Abstracts

Rationale: To characterize the electrographic and clinical features associated with autoimmune epilepsies.

Methods: We performed a retrospective study, which included persons with epilepsies (18 years or older) who underwent serologic and/or cerebrospinal fluid (CSF) evaluation for neural autoantibodies at UCLA between 2015-2022.

Results: Demographics: A total of 165 persons with epilepsies (PWE) underwent autoantibody screening (female, n=91 (55%)) for suspected immune-mediated etiology. Mean age at the time of screening was 49.6±20.4 years (range 18-87). Seventy-seven patients had both CSF and serologic evaluations, 54 had only CSF testing, and 34 had only serologic testing. Antibody and CSF evaluations: Antibody screening was positive for 32 (19%) PWE. On CSF evaluation, most common antibody was anti-GAD65 Ab (N=5), followed by anti-AChR ganglionic Ab (N=1), anti-LGI1 Ab (N=1), and anti-NMDA Ab (N=1). On serum testing, low titer (< 2.00 nmol/L) anti-GAD65 Ab (N=16) was most common followed by high titer anti-GAD65 Ab (N=3). Four patients had low titer anti-GAD65 Ab and one other autoantibody (anti-AChR ganglionic Ab (N=2), anti N type Ca channel Ab (N=1), and anti VGKC Ab (N=1)). Other autoantibodies included anti-LGI1 Ab (N=1), anti-CASPR2 (N=1), anti N type Ca channel ab (N=1), anti-VGKC ab (N=1), and anti-AChR ganglionic Ab (N=1).