Riad, Samy

Outcomes of kidney-alone transplantation (KAT) in former simultaneous liver-kidney (SLK) transplant candidates after liver waitlist delisting are not well defined. Using Scientific Registry of Transplant Recipients (SRTR) data, we identified adult recipients who underwent KAT between 2005 and 2025 after prior SLK listing (RLD-KAT), which was matched 1:5 to primary KAT recipients without liver disease by age, transplant year, and diabetes status. Patient and graft survival were evaluated using the Kaplan-Meier method and multivariable Cox proportional hazards models. We identified 163 RLD-KAT recipients matched to 815 controls. Unadjusted Kaplan-Meier analyses demonstrated lower patient survival in RLD-KAT (p = 0.020), whereas death-censored and overall graft survival were similar (p > 0.05). In multivariable models, death-censored graft survival (HR 0.89; 95% CI 0.51–1.53), overall graft survival (HR 1.00; 95% CI 0.73–1.36), and patient survival (HR 1.07; 95% CI 0.76–1.5) did not differ significantly. Six RLD-KAT recipients (3.7%) subsequently underwent liver transplantation. Kidney-alone transplantation in prior SLK candidates was associated with acceptable patient and graft outcomes and a low incidence of subsequent liver transplantation.

Delayed graft function (DGF) is a frequent complication after deceased donor kidney transplantation, yet its long-term impact remains understudied. Heterogeneous populations, short follow-up, and inadequate control of donor-related factors have limited prior studies. Using the Scientific Registry of Transplant Recipients (2005–2024), we evaluated the association between DGF and long-term graft outcomes, including a mate-kidney (same donor, discordant DGF status) analysis to isolate its independent effect. We identified 103,678 dialysis-dependent deceased donor kidney recipients maintained on tacrolimus and mycophenolate. Mixed-effects Cox models, adjusted for donor, recipient, immunologic, and procurement factors. DGF occurred in 30.1% of recipients and was associated with increased death-censored graft failure (HR 1.40; 95% CI 1.33–1.47) and overall graft failure (HR 1.27; 95% CI 1.23–1.31). DGF recipients had higher rejection rates at 6 (6.0% vs. 4.7%) and 12 months (8.9% vs. 7.3%), longer hospital stay, and higher 1-year rehospitalization. In the mate-kidney analysis (6,818 donors), DGF remained strongly associated with death-censored graft failure (HR 1.58; 95% CI 1.39–1.80) and overall graft failure (HR 1.35; 95% CI 1.25–1.46), confirming the independent effect of DGF. DGF is a strong predictor of adverse long-term outcomes irrespective of rejection and warrants targeted prevention strategies and intensified follow-up.

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. Delayed graft function (DGF) in deceased-donor kidney transplantation increases morbidity, prolongs hospitalization, and increases healthcare costs. Hypothermic machine perfusion (HMP) has emerged as a promising strategy to reduce DGF; however, large-scale real-world data remain limited. Methods. We performed a retrospective cohort analysis using the Scientific Registry of Transplant Recipients (2014–2024), including adult dialysis-dependent recipients of deceased-donor kidneys preserved using either static cold storage (SCS) or HMP. The primary outcome was DGF, defined as dialysis requirement within 7 d posttransplant. A matched-pairs analysis was conducted using kidneys from the same donor. Results. The overall cohort included 59 859 recipients (46.8% SCS, 53.2% HMP), with 2208 matched pairs identified. In the overall cohort, HMP grafts had longer cold ischemia times and a higher kidney donor risk index. They were more frequently obtained from older and donation after circulatory death donors. Although the overall DGF incidence was higher with HMP (34.4% versus 30.9%, P < 0.001), matched-pairs analysis revealed significantly lower DGF rates with HMP (29.8% versus 36.1%, P < 0.001). Adjusted analyses identified HMP as protective against DGF (overall cohort odds ratio, 0.71; 95% confidence interval, 0.66-0.78; paired cohort OR, 0.68; 95% CI, 0.50-0.93). Additional modifiable risk factors include prolonged cold ischemia time, higher recipient body mass index, and longer dialysis duration. Conclusions. This real-world study demonstrates that HMP is associated with a significant reduction in DGF risk in kidney transplantation compared with SCS, supporting its broader implementation and targeted management of modifiable risk factors.

Background. Living kidney donation (KD) evaluation particularly focuses on glomerular filtration rate (GFR). Assessing GFR in living kidney donors can be done by estimation (eGFR) or measurement (mGFR). This study aims to evaluate the impact of eGFR equations, focusing on the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2021 equation for donor eligibility screening and the reclassification of donors excluded by eGFR criteria to mGFR assessments. Methods. Retrospective, single-center observational study of 2512 kidney donors evaluated between 2011 and 2023, at the Mayo Clinic. We performed analyses and comparisons of 4 eGFR formulae and 2 mGFR methods in terms of performance, eligibility criteria according to Kidney Disease: Improving Global Outcomes guidelines/age-adjusted criteria, eligibility reclassification, and subgroup analyses. Results. The CKD-EPI 2021 resulted in a higher percentage of patients being eligible for KD (81.4%) and achieved the highest P10 (32%–34%) and P30 (87%–88%) across all mGFR methods. When patients were deemed eligible for donation by any eGFR formula, 95% retained this status on reassessment with mGFR. Conversely, when an eGFR formula classified a patient as ineligible, this was revised to be eligible in about 90% of cases on reassessment with mGFR, with a higher reclassification rate observed when the IoCl was used instead of CrCl. Conclusions. The CKD-EPI 2021 performs best for screening potential KD. If a KD is deemed ineligible by CKD-EPI 2021, there is a high likelihood that they will be reclassified as eligible when assessed with mGFR. This study strongly supports using mGFR in donor evaluations, especially when the eGFR does not meet the criteria to ensure equity of access to being a living donor.

ABSTRACT Background The association between transjugular intrahepatic portosystemic shunt TIPS and waitlist outcomes in simultaneous liver‐kidney (SLK) transplant recipients remains unclear. Methods Between 2003 and 2023, we examined the scientific registry of transplant recipients. All adult candidates with overlapping waiting lists for liver and kidney transplants ( N = 15 087) were analyzed (entire cohort). Candidates without TIPS ( n = 13 980) and with ( n = 1107) were followed through November 30, 2023, and the following outcomes were analyzed: death, SLK transplant, liver‐ or kidney‐alone transplant, or removal from the list. The Aalen–Johansen method was used to calculate the cumulative incidence rates of the outcomes, where the outcomes were considered competing risks. Mixed effects Cox proportional hazard models were used to compare the outcomes by TIPS status. We separately analyzed dialysis‐dependent candidates ( n = 10 370). Results In the entire cohort, the 1‐year cumulative incidence of death in those without TIPS was higher than in those with (12.5% vs. 9%). In the dialysis‐dependent cohort, the 1‐year death incidence was 13.3% versus 8.8% in those without TIPS and those with, respectively. In the multivariable Cox proportional hazard models, TIPS was associated with a 29% lower mortality risk in the entire cohort (HR = 0.71, 95% CI: 0.60–0.84, p < 0.001) and a 33% lower risk of mortality in the dialysis‐dependent cohort. The likelihood of receiving SLK was lower for recipients with TIPS in the univariable analysis. However, this association was attenuated after adjustment. The causes of removal were similar irrespective of TIPS status in both cohorts. Conclusion In this large cohort of SLK candidates, those with TIPS had a better waitlist survival, irrespective of their dialysis requirements before transplantation. Prospective studies are needed to validate these findings.