Ohara, Stephanie Y

Despite improvements in kidney transplantation rates, the shortage of donor kidneys remains a critical issue, exacerbated by non-utilization of recovered kidneys due to quality concerns, necessitating advancements in perfusion methods to enhance graft outcomes and usage. Although static cold storage remains the default standard for kidney preservation, newer methods like hypothermic machine perfusion have shown improved outcomes, including reduced delayed graft function and better survival rates. Hypothermic oxygenated machine perfusion and normothermic machine perfusion offer some potential clinical benefits but studies to date have demonstrated mixed results. In the United States, LifePort and the XVIVO’s Kidney Assist Transport are the most popular hypothermic perfusion devices, with NMP devices mostly in trials. Combining perfusion with biomarkers such as mitochondrial flavin mononucleotide, neutrophil gelatinase-associated lipocalin, and osteopontin shows promise in assessing kidney viability and predicting post-transplant outcomes, though further research is also needed. Emphasis on repair biomarkers, such as uromodulin and osteopontin, aims to better predict graft outcomes and develop new therapies. While notable advancements have been made in the use of machine perfusion and viability testing for liver transplantation, additional research with larger sample sizes is essential to substantiate these results and enhance kidney transplantation outcomes.

ABSTRACT Introduction Donation after circulatory death (DCD) allografts are underutilized in liver transplantation (LT) due to increased risk of complications. These risks stem from ischemic injury sustained during the total donor warm ischemia time (tDWIT), historically limited to 30 min. Normothermic machine perfusion (NMP) can mitigate these risks and facilitate LT of DCD grafts with extended tDWIT. We aimed to compare outcomes of DCD allografts with extended tDWIT preserved on NMP versus static cold storage (SCS). Methods This single‐center study included adult DCD LT with tDWIT ≥ 30 from 2019 to 2023. Outcomes of NMP and SCS were compared including EAD, IC, graft survival, and patient survival. Results Among 68 DCD LT with tDWIT ≥ 30, 64.7% ( n = 44) were preserved with NMP and 35.3% ( n = 24) with SCS. No differences in donor or recipient demographics were observed. The median tDWIT was 33 min for NMP and 30.5 min for SCS ( p < 0.01). Despite longer tDWIT, the NMP group had lower rates of EAD (4.5% vs. 66.7%, p < 0.01) and IC (2.3% vs. 29.2%, p < 0.01). One‐year graft survival was higher in NMP ( p < 0.01), and 1‐year patient survival was comparable between groups ( p = 0.18). Conclusion NMP challenges traditional tDWIT constraints and can increase the pool of viable DCD allografts for transplantation.

AbstractIntroductionExpedited out‐of‐sequence deceased donor kidney allocation is a strategy to avoid discards after early placement attempts have been unsuccessful. Our study aimed to assess outcomes and characteristics of these transplanted kidneys.MethodsKDPI matching was performed between expedited allocation (EA) and standard allocation (SA) deceased donor kidney transplants performed at our center.ResultsBetween 2018 and 2021, there were 225 EA offers, and 189 (84%) were transplanted. EA recipients were older (p = .007) and had shorter dialysis vintage (p < .0001). EA kidneys were likely to be nationally allocated (p < .001), have AKI (p < .0001) and longer CIT (p < .0001). There were no differences in EA and SA time‐zero kidney biopsies (ci, p = .07; ct, p = .89; cv, p = .95; ah, p = .79). EA kidneys had more DGF (p = .0006), but there were no differences in DGF duration (p = .83), hospital length of stay (p = .43), 1‐ and 2‐year eGFR (p = .16, p = .99), patient (p = .34), or death‐censored graft (p = .66) survival.ConclusionDuring this study period, our center transplanted 189 kidneys through EA following local‐regional declines. These kidneys often came from AKI donors and had more DGF but had similar outcomes to KDPI‐matched SA kidneys. Although it has been suggested that EA has the potential to worsen transplant disparities, transplant center level decisions on organ acceptance contribute to these variations.

AbstractDual kidney transplantation (DKT), utilizing two adult kidneys from the same donor for one recipient, has been used as a way to expand the available donor pool. These kidneys often come from high Kidney Donor Profile Index donors (KDPI > 85%). Data comparing outcomes between high KDPI DKT and single kidney transplants (SKT) remain limited. We assessed outcomes of 336 high KDPI kidney transplants performed at our center; 11.0% (n = 37) were DKT. Recipients of DKT were older (P = .02) and donors had a higher KDPI score (median 96% vs. 91%, P < .0001). DKT operative time was higher compared to SKT (+1.4 hours, P < .0001). There were no differences in delayed graft function (54.1% vs. 51.5%, P = .77) and hospital length of stay (median 4.0 vs. 3.0 days, P = .21) between DKT and SKT. Grade I Clavien‐Dindo complications occurred in 8.1% of DKT and 13.7% of SKT (P = .008). There were no grade IVa, IVb, or V complications in either group. DKT had more glomerulosclerosis (P = .04), interstitial fibrosis (P = .02), tubular atrophy (P = .01), and arterial thickening (P = .03) on 1‐year protocol biopsies. Estimated glomerular filtration was higher for DKT at 1‐ (P = .004) and 2‐years post‐transplant (P = .01). There were no differences in patient (HR 1.3, 95% CI .5‐3.3, P = .58) or graft (HR 1.1, 95% CI .5‐2.3, P = .83) survival. Good outcomes can be achieved with DKT using high KDPI kidneys with moderate chronic changes. DKT is a good option to help further utilize high KDPI kidneys and minimize discard.