Anti-NMDA Receptor Encephalitis

The neurological condition resulting in sudden and severe behavioral changes.

The AddToAny Share Buttons plugin is not activated

By Jenny Ewen, BA, NREMT
Editor-In-Chief

Overview

First identified in 2007 by Dr. Joseph Dalmau, anti-NMDA receptor encephalitis is an auto-immune disease where antibodies attack the NMDA receptors in the brain (specifically the GluN1 subunit), causing a litany of symptoms due to the disruption in signals from the brain and swelling in brain tissue.

NMDA stands for N-methyl-D-aspartate, and anti- indicates that it’s an autoimmune response in the body. Encephalitis means swelling in the brain, causing several neurological symptoms, including behavioral changes, seizures, and coma.

NMDA receptors are responsible for the processes of learning and memory, and are located in neurons in the brain. NMDA receptors are also involved in other neurological disorders, including Alzheimer’s and depression.

Anti-NMDA receptor encephalitis is still quite difficult to identify from other psychiatric disorders, but most commonly occurs in children and young adults and most often in women. It is not yet known what causes it, but environmental and genetic triggers are suspected to be involved.

Signs and Symptoms

Anti-NMDA receptor encephalitis can develop over weeks or months with symptoms increasing in severity during that time and requiring hospitalization. 

 

While often diseases present with many symptoms and a patient could experience only some of them, people who develop anti-NMDA receptor encephalitis typically present with nearly all of the symptoms by the time it’s diagnosed. In 90% of diagnosed cases, patients experience severe psychiatric/behavioral symptoms.

 

Symptoms include:

 

  • Changes in behavior, including paranoia, hallucinations, and agitation
  • Worsening memory
  • Difficulty speaking
  • Problems with cognition (thinking, learning, etc.)
  • Seizures
  • Abnormal physical movement 
  • Altered autonomic functions (breathing and heart rate)
  • Catatonia

 

When left undiagnosed and untreated, anti-NMDA receptor encephalitis can ultimately be fatal.

Diagnosis

While anti-NMDA receptor encephalitis remains difficult to diagnose, Dr. Dalmau and his colleagues created an acronym to help identify diagnostic clues when assessing a patient experiencing psychiatric symptoms that have come on suddenly. 

 

SEARCH for NMDAR-A covers the criteria:

  • Sleep dysfunction
  • Excitement
  • Agitation
  • Rapid onset
  • Child and young adult predominance
  • History of psychiatric disease absent
  • Fluctuating catatonia
  • Negative and positive symptoms
  • Memory deficit
  • Decreased verbal output
  • Antipsychotic intolerant
  • Rule out neuroleptic malignant syndrome (reaction to neuroleptic medications presenting with some similar symptoms)
  • Antibodies (and additional testing, including MRI, CSF studies, and electroencephalogram)

 

Following this diagnosis criteria, anti-NMDA receptor encephalitis may be more easily diagnosed, and diagnosed more quickly.

Treatment & Recovery

 

Treatment can vary depending on the specific case and the patient, but typically includes steroids, plasma exchange, intravenous immunoglobulin (extracted from the plasma in blood), and further immunotherapy medications.

 

If there is a tumor present, surgery and treatment on the tumor can help relieve symptoms. Supportive care with psychiatric treatment can also prove helpful.

 

The recovery can take months and, rarely, some patients experience dramatic recovery within the first few weeks which may indicate a different underlying condition.

 

The most severe symptoms typically resolve first but the behavioral and cognitive symptoms can take much longer to resolve, lasting up to a year or two in some patients.

Sources and More Information

 

Medscape, “Anti-NMDA Receptor Encephalitis or Primary Psychiatric Disorder?” https://www.medscape.com/viewarticle/929796

 

“Encephalitis” https://emedicine.medscape.com/article/791896-overview

 

“Intravenous Immunuglobulin” https://emedicine.medscape.com/article/210367-overview

 

NPR, “A Young Report Chronicles Her ‘Brain On Fire’” https://www.npr.org/2012/11/14/165115921/a-young-reporter-chronicles-her-brain-on-fire

 

OHSU, “Puzzling brain disease could now be better diagnosed, treated” https://news.ohsu.edu/2019/07/10/puzzling-brain-disease-could-now-be-better-diagnosed-treated

 

Perelman School of Medicine - University of Pennsylvania, “Anti-NMDAR Encephalitis” https://www.med.upenn.edu/autoimmuneneurology/nmdar-encephalitis.html

 

UC Santa Barbara - The Current, “Brain on Fire” https://www.news.ucsb.edu/2019/019546/brain-fire

 

U.S. National Library of Medicine, National Institutes of Health - PMC, “To Hell and Back Review: Brain on Fire: My Month of Madness” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3704309/

More from The Allied Times

POEMS Syndrome

 POEMS SyndromeThe rare blood disorder named for its symptoms.By Jenny Ewen, BA, NREMTEditor-In-ChiefPOEMS syndrome is a  rare blood disorder suspected to affect up to 5000 people in the USA, primarily men who are in later adulthood (around age 50). This syndrome damages the nerves and organs due to an increased number of abnormal plasma cells with…

Meet AMT: Dr. Ewen

Meet AMT: Dr. Ewen We interview our staff members for details on their EMS journey.When/why did you first become interested in becoming a doctor/working in the medical field? At the time I started to think about going to medical school I was an undergraduate with a major in psychology. I was interested in a career…

Meet AMT: Shannon Z.

Meet AMT: Shannon Z. We interview our staff members for details on their EMS journey.When/why did you first become interested in becoming an EMT/working in EMS?  Throughout my entire career spanning 30+ years, I have had many positions that required a safety background including OSHA, Workers Comp, Safety Committee Chair, Accident Investigations, etc. Being involved…

Alice in Wonderland Syndrome

 Alice in Wonderland SyndromeDistorted vision and perception suspected to be related to migraines – and thought to have inspired Lewis Carroll’s famous novel.By Jenny Ewen, BA, NREMTEditor-In-ChiefA 20-year-old man lies curled up in the fetal position on a bed in a hospital room. The neurologist asks the patient questions but all he can do is…

Just A Small Wound

Just A Small Wound An ER visit for a minor hand wound that turned into emergency surgery.By Marven Ewen, MDMedical DirectorIt was  an otherwise unremarkable afternoon in the ER, when a 26-year-old patient was brought in with an industrial injury. He had been working with an extremely high pressure hydraulic line that had a pinhole…

Can You Drink Too Much Water?

Can You Drink Too Much Water? With all the concern about hydrating enough, is it possible to overhydrate?By Mariah Xzena Briones, RMTCertification SpecialistAs the summer heat intensifies, staying hydrated becomes even more crucial for our health and well-being. While we are often reminded to drink enough water to avoid dehydration, it’s essential to strike a…

Are you ready to start saving lives?