2026 American Academy of Neurology Autoimmune Abstract Website

Objective:

To systematically evaluate treatment approaches and outcomes for movement disorders in neuronal antibody-mediated autoimmune encephalitis and to characterize their heterogeneity across antibody subtypes.

Background:

Autoimmune encephalitis (AE) is an increasingly recognized cause of non-infectious encephalitis, presenting with neuropsychiatric and movement disorder features across all age groups. Although movement disorders are a prominent component of the clinical phenotype, their management is inconsistently described, and treatment strategies have not been systematically evaluated.

Design/Methods:

MEDLINE and PubMed were systematically searched for observational studies published up to December 6, 2025. Studies including adult or pediatric patients with laboratory-confirmed neuronal cell-surface or synaptic antibody AE were included, while those lacking extractable data or relevant outcomes were excluded. Two independent reviewers conducted screening with consensus-based conflict resolution. The Joanna Briggs Institute critical appraisal checklist was used for data extraction and risk-of-bias assessment. Of 588 records identified, 106 duplicates were removed, leaving 482 records screened, 143 full-text articles assessed, and 121 studies included.

Results:

Across 121 studies comprising 2,748 patients, most employed a stepwise immunotherapy approach, with first-line treatments including corticosteroids, IVIG, and plasma exchange, followed by escalation to rituximab or cyclophosphamide where necessary. Symptomatic therapies (antiepileptics, benzodiazepines, dopamine-depleting agents) and tumor resection in paraneoplastic cases were also widely used. The most common movement disorder phenomenology were dystonia (47%) and chorea (33%), with distinct antibody-specific patterns. Partial response was the most frequent outcome (55%), followed by complete resolution (35%), no response (17%), and clinical worsening (16%). Complete-resolution rates were highest in LGI1 (62%, n=8) and anti-NMDA receptor encephalitis (43%, particularly in pediatric and tumor-associated cases), and lowest in IgLON5 disease (5%).

Conclusions:

These findings support early, individualized, stepwise immunotherapy as the optimal management strategy for movement disorders in AE. Standardized outcome reporting and longer-term follow-up are needed to facilitate timely treatment initiation and improve long-term outcomes.