[A case of new-onset refractory status epilepticus (NORSE) with an autoimmune etiology]

A 23-year-old man presented tonic-clonic seizure a week after an episode of antecedent infection. Although several anticonvulsants were used, convulsive attacks were not resolved and intravenous anesthetics were used to stop status epileptics. After combination of immunotherapies (high-dose intravenous methylprednisolone, immune absorbance and intravenous immunoglobulin (IVIg) therapies), frequency of convulsive attacks decreased, however, disturbance of consciousness was not recovered. All anti-neuronal antibodies tested were negative. Indirect immunofluorescence using the serum and rat brain section revealed positive signals in cytoplasm and nucleus in hippocampal neurons, strongly suggesting that this case has an autoimmune pathogenesis. The clinical features and course of this patient are well consistent with those in new-onset refractory status epilepticus (NORSE). The result of immunohistochemical analysis supports the hypothesis that NORSE has an autoimmune pathomechanism.