Bacterial detection in paediatric cancer patients with febrile neutropenia, from conventional microbiological testing to advanced molecular techniques: a scoping review

Introduction Febrile neutropenia (FN) is a common complication of cancer treatment and carries a risk of bacterial bloodstream infection. Current diagnostic approaches have limitations, underscoring the need for improved methods. This review maps evidence on diagnostics for bacteraemia in paediatric FN, focusing on peripheral blood cultures (BCs) in children with central venous catheters, repeat BC strategies and emerging molecular diagnostics and biomarkers. Methods A scoping review was conducted in accordance with Joanna Briggs Institute methodology and reported using the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) checklist. MEDLINE, Embase and Web of Science were searched for primary research published since 2011 evaluating diagnostic techniques for bacteraemia in children with cancer and FN. Study selection was performed independently by two reviewers. Data on study characteristics, diagnostic methods and performance were extracted. Results Of 1641 records, 33 studies (8993 FN episodes) were included: biomarker assays (n=20), BC (n=7) and molecular diagnostics (n=6). Evidence for routine peripheral BC was limited and conflicting. A temporal decline in BC diagnostic yield was observed, associated with increasing contamination. Molecular diagnostics consistently detected more pathogens than conventional culture, although evidence of clinical benefit remains limited. No biomarker demonstrated sufficient accuracy for standalone use. Methodological heterogeneity limited comparative analysis. Conclusion BCs remain the diagnostic gold standard for bacteraemia in paediatric FN. Repeated BCs beyond 72 hours are unlikely to benefit clinically stable patients. Molecular diagnostics and biomarkers are promising adjuncts but require further evaluation through standardised prospective multicentre studies. Integrating pathogen detection with host response biomarkers should be considered to improve diagnostic accuracy.