The incidence of new-onset refractory status epilepticus in the patients with encephalitis

Abstract

New-onset refractory status epilepticus (NORSE) is a rare clinical presentation which patients without a history of epilepsy suddenly developed prolonged seizures that do not respond to at least two standard anti-convulsant medications (NORSE INSTITUTE). The etiology of the disease state is various including autoimmune and paraneoplastic encephalitis. To clarify the incidence of NORSE, we examined the clinical history of the patients with encephalitis who entered to our center from 2000 to 2019. Of 102 patients with encephalitis (age: 55±21, 52 male, 50 female), seven (6.9%, age: 28±6, 1male, 6 female) showed intractable epilepsy which required the continuous infusion of midazolam, propofol and barbiturates in the intensive care unit. Six cases showed a febrile illness for 1-7 days prior to the onset of the seizure. In the flair MRI imaging, there were the high intensity signal in the claustrum of four. In two patients, the high intensity signal was observed in the medial temporal lobe. Two patients died. The seizures of five were controlled by two or more antiepileptic drugs but the higher brain dysfunction was apparent when they were discharged from our center. Of 7 patients, a 31-year-old woman was thought to be NORSE. Her seizure onset was very rapidly progressive and the single seizure was prolonged until the continuous intravenous anesthetics was fully treated. NORSE is rare, but the patients with similar clinical characteristics might be more common. The awareness of the NORSE is needed from early because of the prognosis is bad.