Situation and questions regarding the practice of blood cultures in paediatric patients: an opinion paper

The collection and interpretation of blood cultures in paediatric patients require specific considerations that make simple extrapolation from adult recommendations inappropriate. In recent years, the incidence and aetiology of paediatric bacteraemia have evolved, influenced by vaccination programmes, improved infection prevention strategies, and increasing clinical complexity, particularly in neonatal, oncohaematological, and intensive care settings. Clinical guidelines recommend blood cultures in neonates and infants with fever without a focus in children with sepsis or shock, with immunosuppression, suspected endovascular infection, meningitis, osteoarticular infections, or severe community-acquired pneumonia. Conversely, routine use is discouraged in clearly viral infections and in mild cases in previously healthy children. Available evidence consistently identifies the volume of blood inoculated as the main determinant of diagnostic performance, and this should be adjusted for age and weight. Obtaining one or two appropriately indicated peripheral blood culture sets, together with proper antisepsis, reduces contamination and improves clinical interpretation. Whenever feasible, both aerobic and anaerobic bottles should be included, given their complementary diagnostic yield. There is no robust evidence that paediatric bottles with smaller broth volumes provide substantial advantages over standard bottles when adequate blood volumes are inoculated. Importantly, no evidence demonstrates that the type of bottle or automated system used influences hospital stay, clinical outcomes, or mortality. This article presents an evidence-informed perspective that integrates current literature with expert clinical judgment, derived from more than four decades of experience at a high-complexity tertiary-care hospital.