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Streptococcus pyogenes infection — Clinical Guidelines

Overview

Streptococcus pyogenes, also known as group A Streptococcus (GAS), causes a range of infections from mild pharyngitis to severe invasive diseases such as necrotizing fasciitis and toxic shock syndrome. 1 6

Diagnosis

Clinical Presentation: Symptoms vary from localized infections (pharyngitis, skin infections) to systemic manifestations (sepsis, organ dysfunction). 1 6 7

Laboratory Tests: Culture remains the gold standard but can be limited by antibiotic treatment. 6

Immunohistochemical and Molecular Assays: Useful for diagnosing GAS infections in formalin-fixed, paraffin-embedded tissue samples when cultures are unavailable. 6

Biomarkers: Elevated plasma calprotectin and other inflammatory markers (CXCL10, IL-6, IL-10, IL-17A) correlate with severe disease in pediatric patients. 1

Management

Antibiotics: Penicillin G is the first-line treatment; alternatives include vancomycin or clindamycin for penicillin-allergic patients. 7

Intravenous Immunoglobulin (IVIG): Considered in severe cases, with 56% of ICU patients receiving IVIG in one study. 7

Supportive Care: Includes mechanical ventilation, renal replacement therapy, and management of organ dysfunction (renal, hepatic, coagulation, ARDS). 7

Prophylaxis: Mass prophylaxis recommended during outbreaks, especially in high-risk settings like residential aged care facilities. 2

Special Populations

Pediatrics: Severe cases may require PICU admission; biomarkers like calprotectin can predict severity. 1

Elderly: Increased vulnerability to invasive GAS infections; strict infection control measures and mass prophylaxis advised during outbreaks. 2

Immunocompetent Individuals: Recurrent invasive GAS infections can occur with different strains, necessitating close monitoring and immunological assessment. 5

Key Recommendations

Use immunohistochemical and molecular assays for diagnosing GAS infections when cultures are not feasible or delayed by antibiotic treatment. (Evidence: Moderate) 6

Implement mass prophylaxis in outbreak settings, particularly in residential care facilities, alongside stringent infection control practices. (Evidence: Expert opinion) 2

Consider IVIG in critically ill patients with invasive GAS infections given the high mortality rate and frequent need for intensive supportive care. (Evidence: Moderate) 7

Screen for and manage group B streptococcal (GBS) carriage antenatally, emphasizing the importance of recommended screening methods and antibiotic protocols, despite existing knowledge gaps among healthcare providers. (Evidence: Moderate) 4 8 10

References

1 Avendaño-Ortiz J, Aguilera-Alonso D, Rodríguez CM, Oteo-Iglesias J, Lozano-Rodríguez R, López-Collazo E et al.. Plasma calprotectin as a severity biomarker in pediatric invasive Streptococcus pyogenes infections: insights from a multicenter immune profiling study during an outbreak. Journal of microbiology, immunology, and infection = Wei mian yu gan ran za zhi 2026. link 2 Vasant BR, Jarvinen KAJ, Fang NX, Smith HV, Jennison AV. Mass prophylaxis in an outbreak of invasive group A streptococcal disease in a residential aged care facility. Communicable diseases intelligence (2018) 2019. link 3 Soderholm AT, Walker MJ. A Host Proteome Atlas of Streptococcus pyogenes Infection. Cell systems 2018. link 4 Price CA, Green-Thompson L, Mammen VG, Madhi SA, Lala SG, Dangor Z. Knowledge gaps among South African healthcare providers regarding the prevention of neonatal group B streptococcal disease. PloS one 2018. link 5 Gazzaz N, Mailman T, Foster JR. Recurrent invasive group A streptococcal infection with four-limb amputation in an immunocompetent child. BMJ case reports 2018. link 6 Guarner J, Sumner J, Paddock CD, Shieh WJ, Greer PW, Reagan S et al.. Diagnosis of invasive group a streptococcal infections by using immunohistochemical and molecular assays. American journal of clinical pathology 2006. link 7 Mehta S, McGeer A, Low DE, Hallett D, Bowman DJ, Grossman SL et al.. Morbidity and mortality of patients with invasive group A streptococcal infections admitted to the ICU. Chest 2006. link 8 Morin CA, White K, Schuchat A, Danila RN, Lynfield R. Perinatal group B streptococcal disease prevention, Minnesota. Emerging infectious diseases 2005. link 9 Watt JP, Schuchat A, Erickson K, Honig JE, Gibbs R, Schulkin J. Group B streptococcal disease prevention practices of obstetrician-gynecologists. Obstetrics and gynecology 2001. link01401-6) 10 Jafari HS, Schuchat A, Hilsdon R, Whitney CG, Toomey KE, Wenger JD. Barriers to prevention of perinatal group B streptococcal disease. The Pediatric infectious disease journal 1995. link

Streptococcus pyogenes infection