CASE OF AUTOIMMUNE ENCEPHALITIS ASSOCIATED WITH ANTI-NMDA RECEPTOR ANTIBODIES

Background. Anti-NMDA receptor encephalitis is an autoimmune disorder of the central nervous system characterized by antibodies directed against the GluN1 subunit of the NMDA receptor. The disease most commonly affects children and young women and often presents with psychiatric and seizure manifestations that can mimic viral encephalitis or acute psychosis. Although considered rare, timely recognition is essential, as early initiation of immunotherapy is closely associated with favorable outcomes and reduced risk of relapse.

Case description. We report a clinical case of a 16-year-old female patient admitted with her first episode of generalized tonic-clonic seizures and marked behavioral changes. The medical history revealed a preceding two-week period of increasing fatigue, sleep disturbances, and episodes of disorientation. Initial clinical suspicion was postinfectious encephalitis; however, infectious causes were excluded after extensive testing. Brain MRI demonstrated bilateral inflammatory changes in the hippocampi, and cerebrospinal fluid analysis revealed the presence of anti-NMDA receptor antibodies, confirming the diagnosis of anti-NMDA receptor encephalitis. The patient received immunotherapy, including high-dose intravenous corticosteroids and intravenous immunoglobulin. This resulted in a rapid clinical improvement with complete recovery of cognitive and motor functions, cessation of seizures, and normalization of sleep.

Conclusion. This case illustrates the typical course of anti-NMDA receptor encephalitis in adolescents and emphasizes the need for high clinical vigilance in patients presenting with a combination of psychiatric symptoms and seizures without evidence of infection. Detection of antibodies to the NMDA receptor in cerebrospinal fluid remains the diagnostic gold standard. Early initiation of immunotherapy significantly improves functional outcomes and prevents fatal outcomes. A comprehensive, multidisciplinary approach involving neurologists, psychiatrists, and immunologists is essential for the successful management of patients with autoimmune encephalitis.

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