What is a febrile (fever) seizure?
A febrile seizure – or fever related seizure – causes convulsions, or in some cases body stiffening & shaking, in young children, and is induced by a sudden spike in body temperature.
What does a febrile seizure look like?
Febrile seizures are certainly scary to witness. A child can lose consciousness, and usually becomes rigid as muscles on both sides of their body contract. They may grunt, moan, or lose control of their bladder. A child’s eyes may roll upward, their muscles may jerk rhythmically, and they may or may not respond to voices.
How common are febrile seizures?
Febrile seizures are relatively common, especially among younger children. Approximately 1 in 25 kids will experience one before the age of five. (Stevenson, 2012)
The typical febrile seizure lasts for just a few minutes, though in the heat of the moment, this is likely to seem like an eternity. Many are over in mere seconds, leaving some parents confused about what exactly they witnessed, whereas some can go on as long as 10 minutes.
What causes febrile seizures?
There’s no shortage of theories about what causes febrile seizures, but it’s still largely unknown precisely what triggers them, or why some kids seem to get them and others do not. One theory is that a fast-spiking fever is what brings them on, and that it’s the speed in which a fever rises rather than a child’s overall temperature that matters. Febrile seizures typically occur during the first 24 hours of an illness while a child’s temperature is rising.
Temperature itself can also increase the brain’s “excitability,” making it more likely that an electrical storm will flare up. Since kids’ brains tend to respond to illness with a higher temperature spike than adults, this could help explain why they get them more often. Rapid breathing may also play a role, since this can disrupt the balance of oxygen and carbon dioxide in the brain.
Doctors have recently begun focusing on what role cytokines might play in seizures. Cytokines are a type of protein released by the immune system in response to illness, and are known to increase electrical activity between neurons while also turning up our internal thermostat.
Although a high temperature seems to trigger these seizures more often, there does not seem to be any minimum temperature requirement for a febrile seizure to occur. Just like a thunderstorm, seizures are the culmination of many different factors coming together to create a storm. Everything from a child’s genetics and their unique vulnerability to the type of virus triggering the infection can play a role. Certain viruses, such as Roseola and common ear infections, seem to be more frequent culprits, and febrile seizures are far more common with viruses than bacterial infections.
Are febrile seizures dangerous?
Febrile seizures are typically harmless. Most children don’t stop breathing during a febrile seizure, but they may experience breathing irregularities, which parents often mistake for their child not breathing, since it can make their skin look pale or turn the area around their lips blue. However, these seizure-induced spells of breath holding are usually far too brief to cause serious concern.
The most concerning part of a febrile seizure isn’t the seizure itself, but the temperature that often triggers it. In order to cause brain damage, a fever would have to be upward of 107 degrees Fahrenheit, and regardless, a seizure doesn’t signal that brain damage is occurring. Nonetheless, if they are caused by sudden temperature spikes, you’ll want to find out what’s causing that temperature and monitor them closely to ensure it doesn’t get too high.
Your child is likely to seem exhausted and disoriented afterwards. The disorientation is likely to subside within half an hour, but the exhaustion can linger well into the next day.
Quick facts & Statistics about febrile seizures:
1. About 4% of children ages 6 months to 5 years will experience a fever-related seizure, according to pediatrician Randy Bergen, an infectious-disease specialist at Kaiser Permanente.