Combined AlloSure and AlloMap Testing in Multi-Organ Heart Transplantation Rejection Surveillance

Purpose AlloSure test is a non-invasive blood test designed to detect the presence of donor cell-free DNA in the recipients blood as a measure of the probability of rejection in heart transplant recipients. The result is displayed as a percent of donor-derived cell-free DNA (dd-cfDNA) in the totalcell-free DNA (cfDNA). Recommended threshold of 0.2% dd-cfDNA has been predictive of low likelihood of rejection. There is no data looking at its value and validation in multi-organ transplant. We aimed to study this area by reviewing our transplant database. Methods All patients who received more than one solid organ transplant at our center and had AlloSure testing were included. Study outcomes included one year survival, rejection grade 2R or more, and hemodynamically significant graft dysfunction. Results There were (7) patients included in the study, average AlloSure score was 0.93% ±0.61% with an average AlloMap score of 33.8±2.14. Four patients (57.1%) had heart and kidney transplant, 3 patients (42.9%) had heart and liver transplantation. Average AlloSure score for heart/kidney transplant recipients was 0.52±0.17% with an average AlloMap score of 33.6±2.28. The while average AlloSure score for heart/liver transplant recipients was 1.21±0.55% mean AlloMap score of 33.93±2.32. None of our patients had graft dysfunction or biopsy-proven rejection >=2R. Survival rate was 100% for the first year in our patients Conclusion AlloSure levels were higher in heart-liver vs. heart-kidney recipients, and in both cohorts higher than the 0.2% threshold recommended for heart transplant prediction of rejection, however did not predict rejection. In our cohort, while AlloMap scores were consistent in both groups, (33.93±2.32 vs. 33.6±2.28 respectively). Elevated AlloSure was not predictive of rejection in multiorgan heart transplant recipients.