Up to 75% of AE patients see a psychiatrist first

We had the pleasure of having psychiatrist Stephen Rush, MD discuss the role of psychiatry in AE at our recent Midwest Support Group meeting. Dr. Rush is an Associate professor of Psychiatry and the Medical Director of Ambulatory Services at the University of Cincinnati Department of Psychiatry and Behavioral Neuroscience. In his practice he not only treats AE patients, but also provides education to fellow clinicians on diagnosis and management of AE. We have summarized his presentation, so you can learn more about the role of and challenges faced by psychiatrists in AE.

Many cases of autoimmune encephalitis are characterized by rapid symptom progression that include memory issues, movement disorders, seizures, insomnia, issues with speech, significant behavior changes, psychosis, and obsessive compulsive like symptoms. Up to 75% of AE patients see a psychiatrist or psychologist first for symptoms that may seem like a psychiatric disorder, according to Dr. Rush. Therefore, it is important for psychiatrists to differentiate between AE and primary psychiatric disorders like bi-polar disorder and schizophrenia.

Diagnosing AE is not an easy task. It is a relatively new disease with the first case study described in 2007 by Dr. Dalmau. Even though our understanding of AE is improving every day, there is still a lot we don’t know. AE is a rare disease impacting approximately 4,000 people each year who receive a diagnosis. There are roughly 30,451 practicing psychiatrists in the US, according to a 2018 report1 so not every psychiatrist will necessarily see an AE patient. All medical disciplines struggle with these challenges, but psychiatrists deal with additional challenges as well.

In 60% of patients that end up in a hospital due to AE, psychiatric symptoms are the most prominent symptoms seen. Psychiatrists are often the first to see patients that are suffering from AE. In about 59% of these patients, they see behavioral problems and in 17% psychosis; compared to 10% that show neurologic symptoms, and 6% that show cognitive symptoms. In an average course of AE, 80% of patients will experience behavioral symptoms, and 44% will experience psychosis at some stage of their disease. The challenge is that these symptoms can mimic primary psychiatric disorders, leading to misdiagnosis.

Symptoms an AE patient may experience:

Behavioral symptoms(found in 68% of patients) Agitation, Disorganized behaviors (no purpose), Pathologic laughter or smiling
Psychotic symptoms(found in 67% of patients) Auditory hallucinations, Visual hallucinations, Paranoid delusions
Mood symptoms(found in 47% of patients) Anxiety/panic, Mood instability with irritability, Mania, Depression
Catatonic symptoms(found in 30% of patients) Mutism, Stupor (not appearing present), Posturing (where patients can hold a posture for hours), Verbigeration (repetition of one word), Echolalia (repeats what you say, like having an echo)

Examples of psychiatric disorders that can mimic AE are bi-polar disorder, schizophrenia, major depression disorder, panic disorder, and mood disorder. Dr. Rush states that if we could define a commonly observed course in AE, it might be easier to recognize as AE instead of primary psychiatric disorder. There are four phases commonly seen as part of AE, from a psychiatrist point of view.

First, the prodromal phase, in which nonspecific cold or viral symptoms are described in 70% of the cases. Within two weeks of this phase, the psychotic phase develops. Some characteristics of this phase are emotional disturbance and prominent schizophrenia-like symptoms and amnesia. The unresponsive phase may look like catatonia and can involve catalepsy-like symptoms, and bizarre and inappropriate smiling. The patient does have normal brainstem reflexes but doesn’t respond to a visual threat.  And the last phase, the kinetic phase, looks like bi-polar mania. What may differentiate between the two, is that all patients gradually develop orolingual dyskinesias (lip licking or chewing) and intractable bizarre orofacial-limb dyskinesis (postures that they hold, for instance forceful clenching of the teeth, grimacing and uncoordinated eye movements). A complication in this differentiation is that these hyperkinetic movements vary in speed, distribution, and motor pattern.

As you can see, it not easy to differentiate between AE and primary psychiatric disorders, as these symptoms can present at different times and at a different intensity. In the diagnostic role of the psychiatrist, Dr. Rush has developed a protocol for how to manage first-episode psychosis at the in-patient psychiatric unit at UCHealth. Given that many patients with AE see a psychiatrist first in an in-patient setting, it is important to consider all diseases, as missing a diagnosis of AE can have potentially dangerous consequences. Everyone that presents with a first-episode pf psychosis or a severe mood disorder like mania (part of bi-polar disorder) – both of which can be seen in AE – will get the Mayo panel for AE upon admission combatting potential misdiagnosis.

Thank you Dr. Rush for your very informative presentation and for all you do for those affected by AE.

  1. “The Silent Shortage: A White Paper Examining Supply, Demand and Recruitment Trends in Psychiatry” by Merritt Hawkins. February 22, 2018