Cross-sectional hospital-based investigation on clinical characteristics of pediatric Group A Streptococcus isolates in a Beijing hospital from 2014 to 2023.

Abstract

Background: Group A Streptococcus (GAS) is a major bacterial pathogen associated with diverse clinical diseases. Despite its general susceptibility to β-lactam antibiotics, GAS outbreaks remain a significant global health and economic concern. In this study, we retrospectively analyzed the clinical features and antimicrobial resistance patterns of GAS infections in pediatric patients in Beijing over the past decade.

Methods: Data on all GAS infections from 2014 to 2023 were collected from the microbiology department of Beijing Children's Hospital. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disc diffusion method and interpreted according to the Clinical and Laboratory Standards Institute (CLSI) guidelines.

Results: From 2014 to 2023, a total of 1,445 strains of GAS were isolated. School-age children (6-18 years) had the highest isolation rate (77.7%) among all age groups. Among the isolates, 53.6% were from outpatients (except pediatric gynecology). The top 3 wards with the highest GAS isolation rates were the rheumatology and immunology, pulmonology and dermatology wards. Most GAS infections were superficial (95.8%). Invasive infections were primarily due to bacteremia, which accounted for 40.0% of invasive cases. The isolation rate of GAS peaked in 2017 and remained at a lower level during the SARS-CoV-2 pandemic, specifically from 2019 to 2022. GAS infections also showed seasonal variation, with the highest prevalence in winter. No GAS strains were resistant to penicillin, cephalosporins, vancomycin, or linezolid. The resistance rates to erythromycin and clindamycin were generally above 90%.

Conclusion: In the post-SARS-CoV-2 period, the isolation rate of GAS has increased. GAS infections are more common in winter and summer, so children, especially school-age children, should be cautious. Given the high resistance of GAS to erythromycin and clindamycin, clinicians should limit the use of these two drugs to avoid treatment failure.