Simple febrile seizures: new cut off for the duration of the crises

Background: Our study aimed to identify a new cut-off for febrile seizure (FS) with a good prognosis, thereby replacing the 15 min described in the standard definition of simple febrile seizure (SFS). Methods: Our study was a retrospective observational study (from January 2018 to December 2018) on children admitted to the Pediatric emergency room of the Santobono-Pausilipon Hospital, Naples, Italy, Pediatric Unit of Latina, Rome, Italy, and Policlinico-Vittorio-Emanuele University Hospital, Catania, Italy, for fever, which developed SFS during the hospitalization. All included patients had their seizures classified as SFS according to the international criteria for epilepsy. We assumed a duration cut-off, and we analyzed the EEG results, neurological follow-up at 12 months, and the recurrence of the febrile seizures the following year. Then, with another calculation, we identify an optimal cut-off of 6 min. Finally, we divided the population into two groups: children with seizures having a duration greater than or less than 6 min. Results: We found that the population with FS with a duration greater than 6 min presented EEG alteration at follow-up visits, neurological disorders, and a recurrence of FS during the following year. Conclusions: We suggest to introduce a new cut-off for the duration of FS that better represents the benign nature of a simple febrile event.