perampanel and Encephalitis

Anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor encephalitis is an anti-neuronal surface antigen autoimmune encephalitis and is relatively rare. Our study evaluated a patient who developed anti-AMPA2 receptor encephalitis with memory deficits and refractory focal seizures as paroxysmal jerking on right face as well as dystonic seizure on right hand. On this patient, the combination treatment of levetiracetam, carbamazepine, and clonazepam, monthly periodic intravenous immunoglobin and immunosuppressive therapies for 5 months was not effective for the focal seizures, while his memory loss was slightly improved. However, adjunctive perampanel treatment led to a rapid relief of seizures. Perampanel is suggested in seizures associated with anti-AMPA receptor encephalitis by directly attenuating nerve hyperexcitability caused by glutamate and Ca2+-permeable GluA4 subunit of AMPA receptors.

Topics: Anticonvulsants; Encephalitis; Humans; Nitriles; Pharmaceutical Preparations; Pyridones; Seizures; Treatment Outcome

Epilepsia partialis continua (EPC) is a form of focal motor status epilepticus, associated with multiple etiologies. Etiology-specific treatments, such as hemispherotomy for Rasmussen encephalitis, lesionectomy for focal cortical dysplasia, and metabolic correction for non-ketotic hyperglycemia, have proven to be efficacious in treating EPC, but, in general, EPC is difficult to treat and often drug-resistant, and there is little evidence to guide therapy. We report the successful treatment of EPC with perampanel in two pediatric patients. The first patient was a 12-year-old boy with neuronal ceroid lipofuscinosis (NCL) who started to have EPC around the age of 10 years, characterized by left hemifacial myoclonic twitches and hemi-body jerks that were almost continuous throughout the day and disappeared during sleep. He had failed several antiepileptic drugs (AEDs). The EPC stopped within three days of initiating perampanel. The second patient was a six-year-old boy with POLG-related mitochondrial disease who presented to the emergency room with continuous jerky movements of the right arm and face after a trivial head injury. After failing several AEDs, including a midazolam drip, the EPC was controlled with perampanel. Both patients showed dramatic improvement and continue to show sustained efficacy after around five months of follow-up. Based on our observations, perampanel, which has a unique mechanism of action, appears to be a promising therapeutic option for treating EPC. [Published with video sequence].

Topics: Anticonvulsants; Child; Dyskinesias; Electroencephalography; Encephalitis; Epilepsia Partialis Continua; Humans; Male; Nitriles; Pyridones