Typical absence epilepsy presenting prior to age of 3 years: an uncommon form of idiopathic generalized epilepsy

An attempt to allocate patients with the clinical features and electroencephalography (EEG) abnormalities of typical absence epilepsy presenting before the age of 3 years, similar to childhood and juvenile absence epilepsy (JAE) and delineate the clinical manifestations, EEG abnormalities, therapy and outcome of such an epileptic disorder by conducting a nationwide survey.

Overall, eight infants, six males and two females, abided by the inclusion criteria of typical absence epilepsy: They were born after an unremarkable pregnancy and labor presenting at the age of 12-34 months (mean: 19.6 months) with frequent absences time-linked with an EEG demonstrating generalized occasionally irregular epileptiform discharges of 3-4 Hz spike/wave and normal background activity along with an electrographic photosensitive response in one patient. Neurological examination was intact in all infants. All eight infants were initially treated with valproic acid, of whom seven immediately responded and one had increase in frequency and duration of absences completely aborted with treatment of lamotrigine. Three relapsed after termination of therapy of whom two again presented with recurrent absences and another one with generalized tonic-clonic seizures and as such these children had virtually transformed into a later form of idiopathic generalized epilepsy (IGE) during childhood. All eight patients are seizure-free, seven still on therapy; seven children within a follow-up period of 2-7 years and the most recently diagnosed infant for 6 months. Cognitive skills were found normal in all children within the low normal range in three children with short attention and concentration spans.

The data presented here delineate a very rare form of idiopathic benign generalized epilepsy presenting with typical absences before age of 3 years and a favorable outcome, similar to childhood and JAE, recognized as distinct IGE syndromes by the International League Against Epilepsy (ILAE) classification.