ANTI-NMDA RECEPTOR ENCEPHALITIS: A CHALLENGE IN PSYCHIATRIC SETTINGS
Authors: Kanniah *Guna Sekaran , Subramaniam Ganesh , Kumar Rishi 
Published: February 2025

Background

Anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis is a condition that was only identified relatively recently. It often presents in psychiatric settings, with clinical presentations that may overlap with those of other psychiatric disorders such as psychoses secondary to schizophrenia, substance use, or brief delusional disorder. It often presents in women of child bearing age and has a relatively high mortality rate. The treatment approach for anti- NMDA receptor encephalitis is considerably different from that used for other psychiatric and neurological conditions. Early recognition, correct diagnosis, and appropriate management of the condition are of vital importance to the prognosis, including reducing mortality rate, admissions to intensive care units, recurrence, complications of the disease and in some cases, irreversible hippocampal damage.

Case report, discussion and management: We present a case that highlights the typical presentation of anti-NMDA receptor encephalitis in a young woman and discuss management and outcome.

The N-methyl-Daspartate (NMDA) receptor, which is involved in memory, has also been implicated in the etiology of schizophrenia. While previously not wellknown, there is increasing awareness of anti- NMDA receptor encephalitis as a presentation of otherwise unexplained psychosis in emergency settings. Anti-NMDA receptor encephalitis is an autoimmune disease where the body attacks the receptors. It can present with an array of symptoms, but commonly patients experience psychosis (delusions, disorganization, hallucinations), catatonia, cognitive deficits, movement disorders, altered sensorium, and speech deficits It is 4 times more common in women, and, in over half of the cases, patients present with an ovarian teratoma. The diagnosis can be confirmed with antibodies in the cerebrospinal fluid, as well as changes on magnetic resonance imaging (MRI) and electroencephalogram (EEG). Given the nature of the symptoms and how the disease can mimic a primary psychotic episode, and the high morbidity and mortality associated with this condition, it is important to notice the atypical symptoms of anti-NMDA receptor encephalitis and test appropriately (imaging, EEG, antibody testing) to ensure patients get rapid treatment

References

1.Kamperman A, Veldman-Hoek M, Wesseloo R, et al. Phenotypical characteristics of postpartum psychosis: a clinical cohort study. Bipolar Disord. 2017;19:450–457.

2.Sachdev P, Mason C, Hazdi-Pavlovic D. Case-control study of neuroleptic malignant syndrome. Am J Psychiatry. 1997;154:1156–1158.

3.Duggal H, Fetchko J. Serotonin syndrome and atypical antipsychotics. Am J Psychiatry. 2002;159:672–673.

4.Dalmau J, Bataller L. Limbic encephalitis: the new cell membrane antigens and a proposal of clinical-immunological classification with therapeutic implications. Neurologia. 2007;22:526–537.

5.Ford B, McDonald A, Srinivasan S. Anti-NMDA receptor encephalitis: a case study and illness overview. Drugs Context. 2019;8:212589.

6.Barry H, Byrne S, Barrett E, et al. Anti-N-methyl-Daspartate receptor encephalitis: review of clinical presentation, diagnosis and treatment. BJPsych Bull. 2015;39:19–23.

7.Graus F, Titulaer M, Balu R, et al. A clinical approach to diagnosis of autoimmune encephalitis. Lancet Neurol. 2016;15:391–404.

8.Granerod J, Ambrose H, Davies N, et al. Causes of encephalitis and differences in their clinical presentations in England: a multicentre, population-based prospective study. Lancet Infect Dis. 2010;10:835–844.

9.Najjar S, Steiner J, Najjar A, et al. A clinical approach to new-onset psychosis associated with immune dysregulation: the concept of autoimmune psychosis. J Neuroinflammation. 2018;15:40.

10.Wandinger K, Saschenbrecker S, Stoecker W, et al. Anti- NMDA-receptor encephalitis: a severe, multistage, treatable disorder presenting with psychosis. J Neuroimmunol. 2011;231:86–91.

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