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Evaluating fever of unidentifiable source in young children

Denise K Sur1, Elise L Bukont

  • 1David Geffen School of Medicine, University of California, Los Angeles, 90404, USA. dsur@mednet.ucla.edu

American Family Physician
|July 11, 2007
PubMed

Insights

Fever in young children often has a viral cause. Vaccinations have reduced serious bacterial infections, allowing for fewer tests and less presumptive treatment in well-appearing febrile children.

Area of Science:

  • Pediatrics
  • Infectious Diseases
  • Vaccinology

Background:

  • Febrile illnesses are common in children under 36 months.
  • Occult bacteremia and serious bacterial infections were previously found in ~10% of febrile children without a clear source.
  • Recent vaccination advancements have significantly lowered bacterial infection rates.

Purpose of the Study:

  • To review current recommendations for evaluating febrile children.
  • To discuss the impact of vaccines on the diagnosis and treatment of febrile illnesses.
  • To highlight evolving approaches to managing fever in young children.

Main Methods:

  • Literature review of studies on febrile illness in children.
  • Analysis of infection rates before and after widespread vaccine use.
  • Examination of current clinical guidelines for sepsis work-up and management.

Main Results:

  • Recent studies show bacterial infection rates of 1.6-1.8% in febrile children.
  • Vaccinations against Haemophilus influenzae type b and Streptococcus pneumoniae have decreased infection rates.
  • Recommendations are shifting towards fewer tests and less empiric treatment for well-appearing, vaccinated children.

Conclusions:

  • Evaluation and treatment strategies for febrile children are evolving due to vaccination.
  • Nontoxic, vaccinated children aged 1-36 months with fever may undergo screening and close follow-up.
  • A cautious approach remains essential due to the risks of untreated serious bacterial infections.

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