Current pathogen profile for bacteremia in a tertiary care pediatric emergency department in Canada

Abstract

Importance: Bacteremia in children can lead to septic shock, meningitis or death. Knowledge of common pathogens and predictors is crucial for appropriate lifesaving management. Objective: We aimed to identify pathogens and associated variables in children with bacteremia presenting to the emergency department (ED). Methods: This retrospective cohort study was conducted in a tertiary pediatric hospital in Montreal, Canada (2018-2024). The full cohort included all children with a positive blood culture drawn in the ED while this study focused on cases of true bacteremia identified through medical record evaluation by two raters. The primary outcome was pathogen distribution. Potential pathogen-associated independent variables included demographics, vaccination status, recent travel, clinical presentation, and known risk factors. The primary analysis focused on pathogen prevalence, while secondary analysis assessed associations between predictors and pathogens using Chi-squared tests. Results: Among 368 bacteremia cases (median age: 39 months), the most common pathogens were Staphylococcus aureus (25%), Escherichia coli (16%), Streptococcus pneumoniae (9.0%) and non-typhoidal Salmonella (8.7%). Overall, 175 (48%) had risk factors, including internal devices (n = 80, 22%), age less than 3 months (n = 59, 16%), or immunosuppression (n = 55, 15%). Significant associations emerged: 34% (n = 38) of Staphylococcus spp. infections involved internal devices, 62% (n = 24) of Salmonella spp. infections had recent travel, and 38% (n = 22) of E. coli infections and 69% (n = 11) of group B Streptococcus infections occurred in infants aged under 3 months. Conclusions: Our study highlights current key pathogens and associated predictors in pediatric bacteremia. Travel history, internal hardware, age, and immunosuppression are crucial for clinicians to consider in its assessment and management.