic encephalitis (NPLE)

Paraneoplastic limbic encephalitis (PLE) is when cancer and a tumor is involved.  Because of the tumor the immune system is activated and can, in turn, attack the brain. 

Non-paraneoplastic limbic encephalitis (NPLE) is when a tumor or cancer is not involved and it is actually the most common type. 

• These patients have specific antibodies in their blood that target the brain, particularly the hippocampus and other limbic areas. 

  
  

Some symptoms we might see in these patients:

In addition to the usual symptoms of encephalitis such as:

• altered consciousness, fever, and focal neurological deficits

• limbic encephalitis can present with psychiatric manifestations and seizures.

• Symptoms can vary widely and may include: memory loss, cognitive impairment, changes in behavior and personality, seizures, and even psychiatric symptoms like psychosis or depression. 

Many of these patients improve if they are treated with drugs that suppress the immune system and reduce the levels of the antibodies. 

Importantly, making an early diagnosis improves outcomes.  Often due to their seizure complications we will see these patient’s in our clinic and hospital labs. 

As Neurodiagnostic Technologists being aware of this condition and other auto-immune epilepsies will help us be a better resource for our patients.

Roya Tompkins, MS, REEG/EP T, RPSGT

Resources:  

Encephalitis International

National Institute of Health