Neuropsychiatric manifestations of anti‐N‐methyl‐D‐aspartate receptor encephalitis in a 14‐year‐old female: A case report

Key Clinical Message This case underscores the critical importance of timely recognition and management of NMDAR encephalitis in adolescents to mitigate potential long‐term sequelae. If a pediatric patient presents with suspected viral encephalitis, autoimmune etiology must be excluded via cerebrospinal fluid antibody assay to guide appropriate immunosuppressive therapy, and improve patient outcomes. Autoimmune encephalitis particularly involving the n‐methyl‐d‐aspartate receptor (NMDAR) is recognized as a rare cause of acute encephalopathy in pediatric patients. The following case is of a 14‐year‐old female diagnosed with anti‐NMDAR encephalitis who initially presented with fever, episodic convulsions, and loss of consciousness. She subsequently developed right‐sided body weakness, expressive aphasia, and visual hallucinations. Clinical examination revealed prominent neuropsychiatric manifestations such as altered sensorium, motor deficits, hallucinations, and visual disturbances. Cerebello‐bulbar signs were not appreciable in this particular case. She was treated for viral encephalitis but showed no improvement. Laboratory investigations revealed the presence of NMDAR antibodies in the cerebrospinal fluid confirming the diagnosis of autoimmune etiology. The patient demonstrated notable improvement following immunosuppressive treatment.