Category: Pediatric Movement Disorders
Objective: Our aim was to investigate clinical characteristics and evolution of movement disorders (MD) in pediatric anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis.
Background: Movement disorders account for 95% of pediatric anti-NMDAR encephalitis. They are probably due to extrasynaptic NMDAR hyperfunction without direct involvement of basal ganglia. MD are usually hyperkinetic and complex but classically have a good response to immunotherapy.
Method: We conducted a retrospective descriptive monocentric study including a cohort of pediatric anti-NMDAR encephalitis between 2001 and 2020. MD phenomenology and outcome, brain magnetic resonance imaging (MRI) findings, electroencephalogram (EEG) patterns and treatment were analyzed.
Results: A total of 14 patients, sex ratio (male/female)=0.55, ages were between 10 months-13 years. Ten patients had MD, 5 of which were mixed hyperkinetic movements. Orofacial dyskinesia was seen in 7 patients. Other MD included dystonia (n=6) and chorea (n=3). Concomittant epileptic manifestations were seen in 8 patients. Brain MRI was abnormal in 5 patients in the MD group, showing white matter hyperintensities (n=3), diffuse atrophy (n=1) or basal ganglia lesions (n=1). EEG was consistent with encephalopathy in 9 patients and showed background slowing (n=4) and/or epileptic discharges (n=6). Total clinical improvement after treatment was seen in 6 patients. Movement disorders resolved with immunotherapy in all patients except for one which had residual dystonia.
Conclusion: MD in anti-NMDAR encephalitis are common, especially in the pediatric population and must be clinically distinguished from epileptic manifestations. Their prognostic value in the clinical course is yet to be precised. New onset orofacial dyskinesia in a child with or without other neurological manifestations must raise high suspicion of anti-NMDAR encephalitis.
To cite this abstract in AMA style:
M. Jamoussi, H. Benrhouma, Z. Miladi, T. Ben Younes, H. Klaa, I. Kraoua, I. Ben Youssef, M. Ben Ahmed. Movement disorders in pediatric anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis [abstract]. Mov Disord. 2022; 37 (suppl 2). https://www.mdsabstracts.org/abstract/movement-disorders-in-pediatric-anti-n-methyl-d-aspartate-receptor-nmdar-encephalitis/. Accessed June 14, 2025.« Back to 2022 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/movement-disorders-in-pediatric-anti-n-methyl-d-aspartate-receptor-nmdar-encephalitis/