An Evidence-Based Approach to Diagnosis and Prognosis in a Young Woman with New-Onset Super-Refractory Status Epilepticus: A Case Report

New-onset refractory status epilepticus (NORSE) is a rare clinical diagnosis. Autoimmune encephalitis and paraneoplastic encephalitis are the most common identifiable etiologies of NORSE; of the known autoimmune encephalitides, <200 cases of GAD65-related epilepsy have been reported in the literature. We describe a case of a 24-year-old female who presented with confusion and myoclonus. Electroencephalogram revealed NORSE that evolved into super-refractory status epilepticus. Her CSF showed a mild lymphocytic pleocytosis, and her MRI demonstrated changes in the bilateral temporal lobes. She was ultimately diagnosed with GAD65 autoimmune encephalitis and treated with immune-modulating therapy. This case highlights the complex diagnostic workup of patients with NORSE and the utility of validated prediction models for diagnosis and prognosis. While maintaining a broad differential, the patient’s Antibody Prevalence in Epilepsy (APE) score was a helpful clinical tool to support the pursuit of an autoimmune etiology. We also underline the need to concomitantly treat patients quickly during diagnostic workup because earlier treatment increases the Response to Immunotherapy in Epilepsy (RITE) score, indicating a more favorable prognosis.