NORSE secondary to anti-GAD65 antibody-positive encephalitis treated with novel adjunctive rapid titration VNS protocol.

Abstract

New Onset Refractory Status Epilepticus (NORSE) is a rare and severe condition characterized by refractory seizures in individuals without a prior history of epilepsy. This case report describes a 37-year-old woman diagnosed with anti-glutamic acid decarboxylase 65 (anti-GAD65) antibody-positive encephalitis-related NORSE. Her seizures were refractory to multiple interventions, including anti-seizure medications, anesthetics, immunotherapies, a ketogenic diet, and electroconvulsive therapy. Seizures recurred twice during the tapering of anesthetic medications. However, after 32 days of treatment, the seizures were successfully controlled. To maintain seizure control and facilitate the weaning of anesthetics, a Vagus Nerve Stimulator (VNS) was implanted using a novel rapid titration protocol. This allowed for the successful tapering of anesthetics by day 50, with no recurrence of seizures. At her 9-month follow-up, the patient remained seizure-free and had an improved quality of life. This case highlights that early initiation of immunosuppressive treatment may lead to a favorable prognosis. The novel application of VNS therapy assisted seizure control in NORSE, thus encouraging further research investigating the potential role of VNS in this condition. PLAIN LANGUAGE SUMMARY: New Onset Refractory Status Epilepticus (NORSE) is a rare and severe condition characterized by relentless seizures in individuals without a prior epilepsy history. This report shares the case of a 37-year-old woman with NORSE, associated with a high anti-glutamic acid decarboxylase 65 antibody titer. Her seizures were super-refractory, requiring multiple anti-seizure medications, anesthetics, immunotherapies, a ketogenic diet, and electroconvulsive therapy. Seizures recurred twice during the tapering of anesthetic medications. However, by hospital day 32, the seizures were successfully controlled with these interventions. To further stabilize seizure control and enable the successful discontinuation of anesthetics, a Vagus Nerve Stimulator (VNS) was implanted. The patient had no further seizures and gradually recovered back to her pre-disease baseline. This case suggests that a novel rapid VNS titration protocol could be a promising treatment option for NORSE, warranting further investigation.