Febrile seizure

Background

• 50% of patients never have temp >39
• Antipyretics do not offer significant improvements in recurrence rates of febrile seizures

Prognosis

• 2-3% chance of developing epilepsy (1% for general population)
• 50% of patients <12 mo will have another simple febrile seizure
• 30% of patients >12 mo will have another simple febrile seizure

Clinical Features

• Seizure + fever

Differential Diagnosis

Pediatric seizure

• Epileptic seizure
  • First-time seizure
  • Seizure with known seizure disorder
  • Status epilepticus
  • Temporal lobe epilepsy
  • Non-compliance with or "outgrowing" AEDs
• Non-epileptic seizure
  • Meningitis
  • Encephalitis
  • CNS abscess
  • Intracranial hemorrhage
  • Alcohol withdrawal
  • Benzodiazepine withdrawal
  • Metabolic abnormalities: hyponatremia, hypernatremia, hypocalcemia, hypomagnesemia, hypoglycemia, hyperglycemia
  • Pyridoxine responsive seizure
  • Eclampsia
  • Neurocysticercosis
  • Posterior reversible encephalopathy syndrome
  • Impact seizure (head trauma)
  • Seizure with VP shunt
  • Toxic ingestion
  • Psychogenic nonepileptic seizure (pseudoseizure)
• Hydrocephalus
• Intracranial mass
• Syncope
• Breath-holding spell
• Hyperventilation syndrome
• Migraine headache
• Movement disorders
• Narcolepsy/cataplexy
• Post-hypoxic myoclonus (Status myoclonicus)
• Infatile Spasms/West Syndrome

Pediatric fever

• Upper respiratory infection (URI)
• UTI
• Sepsis
• Meningitis
• Febrile seizure
• Pneumonia
• Acute otitis media
• Whooping cough
• Unclear source
• Kawasaki disease
• Neonatal HSV
• Specific virus
  • COVID-19 (peds)

Diagnosis

Simple versus Complex

• Simple
  • Generalized tonic-clonic seizure
  • <15 min in duration
  • Age 6mo - 5yr
  • Occurs only once in 24hr period
  • No focal features
• Complex
  • Any exception to above

Work-Up

• Glucose in all patients

Simple febrile seizure

• Neither labs nor neuroimaging are absolutely necessary
• Normal pediatric fever workup

Complex febrile seizure

• Consider CBC, blood culture, UA, urine culture, CSF studies
• Consider CT if:
  • Persistently abnormal neuro exam (especially with focality)
  • Signs/symptoms of increased ICP
  • Patient has VP shunt
• Consider ECG if:
  • Family history of long QT, Brugada, sudden death
• Routine EEG not indicated
  • Consider only if developmental delay or for focal symptoms
• Causes amenable to specific treatment
  • Hypoglycemia
  • Hyponatremia (water intoxication, dilution of formula)
  • Hypocalcemia
  • Hypomagnesemia
  • INH ingestion

Management

Ongoing Seizure

See Seizure (peds)

Seizure Stopped

• Treat underlying infection if indicated
  • See pediatric fever of uncertain source

Disposition

Discharge

• Simple febrile seizure if patient at baseline
  • Follow-up in 1-2d
• Complex febrile seizure if patient well-appearing, work-up normal
  • Follow-up in 24hr

Admit

• Ill-appearing
• Lethargy beyond postictal period

See Also

• Seizure
• Fever (Peds)