Reviewed and revised 8 July 2014
- Anti-NMDA Receptor Encephalitis is an under-recognised progressive neurological disorder caused by antibodies against NR1-NR2 NMDA receptors
- 60% of patients with anti-NMDA receptor encephalitis have the presence of a tumour (most commonly teratoma)
- Up to 90% of patients are female
- The disorder typically progresses over 1-2 weeks
- An initial non specific ﬂu-like prodrome (sub-febrile temperature, headache, fatigue)
- followed by a psychotic stage with bizarre behaviour, disorientation, confusion, paranoid thoughts, visual or auditory hallucinations and memory deﬁcits
- In the following phase, decreased consciousness, hypoventilation, lethargy, seizures, autonomic instability and dyskinesias develop
- evidence of a tumour (e.g. pelvic teratoma)
Diagnosis is often delayed due to resemblance to other conditions such as:
- Infectious encephalitides (particularly HSV and HHV-6)
- Other autoimmune etiologies (e.g. limbic encephalitis due to autoantibodies against Hu, Ma2, CV2 and amphiphysin)
- Neuroleptic malignant syndrome
- Lethal catatonia
- Cerebral space-occupying lesions
- Metabolic disorders – hyper/hypothyroidism, Cushing syndrome, Addison disease
- Psychiatric disorders – schizophrenia, psychotic depression, pseudo-seizures
- Drugs, toxins or withdrawal (e.g. ketamine, PCP, dextromethorphan, antipyschotic-induced movement disorders, etc)
- NR1 and NR2 antibodies in CSF combined with a characteristic clinical picture have 100% sensitivity and specificity
- pelvic ultrasound
- further tests to exclude other causes of encephalopathy
- Early removal of tumour if present
- Immunotherapy includes consideration of corticosteroids, intravenous immunoglobulin and plasma exchange therapy in severe cases
- supportive care and monitoring
- Early identification and removal of tumour is associated with better outcomes (<4 months from symptom onset)
- 47% Full Recovery
- 28% Mild stable deficits
- 18% Severe deficits
- 7% Death
References and Links
- Neurological Mind-boggler 011 — Medically cleared?
- Dalmau J, Tüzün E, Wu HY, Masjuan J, Rossi JE, Voloschin A, Baehring JM, Shimazaki H, Koide R, King D, Mason W, Sansing LH, Dichter MA, Rosenfeld MR, Lynch DR. Paraneoplastic anti-N-methyl-D-aspartate receptor encephalitis associated with ovarian teratoma. Ann Neurol. 2007 Jan;61(1):25-36. PMC2430743.
- Dalmau J, Gleichman AJ, Hughes EG, Rossi JE, Peng X, Lai M, Dessain SK, Rosenfeld MR, Balice-Gordon R, Lynch DR. Anti-NMDA-receptor encephalitis: case series and analysis of the effects of antibodies. Lancet Neurol. 2008 Dec;7(12):1091-8. PMC2607118.
- Graus F, Saiz A, Dalmau J. Antibodies and neuronal autoimmune disorders of the CNS. J Neurol. 2010 Apr;257(4):509-17. PMID: 20035430.
- Wandinger KP, Saschenbrecker S, Stoecker W, Dalmau J. Anti-NMDA-receptor encephalitis: a severe, multistage, treatable disorder presenting with psychosis. J Neuroimmunol. 2011 Feb;231(1-2):86-91. PMID: 20951441.
- Young PJ, Baker S, Cavazzoni E, Erickson SJ, Krishnan A, Kruger PS, Rashid AH, Wibrow BA. A case series of critically ill patients with anti- N-methyl-D-aspartate receptor encephalitis. Crit Care Resusc. 2013 Mar;15(1):8-14. PMID: 23432495.
FOAM and web resources
- TPR — Must-read: Anti-NMDA Receptor Encephalitis (2013)