Febrile seizures—Diagnostics and management

Abstract

Although not a type of epilepsy, febrile seizures (FS) are the most common pediatric seizure disorder, affecting 2–5% of all infants and children. According to the International League against Epilepsy (ILAE) definition proposal, FS occur in neurologically healthy children between 6 and 60 months of age, associated with fever (> 38 °C body temperature) but without evidence of central nervous system infection, a defined cause or a history of prior afebrile seizures. Subcategories include simple FS (70–90% of all FS), complex FS (10–35% of all FS) and febrile status epilepticus (FSE). The pathophysiology of FS is unclear, a multifactorial (poly)genetic and environmental etiology seems most probable. The long-term prognosis of FS is generally favorable (spontaneous remission rate 95%), although an increased risk for comorbid neuropsychiatric disorders has recently been reported. The risk for subsequent epilepsy depends on FS subcategory but does not substantially differ from that observed in the general population. However, there are conditions similar to FS at the onset but associated with an increased risk of subsequent epilepsy and neurological long-term sequelae: febrile infection related epilepsy syndrome (FIRES), hemiconvulsion-hemiplegia epilepsy (HHE) syndrome and genetic/generalized epilepsy with febrile seizures plus (GEFS+). Preclinical as well as clinical data no longer support the hypothesis of a causal role of complex FS or FSE for subsequent hippocampal sclerosis (HS) and pharmacoresistant mesial temporal epilepsy (mTLE) but suggest a pre-existing hippocampal pathology. Based on previously published evidence this update addresses recommendations for the (differential) diagnostic work-up and management of FS.