Evaluating the Proportion of Low-Value Blood Cultures Obtained in a Pediatric Emergency Department

Existing literature suggests that for some pediatric conditions, blood cultures may be of low value in specific clinical circumstances. The goals of our study were to: 1) identify common pediatric illnesses and define criteria for low-value blood cultures in children aged from 91 days to 19 years, 2) apply these criteria retrospectively to identify the patients in our emergency department (ED) who had low-value blood cultures obtained, and 3) describe this cohort and assess the proportion of true bacteremia in low-value blood cultures.

The study team reviewed the literature and developed consensus criteria to identify conditions in which blood cultures were of low value for our study population. The criteria were applied retrospectively to well-appearing patients aged from 91 days to 19 years, without a central venous catheter, and evaluated in our ED with a peripheral blood culture from June 2018 to April 2020. Children admitted to the intensive care/hematology-oncology/cardiology/pulmonary units, those transferred from our ED to an outside facility, who transferred to our ED due to a positive blood culture from an outside facility, and repeat visits of a patient within 30 days from a previous visit were excluded from the study. After chart review, children with fever for 7 days or more, who were unvaccinated, immunosuppressed, had implanted devices, had a complex medical history, or had provider concerns for bacteremia/sepsis were excluded.

The study population consisted of 1436 children. Children at risk for bacteremia (n = 718) were excluded. Four hundred twenty-four children had discharge diagnoses not included in our study. There were 294 (20.5%) patients who had low-value cultures per our study criteria. Nine children (9/294, 3.1%) had false-positive blood cultures, and three (3/294, 1.0%) had true-positive blood cultures.

We identified a cohort of patients in our ED with blood cultures obtained when available literature indicates they were of low value.