Risk of long-term neuropsychiatric impairment in pediatric anti-NMDA receptor encephalitis (P3.197)

Objective: Characterization of functional outcomes in children with anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis. Background: Anti-NMDAR encephalitis presents with motor and neuropsychiatric symptoms. There is limited data describing outcomes in pediatric populations. Design/Methods: Retrospective study of patients presenting to Texas Children’s Hospital between 2010 and 2016. Results: Nineteen patients were identified. The cohort was predominantly female (74%), Hispanic (68%) or African American (32%), and presented at a mean age of 9.8 years (1.5–17.9 years). 89% presented with neuropsychiatric dysfunction (agitation, confusion, or psychosis). Movement disorders occurred in 12 (63%) and seizures in 11 (58%). All but 1 patient received both corticosteroids and intravenous immunoglobulin; 68% also received rituximab and 26% underwent plasma exchange. Mean duration of hospitalization was 38 days (6–128 days), with 47% requiring inpatient rehabilitation for a mean of 26 days (7–49 days). At discharge, 4 (21%) had complete recovery (normal mental status and neurological examination). The remaining 15 had neuropsychiatric deficits, including cognitive impairment, developmental regression, or mood dysregulation. Six (32%) also had chorea or impaired mobility. After discharge, patients were followed for a mean of 18 months (1–48 months), during which an additional 2 (11%) made full recovery. Three (16%) patients had residual motor symptoms at last follow-up. Eleven (58%) had neuropsychiatric impairments: 4 (21%) had attention deficits requiring stimulant medications, 5 (26%) had mood disorders (1 requiring inpatient psychiatric care), and 5 (26%) had cognitive impairments. Patients with residual cognitive or attention deficits at follow-up had a significantly longer initial hospitalization (mean 56 versus 26 days). Conclusions: A minority of pediatric patients with anti-NMDAR encephalitis exhibit complete recovery at initial discharge. While motor symptoms improved during the initial 18 months of follow-up, the majority had residual neuropsychiatric dysfunction. It is unclear whether impairments will dissipate or if dysfunction reflects residual damage that warrants ongoing assessment and need for educational and psychiatric support. Disclosure: Dr. Nunneley has nothing to disclose. Dr. Lotze has nothing to disclose. Dr. Muscal has nothing to disclose.