<p>Anti-N-methyl-D-aspartate receptor encephalitis mimics neuroleptic malignant syndrome: case report and literature review</p>

Abstract

Background Anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis is a severe autoimmune disease characterized by complicated psychiatric and neurological symptoms and a difficult diagnosis. This disorder is commonly misdiagnosed, and diagnosis is often delayed. The clinical signs can mimic other psychiatric abnormalities, such as neuroleptic malignant syndrome (NMS) that is usually caused by antipsychotic exposure. This fact raises the question of whether the symptoms common to NMS are due to anti-NMDA receptor encephalitis or established NMS. Cases presentation We describe a rare case of a 29-year-old male without psychiatric history who initially presented with a fever, altered consciousness, behavioral changes, rigidity, and elevated creatine kinase. He was initially diagnosed with NMS. NMS-like symptoms did not improve with active treatments and disappeared for a long period after discontinuing antipsychotics. The patient gradually developed a complicated disease progression, including speech impairment, mutism, and movement disorders, and symptom progression led to the final diagnosis of anti-NMDA receptor encephalitis. The related pathophysiological mechanisms, clinical features, and treatment of this disease are reviewed. Conclusion We highlight that the natural progress of anti-NMDA receptor encephalitis can mimic the symptoms of NMS and NMS-like features could be due to anti-NMDA receptor encephalitis upon antipsychotic exposure, and not true NMS. Clinically, the suspicion of NMS may serve as a significant alarm to suspect anti-NMDA receptor encephalitis and lead neurologists or psychiatrists to investigate such a diagnosis.

Steroid-responsive Encephalopathy as a Semblance of Neuroleptic Malignant Syndrome in a Patient with Schizophrenia

“…Although CSF, EEG, and neuroimaging profile were not conclusive for an autoimmune encephalitis, which may occur due to a range of factors, [8][9][10] the presence of cerebral small-vessel disease too suggested a primary immune-based vasculitis and encephalitis. The presentation in the index patient remarkably differed from the previously reported cases which had a younger age of onset of illness, [2][3][4][5][6] had a female predominance, [2,3,5,6] and had a seizure or other neurological symptoms at the initial presentation. [2,3,6] The nonevaluation of a panel of other autoantibodies was a limitation in this case, and a definitive diagnosis based on a brain biopsy was not feasible.…”

“…Although various neuropsychiatric symptoms are the common initial presentation in autoimmune encephalopathies, semblance to the neuroleptic malignant syndrome (NMS) is rarely reported. [2][3][4] Moreover, it is a very uncommon observation that autoimmune encephalitis, which has usually an acute and progressive course of illness, presents as an episodic mental illness with a long interepisodic interval. Only two case reports of autoimmune encephalitis are available wherein a diagnosis was made after a long history of relapsing psychosis or mood disorder.…”

“…Besides neurological symptoms, CPM may also present with neuropsychiatric symptoms such as personality changes, inappropriate affect, emotional lability, disinhibition, catatonia, psychosis, and delirium, as described in some reports. [2][3][4] None of the previous reports have suggested an occurrence of prominent manic symptoms followed by catatonia in patients with central pontine/extrapontine myelinolysis (CPEM). We describe a unique case of an elderly man with such a presentation after rapidly corrected hyponatremia.…”

Fatal Autoimmune Anti-NMDA-Receptor Encephalitis with Poor Prognostication Score in a Young Kenyan Female

“…Our adolescent patient’s clinical course followed what is recognised to be more common in children affected by NMDARE, ie, abnormal movements, insomnia, and irritability with progression to coma within 4 weeks. 1 Her initial presentation being diagnosed as a primary psychiatric disease is not unusual, including NMDARE mimicking NMS, 8 but did lead to some delay in reaching the diagnosis. In our setting, infective and inflammatory causes of encephalitis are more common, and therefore feature in our institutional encephalitis management protocol which we have previously demonstrated to expedite NMDARE diagnosis in an expatriate patient, who eventually had a very good clinical outcome.…”

Not Your Average Seizure: A Case of N-Methyl-D-Aspartate Receptor Encephalitis and Review of Literature

“…The diagnosis of NMDA receptor encephalitis can be challenging. Oftentimes, nonspecific and predominant neuropsychiatric symptoms may lead to misdiagnosis of a psychiatric disorder [3]. Neuropsychiatric sequelae are a potential problem due to delay in diagnosis as most patients are treated for infectious etiologies [4].…”