Aetiology

aetiology

Aetiology of the condition is thought to be mulitfactorial. A combination of genetic and environmental factors contribute to the pathogenesis.

• background prevalence risk of 1 in 30 increases to
  • 1 in 5 when one sibling is affected
  • 1 in 3 if both parents and a previous child have had febrile seizures (1)

Fever itself does not cause seizures. Release of inflammatory mediators such as cytokines is responsible for the seizure activity in the developing brain (1). Any viral or bacterial infection which causes fever can result in febrile seizures:

• viral infection -human herpesvirus 6 infection (accounts for as much as 20% of children with first febrile seizures)
• otitis media
• tonsillitis
• UTI
• gastroenteritis
• lower respiratory tract infection
• meningitis (1,2)

Several other risk factors have been identified for febrile seizures:

• developmental delay
• discharge from a neonatal unit after 28 days
• day care attendance
• a family history of febrile seizures
• certain vaccinations
  • e.g. - diphtheria and tetanus toxoids and whole-cell pertussis (DTP), measles, mumps, and rubella (MMR)
  • however past history or a family history of febrile seizures is not a contraindication for immunisation
• possibly iron and zinc deficiencies (2,3)

Reference:

• (1) Patel N et al. Febrile seizures. BMJ. 2015 ;351:h4240
• (2) Deakin K. Clinical Review – Febrile seizures. GPonline 2011
• (3) Graves RC, Oehler K, Tingle LE. Febrile seizures: risks, evaluation, and prognosis. Am Fam Physician. 2012;85(2):149-53