Related Experiment Video
Updated: Sep 11, 2025

Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria
Published on: February 23, 2014
Evolving treatment strategies for invasive Streptococcus pyogenes in children in the postpandemic era
Laura Buricchi1, Giuseppe Indolfi2,3, Marco Renni1,4
1Department of Health Science, University of Florence, Florence, Italy.
Insights
Invasive Group A Streptococcus (iGAS) infections in children increased post-pandemic, with pneumonia as a common presentation. Linezolid shows promise as a second-line therapy for treatment failures, while IVIG use requires further study.
Area of Science:
- Pediatric Infectious Diseases
- Bacteriology
- Clinical Microbiology
Background:
- Group A Streptococcus (GAS) causes pharyngitis and skin infections, with invasive GAS (iGAS) infections posing severe risks in children.
- The COVID-19 pandemic correlated with increased iGAS cases, influenced by factors like age, waning immunity, and viral coinfections.
- Standard iGAS treatments (clindamycin, IVIG) lack standardization in pediatrics; linezolid is emerging as a potential alternative.
Purpose of the Study:
- To assess iGAS treatment effectiveness in hospitalized children.
- To evaluate alternative interventions like linezolid for treatment failures or severe infections.
- To identify risk factors for pediatric intensive care unit (PICU) admission in iGAS cases.
Main Methods:
- Retrospective observational study of children (<18 years) with iGAS from September 2022 to September 2024.
- Collected data included demographics, symptoms, lab results, microbiology, coinfections, therapies, and outcomes.
- Focus on treatment strategies, including standard and alternative antibiotic/non-antibiotic interventions.
Main Results:
- Forty-six children with iGAS were included; 16 required PICU admission, and 2 died.
- Pneumonia with parapneumonic abscess/empyema was the most frequent presentation.
- Linezolid was used in 5 cases (10.9%) after beta-lactam and clindamycin failure; elevated CRP/procalcitonin predicted PICU admission.
Conclusions:
- iGAS treatment and disease patterns have evolved post-pandemic, with pneumonia being a key presentation.
- Linezolid is a viable second-line option following beta-lactam and clindamycin failure in pediatric iGAS.
- Intravenous immunoglobulin (IVIG) use in severe iGAS cases was often delayed, necessitating further research on optimal timing and efficacy.
Background:
Streptococcus pyogenes (group A Streptococcus [GAS]) is a common cause of bacterial pharyngitis and skin infections in children that can lead to severe and invasive GAS (iGAS) infections. The sudden acute respiratory syndrome coronavirus 2 pandemic coincided with an increase in iGAS cases, with emerging serotypes and risk factors like age, reduced postpandemic immunity, and viral coinfections. The treatment of iGAS with clindamycin and intravenous immunoglobulins (IVIG) is not well standardized, and pediatric data are limited. Linezolid is being explored as an alternative to clindamycin, although further research is required.
Purpose:
This study aimed to evaluate the treatment of iGAS in hospitalized children with focus on the effectiveness of standard treatments and the role of alternative interventions in cases of treatment failure, including the use of linezolid or severe infections. Additionally, this study sought to identify the potential risk factors for pediatric intensive care unit (PICU) admission.
Methods:
A retrospective observational study was conducted in children aged <18 years admitted to Meyer University Children's Hospital (September 2022 to September 2024) with confirmed or probable iGAS. Their anonymized general information, symptoms, laboratory test results, microbiological test results, coinfections, radiological examination results, antibiotic and nonantibiotic therapies, discharge information, and outcomes were collected.
Results:
Forty-six children with confirmed/probable iGAS (median age, 53.7 months) were included. Of them, 34 (73.9%) had confirmed iGAS and 12 (26.1%) had probable iGAS. Sixteen children (34.8%) with iGAS were admitted to the PICU; of them, 2 died. All children received beta-lactam antibiotics; in 5 cases (10.9%), linezolid was administered after beta-lactam and clindamycin therapy failure. Thirty patients (65.2%) underwent surgery. Of the study population, 22% had preexisting conditions and 17% had viral respiratory coinfections. Elevated C-reactive protein and procalcitonin levels were independent risk factors for PICU admission. IVIG administered to 3 patients had varying outcomes.
Conclusion:
Our findings highlight how treatment strategies and disease patterns have shifted in the postpandemic period. Pneumonia with a parapneumonic abscess or empyema has emerged as the most frequent clinical presentation, with nearly half of such cases requiring second-line linezolid therapy. Linezolid may be a valuable treatment alternative after beta-lactam and clindamycin failure. IVIG has been used in severe cases but often late, warranting further investigation into its optimal application.
Related Concept Videos
Acute Pyelonephritis II: Diagnostic Studies and Management
Tonsillitis II: Management
Endocarditis III: Medical Management
Pneumonia IV: Management
Bacterial Pneumonia Treatment
For bacterial pneumonia, antibiotics serve as the cornerstone of therapy. Initial treatment often begins with empirical antibiotics, tailored to the anticipated causative organism and adjusted based on culture results. Key antibiotic choices include:
Acute Pyelonephritis I: Introduction
Acute Pharyngitis
Acute pharyngitis is the inflammation of the back of the throat (pharynx), commonly resulting in a sore throat. It is a frequently encountered condition that prompts individuals to seek medical advice.
Classification
Acute pharyngitis can be categorized based on its underlying cause:

