Abstract
Background: N-methyl-D-aspartate (NMDA) receptor encephalitis is an autoimmune disorder historically associated with anti-NMDA receptor antibodies, predominantly described in young women with ovarian teratomas. This case presents a 4-year-old male with NMDA receptor encephalitis, highlights the importance of early detection and aggressive treatment of movement disorders in pediatric autoimmune encephalitis and contributes to the limited literature on the successful use of tetrabenazine for symptomatic control in children.
Case Report: A 4-year-old male presents refractory seizures, neuropsychiatric symptoms, and severe movement disorders. Initial EEG and brain MRI had unremarkable findings, the patient later exhibited focal slowing in the right parieto-occipital region, persistent buccal dystonia, athetotic hand movements, spasticity, and choreiform activity of the mouth and extremities. Additional symptoms included inattentiveness, sluggish pupillary response, and upward gaze nystagmus. Despite initial treatment with levetiracetam, the patient experienced progressive symptoms, including psychosis, aphasia, and further seizure activity. Video EEG revealed generalized slowing, focal onset seizures, and delta brushes. NMDA receptor antibodies were identified in both CSF and serum samples. Treatment with rituximab and tetrabenazine led to significant symptomatic improvement, with complete recovery achieved after two years and no subsequent relapses.
Discussion: This case underscores the diagnostic and therapeutic challenges of NMDA receptor encephalitis in pediatric populations, particularly in males with atypical presentations. It highlights the importance of early diagnosis, comprehensive management, and the potential efficacy of tetrabenazine for control of choreiform movements in children with autoimmune encephalitis. This report adds valuable insight to the limited literature on pediatric NMDA receptor encephalitis and its successful treatment outcomes.
Keywords
NMDA receptor encephalitis, Rituximab, Tetrabenazine, Neuropathology, Pediatric Neurology