Anti-CASPR2 Antibody-Associated Autoimmune Encephalitis Presenting as Refractory Seizures.

Autoimmune encephalitis (AE) is a rare immune-mediated disorder comprised of non-infectious neuroinflammatory disease processes. Clinical presentation overlaps with a broad range of neurodegenerative disorders and infectious encephalitis; therefore, AE remains a diagnosis of exclusion. Patients may present with nonspecific symptoms such as psychiatric disturbances, cognitive deficits, seizures, movement disorders, and confusion. Prompt diagnosis and management are necessary for patients with AE to decrease mortality and improve quality of life. First-line therapy includes immunosuppression with corticosteroids, intravenous immunoglobulin, and plasmapheresis. We report the case of an 86-year-old female with a medical history of Parkinson's disease who presented with nonspecific seizure-like activity and was diagnosed with AE.