ペランパネルが発作および行動異常に共に著効したLennox―Gastaut 症候群の 1 例

Perampanel (PER) is a new antiepileptic drug (AED) and a selective non―competitive antagonist against the α―amino―3―hydroxy―5―methyl―4―isoxazolepropionic acid (AMPA) receptor. The effects of PER on Lennox―Gastaut syndrome (LGS) have not been established, and because of its adverse effects of irritability, detrimental effects on cognition and behavior should be anticipated upon its usage for LGS. We report a 22―year―old male patient who had West syndrome at 5 months of age and whose epilepsy was thereafter very resistant to ACTH therapy and numerous AEDs. Tonic seizures began to occur at 2 years of age with the appearance of slow spike―wave complexes and generalized paroxysmal fast activity on electroencephalogram (EEG), which indicated a transition from West syndrome to LGS. At 5 years of age, behavior disorders such as irritability and violent aggressiveness emerged. Occasional focal impaired awareness seizures and myoclonic seizures began at 9 years of age. At 18 years of age, PER was cautiously introduced with a dramatic reduction of seizure frequency and associated improvement of behavioral disorders. In this case, we believe that the amelioration of irritability and aggressive behavior was brought about by the decrease of seizure frequency through the antiepileptic effects of PER, despite its potential to cause irritability.