Autoimmune Encephalitis in Long-Standing Schizophrenia: A Case Report

Area of Science:

• Neuroimmunology
• Psychiatry
• Autoimmune Disorders

Background:

• Anti-N-methyl-D-aspartate (NMDA) receptor antibody-mediated encephalitis is a severe autoimmune neurological disorder.
• It is characterized by antibodies against NMDA receptors in the central nervous system, leading to neuropsychiatric symptoms.
• While initially associated with young women and teratomas, it's now recognized as heterogeneous, affecting all demographics.

Observation:

• This case report details a 67-year-old male with a 40-year history of severe, treatment-refractory schizophrenia.
• His condition worsened during hospitalization, prompting a diagnostic re-evaluation.
• Extensive investigations, including an autoimmune panel, were performed.

Findings:

• The patient tested positive for anti-NMDA receptor antibodies in both serum and cerebrospinal fluid.
• Treatment with intravenous immunoglobulin and methylprednisolone resulted in rapid symptom improvement.
• This represents a rare instance of anti-NMDAR encephalitis presenting as long-standing schizophrenia.

Implications:

• This case underscores the importance of considering autoimmune encephalitis in treatment-refractory psychiatric conditions.
• Vigilance is needed for atypical features like seizures, autonomic dysfunction, or focal neurology.
• It highlights the potential for misdiagnosis and the need for broader diagnostic considerations in chronic psychiatric presentations.