T1. Studies of pre-transplant screening and evaluation
Emily A. Blumberg, MD
Professor of Medicine, ID Fellowship Program Director, Director Transplant Infectious Diseases
Perelman School of Medicine at the University of Pennsylvania
Disclosure: bristol myers squibb: DSMB member for belatacept, Other Financial or Material Support
Merck: Advisory Board, Grant/Research Support
Shire: Grant/Research Support
Background : Transplant guidelines recommend exercising caution when considering organs that may be infected or colonized with multidrug-resistant organisms (MDROs) and treating the organ recipient with perioperative antibiotics active against the donor MDRO. Unfortunately, donor MDROs are often identified only after transplantation. We developed a clinical prediction tool to stratify donors’ MDRO risk at the time of donor evaluation.
Methods : A retrospective cohort study was conducted at four transplant centers in Philadelphia between 1/1/2015-6/30/2016. All deceased organ donors who donated ≥ 1 organ to one of the centers were included. Multivariate logistic regression was used to determine predictors of donor MDROs, including methicillin-resistant S. aureus (MRSA), vancomycin-resistant enterococci, extended-spectrum cephalosporin-resistant (ESC-R) or carbapenem-resistant Enterobacteriaceae, multidrug-resistant (MDR) P. aeruginosa, or MDR Acinetobacter species. Manual forward selection was utilized to maximize the area under the receiver operating characteristic curve (AUC). A scoring system was developed based on the odds ratios for each covariate. Internal validity was assessed using the Hosmer-Lemeshow statistic, specificity, and negative predictive value (NPV).
Results : Of 440 total donors, 62 (14%) grew MDROs on culture. The majority were MRSA (40) or ESC-R Enterobacteriaceae (20). The most parsimonious model that predicted donor MDROs included: a terminal hospitalization ≥ 7 days (1 point), ≥ 2 antibiotics administered during the terminal hospitalization (1 point), receipt of extracorporeal membrane oxygenation (ECMO) (1 point), and presence of opacities on donor chest imaging concerning for lower respiratory tract infection (2 points). With this scoring system, the maximum attainable score is 5; any donor with a score of ≥ 2 points would be considered high risk for an MDRO, with an AUC of 0.71, specificity of 99%, and NPV of 86%. The Hosmer-Lemeshow P=0.68.
Conclusion : The risk of an MDRO among deceased organ donors can be predicted using the above scoring system. This tool will inform decisions about organ utilization and perioperative prophylaxis for solid organ transplant recipients.