The clinical and EEG family data of 140 cases of early childhood epilepsy with absences selected from the epilepsy family archive are reported from the Neuropaediatric Department of the University of Kiel, Germany. Patients with absences manifesting between the 1st and 5 th year of age were selected for study. Two groups were formed: 1) GTCS, those presenting with generalized tonic-clonic seizures (90 cases); and 2) non-GTCS, presenting with absences (50 cases). GTCS at onset were afebrile or febrile. In 43% of probands absence were combined with myoclonic and/or myoclonic astatic seizures. Parents and their sibs of group 1 had seizures twice as often as parents and sibs in group 2. The EEG of relatives showed elevated incidences of spike and wave and photosensitivity in both groups. However, in parents of the non-GTCS group, EEG abnormality was more frequent than in parents of the GTCS group. Mothers’ EEG was the best predictor of seizure risk in probands’ siblings. Early childhood epilepsy with absences overlaps with early onset GTCS and myoclonic astatic epilepsy on one hand and with childhood absence epilepsy on the other. This syndrome could not be regarded as a specific entity. The analysis supports the assumption of heterogeneity within early childhood absence epilepsy. [1]
COMMENT. Three type of absence epilepsy are distinguished by the International Classification: 1) childhood absence with absence as presenting symptom, 2) juvenile absence with or without GTCS, and 3) epilepsy with myoclonic absences. Absence epilepsy of early childhood has not been distinguished as a specific entity, although Doose has demonstrated some characteristics which might allow differentiation from childhood absence. These include: onset before 5 years of age with absences or GTCS, male preponderance, associated myoclonic and/or myoclonic astatic seizures, poor response to AEDs, and unfavorable psychologic and social development in children with GTCS. The clinical and family data reported here are considered to support genetic heterogeneity within the disorder. Both non-GTCS and GTCS forms of the syndrome appear to be part of the larger spectrum of idiopathic generalized epilepsies of childhood.