Febrile seizures: is the EEG a useful predictor of recurrences?

We examined the predictive value of a paroxysmal EEG in children with febrile seizures seen at the University Pediatric Clinic, Skopje, Macedonia, between 1982 and 1984. This was the only facility providing EEG or neurologic consultation for children in Macedonia, and almost all children in the area who experienced a febrile seizure were referred to this facility. EEGs were classified as epileptiform if they contained spikes and sharp waves or spike wave complexes, which were either focal or generalized, and were considered abnormal for age and state. Nonspecifically abnormal was defined as focal or generalized slowing excessive for age and state. Follow-up visits were scheduled at 6-month intervals; mean follow-up time was approximately 23 months. In order to determine whether clearly abnormal EEG features would predict recurrences, we compared the recurrences in 170 children with initial normal-appearing EEGs with 99 children with initial paroxysmal EEGs. There was no significant difference in risk of recurrence of febrile seizures between the two groups; increase in recurrence risk was determined primarily by younger age. The EEG did not add information regarding the likelihood of recurrence of febrile seizures.