Poster Presentation Lancefield International Symposium for Streptococci and Streptococcal Diseases 2025

Comparison of antibiotic resistance patterns of S. pneumoniae in cases of invasive pneumococcal disease and paired nasopharyngeal colonization isolates. (#218)

Morr cham 1 , Grant Mackenzie 2 , Isaac Osei 2 , Baleng Mahama Wutor 2 , Yusuf Abdulsalam 2 , Hendry Hendry Badji 2 , Rasheed Rasheed 2 , Molfa Minteh 2 , Ousman Ousman 2
  1. Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, Banjul, The Gambia, Basse santa su, Upper River Region, Gambia
  2. Disease control and Elimination (DCE), Research Microbiology, Medical research council at london school of hygiene and tropical medicine, Basse santa su, Upper River Region, Gambia

Background

This study assessed whether nasopharyngeal isolates of Streptococcus pneumoniae from hospitalized children in rural Gambia could be used to predict the prevalence of antimicrobial resistance of strains that cause invasive pneumococcal diseases.

Method

Population-based surveillance for pneumonia, septicaemia, and meningitis was conducted among children under 5 years in a rural area of The Gambia under demographic surveillance from September 2019 to December 2023. Nasopharyngeal swabs (NPS), blood cultures, cerebrospinal fluid and lung aspirates were collected. Conventional microbiology, kirby-Bauer disc diffusion method and descriptive statistic was use to determine the isolation, antibiotic susceptibility pattern and the proportion of AMR.

Result

Of the 49 IPD cases detected with homologous NPS collected, S. pneumoniae was isolated in 45 (91.8%) NPS cultures. Of the paired IPD and NPS homologous S. pneumoniae samples, 19 (42.2%) of oxacillin, 0 (0%) of chloramphenicol, 23 (51.1%) of tetracycline, 42 (93.3%) of trimethoprim-sulfamethoxazole, 40 (88.9%) of vancomycin and 0 (0%) of ceftriaxone showed resistance in NPS samples. 23 (51.1%) of oxacillin, 2 (4.4%) of chloramphenicol, 26 (57.8%) of tetracycline, 45 (100%) of trimethoprim-sulfamethoxazole, 5 (11.1%) of vancomycin and 0 (0%) of ceftriaxone demonstrated resistance in invasive samples.

Discussion

The proportions of AMR of S. pneumoniae isolates from invasive samples and NPS were comparable. These findings demonstrate that nasopharyngeal isolates of S. pneumoniae from children with suspected pneumonia may be considered as a tool to monitor for AMR in a defined setting. This tool will enable a rational and effective use of antibiotics in the clinical management of IPD.