Overview
Clinical Meaning
A febrile seizure is a seizure occurring in a child 6 months to 5 years of age with a temperature of at least 38 °C (100.4 °F), when a central nervous system infection is not ca...
A febrile seizure is a seizure occurring in a child 6 months to 5 years of age with a temperature of at least 38 °C (100.4 °F), when a central nervous system infection is not causing the seizure. A seizure with fever in an infant younger than 6 months or a child older than 5 years does not fit this definition and requires evaluation for another cause. The developing brain has a lower seizure threshold because excitatory signalling is relatively strong compared with inhibitory control. Fever and the inflammatory mediators released during infection can further increase neuronal excitability, allowing a brief, provoked seizure. This mechanism explains why a febrile seizure is not, by itself, epilepsy; the clinician must still exclude meningitis, encephalitis, metabolic disturbance, intoxication, and an unprovoked seizure. | Simple febrile seizure | Complex febrile seizure | | --- | --- | | Generalized movements | Focal onset or focal features | | Less than 15 minutes | Lasts 15 minutes or longer | | One seizure in a 24-hour period | More than one seizure in 24 hours...