Variation in blood culture testing in children hospitalized with three common infections

Routine blood culture (BCx) testing in uncomplicated community-acquired pneumonia (CAP), skin and soft tissue infections (SSTI), and urinary tract infections (UTI) has demonstrated low clinical utility.

To evaluate hospital-level BCx testing trends and their association with clinical outcomes for children hospitalized with CAP, SSTI, and UTI.

This retrospective cohort study used the Pediatric Health Information System database to identify hospitalizations of children aged 3 months-18 years with CAP, SSTI, and UTI from 2016 to 2024. We excluded patients with complicated infections, complex chronic conditions, intensive care unit admission, or length of stay (LOS) > 7 days. Hospital-level BCx testing rates were calculated by infection type, and annual trends were examined. Hospitals were grouped into low, moderate, and high BCx testing groups. Outcomes including LOS, costs, readmissions, and emergency department revisits were compared across hospital groups, adjusting for infection type, age, and illness severity.

Among 133,783 encounters across 37 hospitals, BCxs were obtained in 42% hospitalizations for CAP, 46% for SSTI, and 56% for UTI hospitalizations with substantial hospital-level variation (e.g., 14%-77% for CAP). Over time, four hospitals showed significant increases, eight showed decreases, and 25 showed no change in annual BCx testing. No clinically significant differences in outcomes were observed across low (n = 15), moderate (n = 14), or high (n = 8) hospital testing groups.

BCx testing remains frequent for CAP, SSTI, and UTI with a minority of hospitals demonstrating testing reductions over time. The frequency of BCx testing and lack of significant differences in outcomes suggests opportunities for diagnostic stewardship.