Dr Kola Tytler MBBS CertHE MBA MRCGPClinical Lead • iatroX
For diagnosing Group A Streptococcal (GAS) infections in children presenting with a sore throat, clinical assessment alone is considered unreliable, necessitating laboratory confirmation Shulman et al. 2012Curatola et al. 2024.
Initial Assessment:
- Clinical scoring systems, such as the Centor or McIsaac scores, can be used to help identify children at a higher risk for GAS pharyngitis Shulman et al. 2012. However, these scores do not replace the need for laboratory testing Shulman et al. 2012Curatola et al. 2024.
Laboratory Confirmation:
- Rapid Antigen Detection Tests (RADTs): These are commonly used for initial diagnosis due to their high specificity, although their sensitivity can be variable Shulman et al. 2012Curatola et al. 2024.
- Confirmatory Throat Culture: In children, a negative RADT result should typically be confirmed by a throat culture Shulman et al. 2012Curatola et al. 2024. This is crucial due to the potential risk of acute rheumatic fever if GAS pharyngitis is missed Shulman et al. 2012Curatola et al. 2024. Throat culture is considered the gold standard for diagnosis Shulman et al. 2012Curatola et al. 2024.
- Molecular Tests: Newer molecular diagnostic tests, such as nucleic acid amplification tests (NAATs), offer higher sensitivity and specificity compared to traditional RADTs Cohen et al. 2024Curatola et al. 2024. These advanced tests can potentially reduce the need for confirmatory throat cultures following a negative result Cohen et al. 2024.
The overarching goal of accurate diagnosis is to prevent serious complications like acute rheumatic fever and post-streptococcal glomerulonephritis, while also promoting appropriate antimicrobial stewardship by avoiding unnecessary antibiotic prescriptions Cohen et al. 2024Curatola et al. 2024.
Key References
- CG84 - Diarrhoea and vomiting caused by gastroenteritis in under 5s: diagnosis and management
- NG237 - Suspected acute respiratory infection in over 16s: assessment at first presentation and initial management
- NG143 - Fever in under 5s: assessment and initial management
- (Shulman et al., 2012): Clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis: 2012 update by the Infectious Diseases Society of America.
- (Cohen et al., 2024): Group A Streptococcus pharyngitis in Children: New Perspectives on Rapid Diagnostic Testing and Antimicrobial Stewardship.
- (Curatola et al., 2024): Diagnosis and Treatment of Group A Streptococcal Pharyngitis in Children.