Dear Dr. Theriot:
My granddaughter is 2 years old and she had a febrile seizure when I was baby-sitting her. The paramedics took her to the emergency room. The doctor said that she would be just fine--that the seizure was due to the fever. He told me to watch her fevers very closely in the future, that it could happen again. It scared my husband and I half to death. We're afraid to watch her anymore. Could you tell us a little more about "febrile seizures?"
I can sympathize with you and your husband. A convulsion can be a terribly frightening thing to witness...it leaves you feeling so helpless. Febrile seizures occur in 2-4% of all children in the U.S. They occur between three months and five years of age, and are slightly more common in males. They are not felt to be indicative of a child having epilepsy, as fewer than 5% of children who have had a febrile convulsion actually do develop epilepsy.
Febrile seizures usually occur early on in the course of an illness, and some feel that they occur when the fever is on the rise (although this has not been shown conclusively). Most of them are associated with common infections such as ear infections, tonsillitis, or viral illnesses.
The seizure typically is as follows: there may be a loud cry, loss of consciousness and the eyes may roll up in the head. The patient then becomes rigid and stiff (tonic). Then there is a rhythmic, jerky movement of all four extremities (clonic) that can last from seconds to minutes after which the patient goes limp (post-ictal). After the seizure, the patient may sleep or seem dazed and lethargic for a brief period before returning to their normal state. Most febrile seizures are of this tonic-clonic type.
Complex febrile seizures are prolonged (longer than 15 minutes), tend to be multiple in a 24-hour period, or are focal--involving only one part of the body.
Approximately one-third of children who have febrile convulsions will have a second one at some point in time. About 9% will go on to have three or more. Most recurrences however (over 75%), will occur within one year.
Family history is important in assessing a child with febrile seizures. Siblings are at a 10-20% risk of having febrile seizures themselves---it is higher if the parents have had febrile seizures when they were young.
Recent studies have shown that predictors of recurrent febrile seizures include: 1) young age at onset 2) short duration of fever before the seizure 3) relatively low degree of fever by the time medical personnel evaluate the child and 4) history of febrile seizures in a first degree relative.
Simple febrile seizures are benign conditions although terribly frightening for family members to observe. Most children do very well, and studies have shown that there is no impact on motor or intellectual development as they grow up. The only real treatment is reassurance and educating the family about febrile seizures. Communication is critical in trying to allay any fears. Only in very special circumstances are anti-convulsant medications used.
Complex febrile seizures are a bit more complicated, and they often times do require more of a "work-up" with special tests. In many cases of complex febrile seizures, the input of a specialist is sought to guide in the work-up and management of these patients.