A Simple Febrile Seizure

DEFINITION

A simple febrile seizure is defined as a brief (<15 minutes) generalized seizure that occurs only once during a 24-hour period in a febrile child who does not have an intracranial infection or severe metabolic disturbance. This practice parameter is not intended for patients who have had complex febrile seizures (prolonged, ie, >15 minutes, focal, or recurrent in 24 hours), nor does it pertain to children with previous neurologic insults, known central nervous system abnormalities, or a history of afebrile seizures.

The risk of having recurrent simple febrile seizures varies, depending on age. Children younger than 12 months at the time of their first simple febrile seizure have approximately a 50% probability of having recurrent febrile seizures. Children older than 12 months at the time of their first event have approximately a 30% probability of a second febrile seizure; of those that do have a second febrile seizure, 50% have a chance of having at least 1 additional recurrence.

Children with simple febrile seizures have only a slightly greater risk for developing epilepsy by the age of 7 years than the 1% risk of the general population.

Children who have had multiple simple febrile seizures and are younger than 12 months at the time of the first febrile seizure are at the highest risk, but, even in this group, generalized afebrile seizures develop by age 25 in only 2.4%.4 No study has demonstrated that treatment for simple febrile seizures can prevent the later development of epilepsy. Furthermore, there is no evidence that simple febrile seizures cause structural damage and no evidence that children with simple febrile seizures are at risk for cognitive decline.

Despite the frequency of febrile seizures (approximately 3%), there is no unanimity of opinion about therapeutic interventions.3 The following recommendations are based on an analysis of the risks and benefits of continuous or intermittent therapy in children with simple febrile seizures. The recommendations reflect an awareness of the very low risk that a simple febrile seizure poses to the individual child and the large number of children who have this type of seizure at some time in early life. 13-5 To be commensurate, a proposed therapy would need to be exceedingly low in risks and adverse effects, inexpensive, and highly effective.

The expected outcomes of this practice parameter include the following:

1. Optimize practitioner understanding of the scientific basis for using or avoiding various proposed treatments for children with simple febrile seizures.
2. Improve the health of children with simple febrile seizures by avoiding therapies with high potential for side effects and no demonstrated ability to improve children's eventual outcomes.
3. Reduce costs by avoiding therapies that will not demonstrably improve children's long-term outcomes.
4. Help the practitioner educate caregivers about the low risks associated with simple febrile seizures.