Causes
The direct cause of a febrile seizure is not known; however, it is normally precipitated by a recent upper respiratory infection or gastroenteritis. A febrile seizure is the effect of a sudden rise in temperature (>39°C/102°F) rather than a fever that has been present for a prolonged length of time. Parents caring for children that may be febrile who wrap them up in warm blankets in an attempt to give comfort unknowingly increase their fever and therefore the risk.
Febrile seizures occurring in children between the ages of 6 months and about 6 years can be due to a hypersensitive hypothalamus in the brain. The hypothalamus is responsible for homeostatic core temperature regulation, (amongst other factors) and in younger children it is still a developing portion of the brain, meaning it is susceptible to hypersensitive reactions to slight raises in body temperature.
Febrile seizures represent the meeting point between a low seizure threshold (genetically and age-determined; some children have a greater tendency to have seizures under certain circumstances) and a trigger, which is fever. The genetic causes of febrile seizures are still being researched. Some mutations that cause a neuronal hyperexcitability (and could be responsible for febrile seizures) have already been discovered.
Several genetic associations have been identified. These include:
Type | OMIM | Gene |
---|---|---|
FEB3A | 604403 | SCN1A |
FEB3B | 604403 | SCN9A |
FEB4 | 604352 | GPR98 |
FEB8 | 611277 | GABRG2 |
Certain forms are considered channelopathies.
Read more about this topic: Febrile Seizure