EARLY-CHILDHOOD PROGRESSIVE MYOCLONUS EPILEPSY PRESENTING AS PARTIAL SEIZURES IN DENTATORUBRAL-PALLIDOLUYSIAN ATROPHY

Purpose: We explored the characteristics of epileptic seizures of prog ressive myoclonus epilepsy (PME) in 2 brothers with dentatorubral-pall idoluysian atrophy (DRPLA). Methods: We obtained the case history of t he siblings and ictal and interictal EEGs. Postmortem examination or d emonstration of elongated CAG repeat in the gene for DRPLA was used to confirm the diagnosis. Results: Two Japanese siblings developed PME c haracterized by versive or himiclonic seizures with or without seconda rily generalized tonic-clonic convulsions. The elder brother regressed mentally and exhibited increasing spasticity after age 1 year. Myoclo nus and seizures developed at age 4 years. The younger brother had sho wn psychomotor retardation before age 4 years, when he began to deteri orate further neurologically as the elder brother had. He also develop ed myoclonus and seizures at that age. Seizures in both patients remai ned partial until their deaths at ages 19 and 15 years, respectively. Ictal EEG verified partial onset of seizure evolving to generalized to nic-clonic seizure (GTCS). Interictal EEGs showed multifocal paroxysma l discharges with little or no diffuse paroxysms. Postmortem examinati on or genetic study confirmed the diagnosis of DRPLA. Conclusions: Sei zures of patients with DRPLA may present as partial seizures in childr en with early-onset PME.