Epidemiology of adult deceased solid organ donors with positive blood cultures in the USA: a retrospective registry-based study

Background Organs from donors with positive blood cultures (BCx) have been shown to increase the risk of donor-derived infections. However, the percentage of BCx positivity in donors remains uncertain. Methods We conducted a retrospective analysis using data from the United Network for Organ Sharing, examining adult donors in the U.S. from 2014 to 2024. Organisms were classified into five mutually exclusive categories: Gram-positive, Gram-negative, anaerobes, suspected contamination, and Candida species. The primary outcome was the annual percentage of donors with positive BCx. The secondary outcome was to identify factors associated with BCx positivity within the first two days of admission. Findings Between 2014 and 2024, the percentage of donors with positive BCx increased, rising from 7.0% in 2014 to 13.5% in 2024. The percentage of organisms also increased: Gram-positive (3.8%–6.3%), suspected contaminants (2.9%–6.6%), and Gram-negative (0.84%–1.6%). Donors who were older, male and Black (vs. White) had increased odds of any positive BCx and coagulase-negative Staphylococcus (CoNS). Compared to intracranial hemorrhage/stroke, donor death from drowning had increased odds of Gram-negative (OR 3.40, 95% CI: 1.57–7.36) and anaerobic organisms (OR 5.78, 95% CI: 1.35–24.7). Donors with heavy alcohol use had increased odds of Streptococcus pneumoniae (OR 1.39, 95% CI: 1.08–1.79). Donors with Public Health Service risk had increased odds of Staphylococcus aureus (OR 2.20, 95% CI: 1.84–2.62). Compared to donation after brain death, donation after circulatory death had increased odds of S. aureus (OR 1.29, 95% CI: 1.10–1.52). Donors with higher social deprivation index (lower socioeconomic status) had increased odds of any positive BCx (OR 1.03, 95% CI: 1.02–1.04) and CoNS (OR 1.05, 95% CI: 1.03–1.06). Interpretation This study presents the first national-level epidemiological data on donor blood cultures. Our findings indicate that the percentage of donors with positive BCx has increased over time, and community-acquired bacteremia is associated with donor-related factors. Funding There was no funding source for this study.