Abstract
Purpose: While the literature on infantile epilepsies with minor and major seizures is extensive,
little consideration has been given to infantile epilepsy with generalized tonic-lonic
seizures (GTCS) alone. The aim of the present study was to analyze the data of a large
group of patients and their families to obtain further insight into the clinical picture
and pathogenesis of this type of epilepsy.
Methods: The 101 children (58 boys, 43 girls) met the following inclusion criteria: onset of
the epilepsy with febrile or afebrile GTCS in the first 5 years of life, absence of
primary organic brain lesion or progressive brain disease, severe course with frequent
febrile and/or afebrile GTCS, failure of conventional anticonvulsive therapy.
Results: The epilepsy predominantly afflicts normally developed infants, boys and girls being
about equally affected. The epilepsy begins with frequent febrile or afebrile GTCS,
characteristically of long duration and often with alternating lateralization. In
half of the cases additional myoclonic or myoclonic astatic seizures and/or absences
occur. The initial GTCS phase is the same in epilepsies with and without minor seizures.
Erratic myoclonias are especially characteristic.
With advancing age, the symptomatology becomes increasingly polymorphic due to the
occurrence of additional simple and complex focal and tonic seizures. Severe impairment
of mental development soon after onset is a leading symptom. The overall death rate
was 9 %. Only 11 % of the patients had been seizure-free for at least two years at final examination.
The EEC was initially normal and subsequently exhibited diffuse 4-7/s rhythms, and
only later spikes and waves of irregular shape (87 %). Focal sharp waves occurred
transiently in 26 %. The family history and EEC of probands and relatives showed the pathogenesis to be
decisively determined by genetic factors.
Conclusion: Early infantile GTCS epilepsy represents a genetically determined (idiopathic) epileptic
encephalopathy. It overlaps with other forms of early childhood epilepsy such as severe
myoclonic epilepsy, severe type of myoclonic astatic epilepsy, as well as early childhood
absence epilepsy with GTCS.
Key words
Generalized tonic-clonic seizures - Idiopathic epilepsy - Epilepsy genetics
