Evaluation of the WHO clinical decision rule for streptococcal pharyngitis

A W Rimoin1, H S Hamza, A Vince

  • 1Department of Epidemiology, School of Public Health, University of California, Los Angeles, CA, USA. arimoin@ucla.edu

Insights

The World Health Organization clinical decision rule (CDR) for group A beta haemolytic streptococcal (GABHS) pharyngitis shows high specificity but low sensitivity in identifying GABHS infections in children across three countries.

Area of Science:

  • Pediatric infectious diseases
  • Clinical diagnostics
  • Public health

Background:

  • Group A beta-hemolytic streptococcal (GABHS) pharyngitis is a common childhood illness.
  • Accurate diagnosis of GABHS pharyngitis is crucial to prevent complications like rheumatic fever.
  • The World Health Organization (WHO) developed a clinical decision rule (CDR) to aid diagnosis.

Purpose of the Study:

  • To prospectively evaluate the diagnostic accuracy of the WHO CDR for GABHS pharyngitis.
  • To assess the performance of the WHO CDR across different international settings.

Main Methods:

  • Prospective, observational cohort study involving 2225 children aged 2-12 years in Brazil, Egypt, and Croatia.
  • 1810 children with sore throat were analyzed for GABHS pharyngitis.
  • WHO CDR performance was assessed for sensitivity and specificity.

Main Results:

  • GABHS pharyngitis prevalence varied from 24.6% to 42.0% across study sites.
  • The WHO CDR demonstrated high specificity (93.8-97.4%) but low sensitivity (0.0-10.8%) in all age groups and countries.
  • The rule failed to identify a significant proportion of children with confirmed GABHS pharyngitis.

Conclusions:

  • The current WHO CDR is not sufficiently sensitive for diagnosing GABHS pharyngitis in these populations.
  • A revised CDR with improved sensitivity is needed, especially in regions with high burdens of rheumatic fever and rheumatic heart disease.
  • Further research should focus on developing more sensitive diagnostic tools for GABHS infections.
Abstract

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