febrile seizure plus
Febrile seizures that extend beyond typical age limits or occur with low-grade fever, often indicating genetic predisposition.
Full Definition
Febrile seizure plus (FS+) refers to an extended phenotype of febrile seizures that occurs outside the typical parameters of simple febrile seizures. These may include seizures occurring beyond age 6 years, with low-grade fevers (<38°C), or in family members with a history of epilepsy. FS+ is often associated with genetic mutations, particularly in sodium channel genes (SCN1A, SCN1B), and may progress to various epilepsy syndromes including Dravet syndrome or genetic epilepsy with febrile seizures plus (GEFS+).
Usage
Usage note: Often abbreviated as FS+; distinguish from complex febrile seizures by family history and genetic implications.
In Context
- "The family history of febrile seizure plus suggested an underlying genetic syndrome." — Genetic counseling assessment
- "SCN1A testing was ordered given the phenotype of febrile seizure plus." — Molecular genetics consultation