Benign partial epilepsy in infancy long-term outcome and marginal syndromes.

Benign partial epilepsy in infancy (BPEI) is an infantile epilepsy with excellent seizure and developmental outcome proposed by Watanabe et al. Our telephone interview survey revealed that the long-term outcome of patients with BPEI was also excellent over 8 years of age. Six of 39 patients did not fulfill the criteria of BPEI by the last follow-up. Two patients had a recurrence of unprovoked seizure beyond 2 years of age, three had cognitive problems (mild mental retardation in two and Asperger syndrome in one) and the other had both a recurrence of seizure and mild mental retardation. These results indicates that a large majority of patients diagnosed as possible BPEI at 2 years of age did not have a recurrence of unprovoked seizures and mental problems beyond 8 years of age. Our study also suggested a presence of some marginal syndromes of BPEI. An association of paroxysmal kinesigenic choreoathetosis was observed in three patients. Another three patients had experienced seizures with mild gastroenteritis. The seizure outcome of three patients with mild cognitive problems was quite excellent. These patients can be grouped as a marginal syndrome of BPEI.