Autoimmune Encephalitis: An Unusual Presentation as Nonconvulsive Status Epilepticus

Abstract

When refractory status epilepticus (RSE) occurs in an individual without any history of epilepsy and no immediate underlying etiology is found, it is referred to as new-onset refractory status epilepticus (NORSE). This clinical scenario may be notoriously difficult to treat and does not respond to initial medications. In cases of NORSE in which an etiology is found, antibody-mediated disorders are the most common cause. Autoimmune encephalitis refers to a diverse group of neuropsychiatric disorders and can present with an array of symptoms many of which make diagnosis difficult due to similarities in clinical, imaging, and laboratory findings with respect to other forms of autoimmune or infectious encephalitis. This case report highlights how a patient with acute-onset history, showing generalized periodic epileptiform discharges on electroencephalogram (EEG) but with no prior history of seizures, was eventually diagnosed as autoimmune encephalitis based on clinical findings, cerebrospinal fluid (CSF) reports, and EEG analysis.