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Psychosis From the Immune System: The Strange Case of Anti-NMDA Receptor Encephalitis · Understanding the Brain

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  Speaker 1: Welcome back. Today, a 21-year-old college student begins acting strangely.
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  Speaker 1: Her family first notices that she isn't sleeping and she
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  Speaker 1: becomes anxious and suspicious. Within days, she starts saying that
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  Speaker 1: people are watching her. Soon, she is hearing voices. There's
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  Speaker 1: no significant psychiatric history. She's been attending classes, spending time
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  Speaker 1: with friends, normally functioning. Now, she appears to be experiencing
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  Speaker 1: her first psychotic episode. The obvious possibilities that everybody will
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  Speaker 1: go to is schizophrenia. Some will go to bipolar with
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  Speaker 1: psychotic features or maybe substance-induced psychosis. But then something changes.
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  Speaker 1: Her movements become unusual. She develops involuntary facial movements and
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  Speaker 1: episodes of abnormal posturing. Her speech deteriorates. Suddenly, this does
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  Speaker 1: not look like a straightforward psychiatric case anymore. So what
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  Speaker 1: is one of the conditions the clinicians should be thinking
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  Speaker 1: about here? One possibility is anti-NMDA receptor encephalitis. The condition
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  Speaker 1: occurs when the immune system produces antibodies targeting NMDA receptors
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  Speaker 1: of the brain. These receptors play important roles in neural communication, learning, memory,
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  Speaker 1: and behavior. The amazing part is how the illness can begin.
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  Speaker 1: Some patients develop symptoms that can look strikingly psychiatric, anxiety, agitation, hallucinations.
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  Speaker 1: A young adult with no psychiatric history can therefore arrive
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  Speaker 1: at an emergency department appearing to have suddenly developed a
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  Speaker 1: major psychiatric disorder. But then the neurological signs emerge. Abnormal
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  Speaker 1: movements may appear. Speech can become impaired. Seizures can occur.
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  Speaker 1: Autonomic functions such as heart rate, blood pressure, or temperature
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  Speaker 1: can become unstable. In severe cases, patients can require intensive
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  Speaker 1: medical care. For clinicians, the challenge is recognizing when the
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  Speaker 1: pattern doesn't fit. Psychosis isn't itself particularly unusual in young adulthood,
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  Speaker 1: but rapidly progressing psychiatric symptoms accompanied by seizures, unusual movement abnormalities,
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  Speaker 1: and altered consciousness broaden the diagnosis. The investigation may involve
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  Speaker 1: neurological examination, EEG testing, brain imaging, cerebral spinal fluid analysis,
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  Speaker 1: and testing for specific antibodies. There is another important clue, though.
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  Speaker 1: Anti-NMDA receptor encephalitis can sometimes be associated with tumors, especially
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  Speaker 1: ovarian teratomas. When present, identifying and treating the tumor may
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  Speaker 1: become part of treating the neurological illness. This dramatically changes
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  Speaker 1: the treatment strategy. If clinicians assume the problem is exclusively psychiatric,
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  Speaker 1: antipsychotic medication might reduce certain symptoms but won't address the
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  Speaker 1: autoimmune process. Treatment can instead involve immunotherapies such as corticosteroids, intravenous, immunoglobin,
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  Speaker 1: with additional immune-directed treatments. The case illustrates something larger about
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  Speaker 1: psychiatric diagnosis. Behavior originates in the brain, which means diseases
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  Speaker 1: affecting the brain can sometimes first appear as changes in thought, emotion,
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  Speaker 1: or personality. Hallucinations don't automatically mean schizophrenia. Paranoia doesn't automatically
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  Speaker 1: mean a primary psychotic disorder. And bizarre behavior doesn't automatically
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  Speaker 1: mean The explanation belongs exclusively to psychiatry. Good diagnosis, therefore,
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  Speaker 1: resembles defective work. Clinicians develop an initial hypothesis, but they
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  Speaker 1: must remain willing to abandon it when new evidence appears.
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  Speaker 1: That's it for now.