From the Guidelines
Febrile seizures are categorized as simple or complex based on specific characteristics, and the prognosis and recommended work-up differ significantly between the two types, with simple febrile seizures having an excellent prognosis and requiring minimal work-up, as stated in the most recent guidelines 1. The key characteristics of simple febrile seizures include duration of less than 15 minutes, generalized (not focal) seizures, occurrence once in a 24-hour period, and spontaneous resolution.
- Simple febrile seizures have an excellent prognosis, with no increased risk of epilepsy beyond the general population (1-2%) and no impact on cognitive development, as supported by the American Academy of Pediatrics practice parameter 1.
- Complex febrile seizures, on the other hand, carry a slightly higher risk of developing epilepsy (4-15%), particularly if multiple risk factors are present, and require a more thorough evaluation, including consideration of lumbar puncture in children under 12 months or with signs of meningitis, as recommended by the American College of Radiology 1. For simple febrile seizures in children 6 months to 5 years with normal neurological examination and no concerning history,
- minimal work-up is needed beyond identifying and treating the fever source, as stated in the guidelines 1.
- Laboratory tests are not routinely recommended unless needed to identify the fever source, and antipyretics may be used for comfort, but will not prevent subsequent seizures, as demonstrated by recent meta-analyses 1. For complex febrile seizures,
- a more thorough evaluation is warranted, including consideration of lumbar puncture in children under 12 months or with signs of meningitis, and EEG may be considered for complex cases, as recommended by the American College of Radiology 1.
- Neuroimaging (CT/MRI) is generally unnecessary for typical febrile seizures but may be indicated for focal seizures, abnormal neurological findings, or signs of increased intracranial pressure, as stated in the guidelines 1. The primary management focuses on parent education, antipyretic use for comfort, and reassurance about the benign nature of most febrile seizures, as supported by the American Academy of Pediatrics practice parameter 1 and the American Heart Association guidelines 1.
From the Research
Febrile Seizure Classification
- Simple febrile seizures are characterized by a short duration, typically less than 15 minutes, and do not recur within 24 hours 2.
- Complex febrile seizures last 15 minutes or more, are associated with focal neurologic findings, or recur within 24 hours 2.
Prognosis
- Febrile seizures are generally benign and self-limiting, with a favorable prognosis 2, 3.
- Children with febrile seizures are at risk of recurrence, with approximately 30-40% experiencing a recurrence during early childhood 3.
- Complex febrile seizures are associated with an increased risk of subsequent epilepsy 3.
Recommended Work-up
- Routine diagnostic testing, including laboratory tests, neuroimaging, and electroencephalography, is not recommended for simple febrile seizures unless indicated by the patient's condition or medical history 4, 5, 2.
- For complex febrile seizures, the neurologic examination should guide further evaluation 2.
- A lumbar puncture should be considered in children younger than 12 months of age or with suspected meningitis 3.
- Most patients with complex febrile seizures do not require extensive diagnostic workup, with a low yield of positive results from diagnostic studies 6.