Epileptic spasms in older children: persistence beyond infancy.

Although infantile spasms (IS) constitute a well-recognized epileptic syndrome, only recently did investigators propose that spasms be classified as a distinct seizure type, characterized by axial flexion/extension jerks in clusters. Five older children (aged 4.5-14.2 years) who underwent video-EEG monitoring in 1992 in our epilepsy program for intractable mixed seizure disorder (cryptogenic 1, symptomatic 4) demonstrated flexor and extensor spasms in clusters. Seizure onset was from birth to 1.33 years. All 5 had spasms during infancy that continued as the children aged. Ictal EEG during spasms showed a brief high-amplitude delta burst followed by diffuse background attenuation or diffuse background decrease with superimposed rhythmic beta or alpha activity. Multiple other seizure types were present. Interictal EEGs were markedly abnormal and demonstrated slowing, multifocal spikes, generalized slow spike-wave, and polyspike-wave. Two children with spasms were unsuccessfully treated with ACTH, and 3 underwent corpus callosotomy. We conclude that spasms occur in older children with intractable mixed seizure disorders and may persist beyond infancy.