Anti-LGI1 encephalitis causing faciobrachial dystonic seizures

Anti-leucine-richglioma inactivated protein 1 (LGI1) encephalitis has an autoimmune origin and can be reversed with immunotherapy. It is obvious that identifying and treating this condition early is of paramount importance. We present the case of a 69-year-old man who was admitted to hospital with faciobrachial dystonic seizures and was found to have antibodies to LGI1. His symptoms started approximately 3 months prior admission to the hospital. There had also been some subtle cognitive impairment. He was treated with two courses of intravenous immunoglobulin and commenced on prednisolone 50 mg daily and clonazepam 500 µg at night. Despite these treatments, his seizures were becoming progressively more frequent and severe. He then underwent treatment with a course of plasma exchange followed by an intravenous infusion of methylprednisolone and returned to his previous baseline function.