Rationale:
Childhood absence epilepsy (CAE) is one of the most common forms of pediatric epilepsy. It is a common generalized epilepsy syndrome with a presumed genetic cause, characterized by typical absence seizures (TAS) appearing in otherwise healthy school-aged children. Ethosuximide is recommended as first-line therapy in most children with CAE with valproate and lamotrigine as alternatives in patients who do not tolerate first line therapy. We propose the consideration of Amantadine as an additional option for refractory CAE.
Methods:
We present a case of an 11-year-old male diagnosed with CAE presenting to clinic for transfer of care. By history, patient presented with a generalized tonic clonic seizure (GTC) at 4 years of age followed by repeated absence seizures confirmed on EEG leading to the diagnosis of CAE. On presentation, patient had a VNS in place, failed valproate, lamotrigine, levetriacetam, topiramate, carbamazepine and lastly phenytoin with worsening of his absence seizures, which prompted presentation to clinic. EEG was abnormal with abundant 3 Hz generalized spike and slow waves concerning for absence status epilepticus. He was given IV lorazepam, loaded with IV valproic acid and IV levetriacetam. The EEG improved initially but later worsened again. Patient was discharged on levetiracetam and valproic acid but had increased recurrence of GTC's so was readmitted. It was concluded that valproic acid made him worse (failed x2) and was switched to clobazam. He continued to report absence seizures and GTC's. Therefore, zonisamide was added with some improvement. Repeated MRI Brain, LP to rule out GLUT1 deficiency and comprehensive metabolic workup was unremarkable. Genetic testing revealed he was a POLG carrier, otherwise unremarkable. On discharge, we started amantadine as a trial to see if would help with his absence seizures while continuing levetriacetam, zonisamide, and clobazam.
Results:
Following the addition of amantadine, no reports of any clinical events or concerns. No absence seizures or GTC's. Patient was more awake, alert, and energetic. Repeat routine EEG at the 12-week mark was normal for age, which was his first in years. He was weaned off levetiracetam and gradually weaned off clobazam with no clinical issues or concerns while continuing to be on zonisamde and amantadine for the time being. Patient has been seizure free for about 1.5 years.
Conclusions:
While multicenter randomized, double-blind trials are needed to prove its safety and efficacy, we propose consideration of amantadine as an add-on drug for children with absence epilepsy refractory to multiple medications. Funding: None