Blood Culture Contamination and Subsequent Unnecessary Health Care Utilization in Pediatrics

Although contaminated blood cultures are known to result in billions of dollars in annual health care costs in the United States due to excess health care utilization and antibiotic exposure, the burden in pediatrics is not well described.

Retrospective cohort study of 128 524 blood cultures obtained from 2010 to 2022 in outpatient and hospital settings in a multicenter health care system. Cultures with commensal organisms were considered contaminated after excluding patients with high-risk conditions, including immunodeficiencies, malignancy, and indwelling catheters. Health care utilization and cost assessment were analyzed and compared between patients with contaminated blood cultures and patients with true positive or negative blood cultures.

Contaminated blood cultures resulted in 15-fold (odds ratio [OR] = 15.10; 95% CI: 13.50-17.00) higher odds of emergency department (ED) visits, 6-fold (OR = 5.71; 95% CI: 4.63-7.05) higher odds of admissions, and 32% longer length of stay (risk ratio = 1.32; 95% CI: 1.26-1.39) compared with age-matched noncontaminated negative blood cultures. This resulted in approximately $980 in ED costs per contaminant for outpatients and $2500 in hospital costs per contaminant for inpatients, a total of $1.5 million in ED costs over the study. Patients with contaminated cultures received more antibiotics and underwent more blood draws than patients with negative blood cultures.

Pediatric blood culture contamination results in excess reutilization with significant economic costs and impact on patients.