Authors :
Presenting Author: Soo Hyun Ahn, MD – Seoul National University Hospital
Yoonhyuk Jang, MD – Neurology – Seoul National University Hospital; Bum-Sup Jang, MD, PhD – Radiation Oncology – Seoul National University Hospital; Han Sang Lee, MD – Neurology – Seoul National University Hospital; Jae-Han Bae, MD – Neurology – Asan Medical Center; Yoon-Kyung Lee, MD – Neurology – College of Medicine, Dong-A University; Jun-Sang Sunwoo, MD – Neurology – Soonchunhyang University Seoul Hospital; Jin Sun Jun, MD – Neurology – Kangnam Sacred Heart Hospital; Tae-Joon Kim, MD – Neurology – Ajou University School of Medicine; Keun Tae Kim, MD – Neurology – Keimyung University School of Medicine; Kon Chu, MD, PhD – Neurology – Seoul National University Hospital; Sang Kun Lee, MD, PhD – Neurology – Seoul National University Hospital; Soon-Tae Lee, MD, PhD – Neurology – Seoul National University Hospital
Rationale:
New-onset refractory status epilepticus (NORSE) is a devastating condition with high mortality rates in the acute phase and long-standing epilepsy in the chronic phase (Epilepsia 2022;63(11):2827-2839). Early immunotherapies are often recommended (Epilepsia 2022;63(11):2827-2839). While about half of NORSE are cryptogenic (C-NORSE) (Neurology 2015;85(18):1604-13), the pathogenic spectrum and clinical dynamics of C-NORSE are not well-characterized. This study aimed to analyze the comprehensive multi-dimensional spectrum of C-NORSE, including clinical presentation, acute response and long-term clinical course after immunotherapy, brain image parameters, CSF biomarkers, and genomic susceptibility.
Methods:
From an institutional prospective cohort for autoimmune encephalitis diagnosis study, consecutive patients with NORSE treated at Seoul National University Hospital from January 1, 2013, to March 31, 2023 were extracted, given that all NORSE patients were screened for autoantibody diagnostic tests. Variable clinical measures and immunotherapy details were included, in addition to modified Rankin Scale (mRS), the Clinical Assessment Scale in Autoimmune Encephalitis (CASE), seizure frequency (defined as times per month), and the number of prescribed anti-seizure medications, followed up to 24 months. For pathogenomic studies, peripheral blood immune-regulatory genes and CSF were analyzed using whole-genome sequencing and ELISA.
Results:
Out of 139 patients diagnosed with NORSE, a total of 83 patients (59.7%) were identified as C-NORSE. After excluding nine patients with insufficient data, 74 patients were included in the final analysis. The median age was 38 years (IQR, 23.7-50.0), and 36 patients (48.6%) were male. Fever was reported as a prodromal symptom in 58 patients (78.4%), and 14 patients (18.9%) presented with non-convulsive status epilepticus. A total 73 patients received first-line agents (corticosteroids, intravenous immunoglobulins) within a median of two days (IQR, 0-7.0) after the onset of NORSE. Sixty-four patients (86.5%) received second-line immunotherapy, including 60 receiving rituximab (81.1%), 43 receiving tocilizumab (58.1%), and 39 receiving both (52.7%). The initial clinical factors