Multidrug-resistant donor-derived infections in solid organ transplantation: a systematic review and meta-analysis of transmission risk factors.

PURPOSE: Donor-derived infections (DDIs) caused by multidrug-resistant organisms (MDROs) are rare but potentially devastating complications of solid organ transplantation (SOT), with limited evidence on transmission risk and clinical outcomes. METHODS: We conducted a systematic review in accordance with PRISMA 2020 guidelines, including case reports, case series, and cohorts describing SOT donors with MDRO that reported recipient's infection outcomes (1999-2025). Individual-level data were extracted when available. Meta-analyses of proportions were performed, and bivariable and multivariable logistic regression models were used to identify factors independently associated with DDI and mortality. RESULTS: 46 studies comprising 435 donors and 544 transplants were included. Kidney (43.8%), lung (29.2%), and liver transplants (22.7%) were the most frequent. Carbapenem-resistant Enterobacterales (38.9%) predominated in donor isolates. The overall transmission rate was 26.6% (IC95%: 14.3-44.2) despite targeted antimicrobial prophylaxis in 86.5% of high-risk recipients. In multivariable analyses, positive preservation fluid (PF) cultures (p < 0.001), high-risk donor's cultures (p < 0.001), and liver transplantation (p = 0.02) were independently associated with increased transmission, whereas positive culture at screening donation (p < 0.001) and carbapenem resistant Acinetobacter baumannii (p = 0.02) isolation was associated with a lower risk of transmission. Respiratory donor cultures (p = 0.006) were independently associated with transmission in lung transplant-specific models. CONCLUSIONS: MDRO in SOT donors are associated with high transmission rates. PF for all SOT and respiratory cultures in lung transplant are key predictors of transmission, supporting organ- and site-specific donor screening and microbiological surveillance to mitigate transmission.