Kandaswamy, Raja

Background. Donor-derived cell-free DNA (dd-cfDNA) has emerged as a promising noninvasive biomarker for detecting allograft rejection in solid organ transplantation. However, its diagnostic utility in pancreas transplantation, including in multiorgan recipients, remains underexplored. Methods. We conducted a retrospective analysis of 42 pancreas transplant recipients (38 simultaneous pancreas-kidney, 4 pancreas transplant alone) who underwent for-cause organ biopsy and dd-cfDNA testing between April 2020 and December 2024. dd-cfDNA was measured using the Prospera assay, with a threshold of ≥1% considered high risk and <1% low-risk. Biopsy results were correlated with dd-cfDNA to assess test performance. Results. A total of 50 dd-cfDNA tests and 45 organ biopsies were analyzed. Among simultaneous pancreas-kidney recipients, dd-cfDNA demonstrated a sensitivity of 86.7%, specificity of 52.2%, positive predictive value (PPV) of 54.2%, and negative predictive value (NPV) of 85.7% for rejection. In pancreas transplant alone recipients, all high-risk dd-cfDNA results corresponded to biopsy-proven rejection, yielding 100% sensitivity, specificity, PPV, and NPV. When combining both cohorts, dd-cfDNA testing achieved an overall sensitivity of 88.2%, specificity of 57.7%, PPV of 57.7%, and NPV of 88.2%. Additionally, dd-cfDNA kinetics suggested its potential utility as a surveillance tool posttreatment, potentially reducing the need for closure biopsies. Conclusions. dd-cfDNA is a valuable noninvasive adjunct for monitoring of rejection in pancreas transplant recipients. Further prospective studies are needed to validate these findings and define the optimal role of dd-cfDNA in posttransplant care.

ABSTRACT This study investigated the association between induction type and long‐term outcomes in kidney retransplant recipients who experienced graft loss due to BK virus–associated nephropathy (BKVAN). Using Scientific Registry of Transplant Recipients data (2003–2021), we identified 277 adult kidney‐alone retransplant recipients with BKVAN‐related graft loss and categorized them by induction regimen: depletional ( n = 217) and nondepletional ( n = 60). The groups were similar overall, except the nondepletional cohort had lower panel‐reactive antibodies, a shorter time between transplants, and more live donor kidneys. Kaplan–Meier curves assessed 10‐year recipient and graft survival, and Cox proportional hazards models, adjusted for key donor and recipient factors, evaluated associations between induction type and outcomes. Rates of delayed graft function, one‐year rejection, and estimated glomerular filtration rate were comparable between groups. Ten‐year recipient and death‐censored graft survival did not differ by induction type (recipient survival: HR 1.09; 95% CI 0.43–2.77; p = 0.85; graft survival: HR 0.85; 95% CI 0.24–2.97; p = 0.79). Recurrent BKVAN‐related graft failure occurred only in the depletional group (5 of 217; 2.3%), while rejection‐related graft failure was more common in the nondepletional group (5 of 60; 8.3% vs. 6 of 217; 2.8%). Although these differences did not translate into long‐term graft survival disparities, they highlight the competing risks of viral recurrence and rejection. Thus, clinicians should interpret these results with caution and weigh the risks and benefits of induction choice in retransplant recipients with prior BKVAN, recognizing that this observational study cannot establish causality.

Background. Long-term outcome data by induction type in simultaneous pancreas-kidney (SPK) is limited. Methods. Utilizing the Scientific Registry of Transplant Recipients, we examined all primary SPK transplants between 2000 and 2020, excluding crossmatch-positive recipients. We grouped recipients according to induction regimen into 3 groups: rabbit anti-thymocyte globulin (r-ATG) (n = 5678), alemtuzumab (n = 1199), and interleukin-2 receptor antagonist (IL-2RA; n = 1593). We analyzed the 10-y recipient and composite (kidney and pancreas) graft survival using the Kaplan-Meier survival function. Cox-proportion hazard models were generated to examine the association between induction type, the 10-y recipient, and graft survival. Models were adjusted for recipient age, sex, ethnicity, HLA-mismatch, diabetes type, dialysis dependency, cold-ischemia time, local versus imported organs, panel reactive antibody, steroid maintenance, and Pancreas Donor Risk Index. Results. r-ATG was associated with the lowest 1-y kidney and pancreas rejection rates compared with other agents (P < 0.001). In the univariable analysis, induction type was not associated with recipient (log-rank P = 0.11) or graft survival (log-rank P = 0.36). In the multivariable model for the composite graft survival, alemtuzumab use was associated with 22% increased kidney or pancreas graft loss compared with r-ATG (adjusted hazard ratio, 1.22; 95% confidence interval, 1.05–1.42), whereas IL-2RA use was not a predictor of graft survival. Induction type did not influence recipient survival in the adjusted model. Conclusions. r-ATG use was associated with the lowest SPK rejection rates. Compared with r-ATG, alemtuzumab but not IL-2RA was associated with worse long-term death-censored SPK graft outcome. Our analysis supports the common use of r-ATG for induction in US primary SPK recipients.