G339(P) Is blood culture a useful investigation in children admitted to hospital with community-acquired pneumonia?

Abstract

Aims Several papers in recent years have challenged the utility of blood cultures in children presenting with community acquired pneumonia. We aim to determine the usefulness of blood cultures taken at the time of initial presentation in the subsequent management of children with lower respiratory tract infections in our institution. Methods From a database of all blood cultures taken in the Paediatric Emergency Department (PED) and Children’s Assessment Unit (CAU), we identified a cohort of children who had been admitted to hospital and discharged with a diagnosis of lower respiratory tract infections who had undergone a blood culture test at the time of initial assessment. We retrospectively reviewed the blood culture results, respiratory microbiology (if obtained) and discharge letters of all children (aged 0–16) who had blood cultures sent in January and May 2016 from ED or CAU and were subsequently discharged with ‘lower respiratory tract infection’ as their main diagnosis. Results 105 patients were identified. The dataset was complete as all records were available via the hospital ICE system. Of 105 blood cultures, 2 were positive (1.9%). One was positive for Streptococcus pneumonia and the other for Coagulase Negative Staphylococcus. The latter was concluded to be a contaminant of no clinical significance. As such only 1/105 was a true positive (0.95%) and was fully sensitive to empirical therapy per our hospital antibiotic policy. 34/105 (32.3%) had positive respiratory virology, predominantly from nasopharyngeal aspirate. 34/105 (32.3%) were discharged less than 48 hours from the time of the blood culture. Only two discharge letters specifically made reference to ‘sepsis’ as part of the diagnosis. Conclusion Recent evidence to suggest the lack of clinical utility of blood cultures is supported by our local data. Indeed, approximately a third of our patients were discharged before the result of their blood culture was even known. The practice of sending blood cultures for these patients may be borne out of pragmatism around blood-taking from young children; however it is increasingly evident that they add little to clinical management in children with pneumonia.