Early-onset absence epilepsy: clinical and electroencephalographic features in three children

To describe the clinical and electroencephalographic features of three infants diagnosed as having early-onset absence seizures. Two males and one female, aged 21-29 months were seen in our neuropaediatric outpatient clinic because of daily episodes of motor arrest and loss of contact. Neurological examination and mental development was considered normal in all of them. Two out three had first-degree relatives with seizures with onset in the childhood and favourable evolution in the adulthood. A video-electroencephalogram was requested. Ictal EEG revealed a normal background and generalised spike-and-wave complexes at 3-3.5 Hz accompanied by disruption of ongoing activity in keeping with absence seizures. The duration of seizures ranged from 2 to 10s. One child (patient 2) experienced rhythmic myoclonic jerks in upper limbs and head as those described in myoclonic absences. Clinical and electroencephalographic follow-up ranged from 8 months to 4 years. Two children were on treatment with valproate and in the case of the patient 3, the combination of valproate and ethosuximide was necessary. Control of absence seizures was achieved in all our cases. Absence seizures should be considered as a possible cause of transient impairment of consciousness even among infants minor than 3 years of age. A video-electroencephalogram is the method of choice in the diagnostic evaluation and syndromic classification of these paroxysmal events.