Utilization and Outcomes of Single and Dual Kidney Transplants from Older Deceased Donors in the United Kingdom

Incidence, Nature and Natural History of Additional Histological Findings in Preimplantation and Implantation Kidney Transplant Biopsies

The quality assurance provided by preimplantation biopsy quantification of chronic damage may allow greater use of kidneys from expanded criteria donors, and thereby expand the deceased donor pool. Preimplantation biopsy may, however, identify additional acute or chronic pathologies not considered in the scoring of chronic damage, and these may influence the decision to implant or discard the kidney. This single-centre retrospective cohort study of a contemporary UK donor population systematically characterised the nature of additional findings in 1,046 preimplantation and implantation biopsies over an eight-year period. A diverse range of findings were identified in 111/1,046 (11%) organs; most frequently diabetic glomerulopathy, focal segmental glomerulosclerosis, (micro)thrombi, neutrophil casts, and immunoglobulin/complement staining. Seventy (63%) of these were transplanted, with subsequent biopsy in 41 (58%) cases confirming that 80% of the initial acute changes had spontaneously resolved, while there was no progression of diabetic glomerulopathy, and the lesions of focal segmental glomerulosclerosis were not identified. Over 75% of assessable grafts with additional histological findings at the time of transplant showed adequate function at one-year following transplant. In conclusion, most histological abnormalities that may be identified in addition to chronic scarring in preimplantation kidney biopsies would not preclude transplantation nor predict poor graft function.

Beyond donation to organ utilization in the UK

PURPOSE OF REVIEW

Optimizing deceased donor organ utilization is gaining recognition as a topical and important issue, both in the United Kingdom (UK) and globally. This review discusses pertinent issues in the field of organ utilization, with specific reference to UK data and recent developments within the UK.

RECENT FINDINGS

A multifaceted approach is likely required in order to improve organ utilization. Having a solid evidence-base upon which transplant clinicians and patients on national waiting lists can base decisions regarding organ utilization is imperative in order to bridge gaps in knowledge regarding the optimal use of each donated organ. A better understanding of the risks and benefits of the uses of higher risk organs, along with innovations such as novel machine perfusion technologies, can help clinician decision-making and may ultimately reduce the unnecessary discard of precious deceased donor organs.

SUMMARY

The issues facing the UK with regards to organ utilization are likely to be similar to those in many other developed countries. Discussions around these issues within organ donation and transplantation communities may help facilitate shared learning, lead to improvements in the usage of scarce deceased donor organs, and enable better outcomes for patients waiting for transplants.

Kidney transplantation from elderly donors (> 70 years): a systematic review

PURPOSE

The incidence of kidney transplants from elderly donors over 70 years of age has increased significantly over the past 10 years to reach 20% of available kidney graft in some European countries. However, there is little data available on the outcomes of transplants from these donors. We performed a systematic review to evaluate the outcomes of transplantation from donors over 70 years of age.

METHODS

A systematic review was performed according to preferred reporting items for systematic reviews and meta-analyses. Medline, Embase, and Cochrane databases were searched to identify all studies reporting outcomes on kidney transplants from donors over 70 years. Due to the heterogeneity of the studies, a meta-analysis could not be performed.

RESULTS

A total of 29,765 patients in 27 studies were included. The mean donors age was 74.79 years, and proportion of kidney graft from women was 53.54%. The estimated 1- and 5-year kidney death-censored graft survivals from donors > 70 years old were, respectively, 85.95 and 80.27%, and the patient survivals were 90.88 and 71.29%. The occurrence of delayed graft function was 41.75%, and primary non-function was 4.67%. Estimated graft function at 1 and 5 years was 36 and 38 mL/min/1.73 m². Paucity data were available on post-operative complications.

CONCLUSIONS

Elderly donors appear to be a reliable source of grafts. However, these transplants are associated with a high rate of delayed graft function without repercussion on long-term graft survival. Allocation strategy to elderly recipients is the main factor of decreased recipient survival.

Delayed Graft Function in Kidney Transplant: Risk Factors, Consequences and Prevention Strategies

Background. Delayed graft function is a frequent complication of kidney transplantation that requires dialysis in the first week posttransplant. Materials and Methods. We searched for the most relevant articles in the National Institutes of Health library of medicine, as well as in transplantation, pharmacologic, and nephrological journals. Results. The main factors that may influence the development of delayed graft function (DGF) are ischemia–reperfusion injury, the source and the quality of the donated kidney, and the clinical management of the recipient. The pathophysiology of ischemia–reperfusion injury is complex and involves kidney hypoxia related to the duration of warm and cold ischemia, as well as the harmful effects of blood reperfusion on tubular epithelial cells and endothelial cells. Ischemia–reperfusion injury is more frequent and severe in kidneys from deceased donors than in those from living donors. Of great importance is the quality and function of the donated kidney. Kidneys from living donors and those with normal function can provide better results. In the peri-operative management of the recipient, great attention should be paid to hemodynamic stability and blood pressure; nephrotoxic medicaments should be avoided. Over time, patients with DGF may present lower graft function and survival compared to transplant recipients without DGF. Maladaptation repair, mitochondrial dysfunction, and acute rejection may explain the worse long-term outcome in patients with DGF. Many different strategies meant to prevent DGF have been evaluated, but only prolonged perfusion of dopamine and hypothermic machine perfusion have proven to be of some benefit. Whenever possible, a preemptive transplant from living donor should be preferred.

Deceased Donor Characteristics and Kidney Transplant Outcomes

Kidney transplantation is the therapy of choice for people living with kidney failure who are suitable for surgery. However, the disparity between supply versus demand for organs means many either die or are removed from the waiting-list before receiving a kidney allograft. Reducing unnecessary discard of deceased donor kidneys is important to maximize utilization of a scarce and valuable resource but requires nuanced decision-making. Accepting kidneys from deceased donors with heterogenous characteristics for waitlisted kidney transplant candidates, often in the context of time-pressured decision-making, requires an understanding of the association between donor characteristics and kidney transplant outcomes. Deceased donor clinical factors can impact patient and/or kidney allograft survival but risk-versus-benefit deliberation must be balanced against the morbidity and mortality associated with remaining on the waiting-list. In this article, the association between deceased kidney donor characteristics and post kidney transplant outcomes for the recipient are reviewed. While translating this evidence to individual kidney transplant candidates is a challenge, emerging strategies to improve this process will be discussed. Fundamentally, tools and guidelines to inform decision-making when considering deceased donor kidney offers will be valuable to both professionals and patients.

The use of marginal kidneys in dual kidney transplantation to expand kidney graft utilization

PURPOSE OF REVIEW

The purpose of this review is to chronicle the history of dual kidney transplantation (DKT) and identify opportunities to improve utilization of marginal deceased donor (MDD) kidneys through DKT.

RECENT FINDINGS

The practice of DKT from adult MDDs dates back to the mid-1990s, at which time the primary indication was projected insufficient nephron mass from older donors. Multiple subsequent studies of short- and long-term success have been reported focusing on three major aspects: Identifying appropriate selection criteria/scoring systems based on pre- and postdonation factors; refining technical aspects; and analyzing longer-term outcomes. The number of adult DKTs performed in the United States has declined in the past decade and only about 60 are performed annually. For adult deceased donor kidneys meeting double allocation criteria, >60% are ultimately not transplanted. MDDs with limited renal functional capacity represent a large proportion of potential kidneys doomed to either discard or nonrecovery.

SUMMARY

DKT may reduce organ discard and optimize the use of kidneys from MDDs. New and innovative technologies targeting ex vivo organ assessment, repair, and regeneration may have a major impact on the decision whether or not to use recovered kidneys for single or DKT.

Dual kidney transplants from adult marginal donors: Review and perspective

The practice of dual kidney transplantation (DKT) from adult marginal deceased donors (MDDs) dates back to the mid-1990s with initial pioneering experiences reported by the Stanford and Maryland groups, at which time the primary indication was estimated insufficient nephron mass from older donors. Multiple subsequent studies of short and long-term success have been reported focusing on three major aspects of DKT: Identifying appropriate selection criteria and developing scoring systems based on pre- and post-donation factors; refining technical aspects; and analyzing mid-term outcomes. The number of adult DKTs performed in the United States has declined in the past decade and only about 60 are performed annually. For adult deceased donor kidneys meeting double allocation criteria, >60% are ultimately not transplanted. Deceased donors with limited renal functional capacity represent a large proportion of potential kidneys doomed to either discard or non-recovery. However, DKT may reduce organ discard and optimize the use of kidneys from MDDs. In an attempt to promote utilization of MDD kidneys, the United Network for Organ Sharing introduced new allocation guidelines pursuant to DKT in 2019. The purpose of this review is to chronicle the history of DKT and identify opportunities to improve utilization of MDD kidneys through DKT. This article is protected by copyright. All rights reserved.

Long-term survival benefit from dual kidney transplantation using kidneys from donors with very extended criteria - A French cohort between 2002 and 2014

BACKGROUND

This national multicenter retrospective cohort study aimed to assess the long-term outcomes of dual kidney transplantation (DKT) and compare them with those obtained from single kidney transplantation (SKT).

METHODS

Our first analysis concerned all first transplants performed between May 2002 and December 2014, from marginal donors, defined as brain death donors older than 65, with an estimated glomerular filtration rate (eGFR) lower than 90 ml/min/1.73m². The second analysis was restricted to transplants adequately allocated according to the French DKT program based on donor eGFR: DKT for eGFR between 30 and 60, SKT for eGFR between 60 and 90 ml/min/1.73m². Recipients younger than 65 years or with a panel-reactive antibody percentage ≥ 25% were excluded.

RESULTS

The first analysis included 461 DKT and 1131 SKT. DKT donors were significantly older (77.6 versus 74 years), had a more frequent history of hypertension and a lower eGFR (55.1 versus 63.6 ml/min/1.73m²). While primary nonfunction and delayed graft function did not differ between SKT and DKT, 1-year eGFR was lower in SKT recipients (39 vs. 49 ml/min/1.73m², P < 0.001). Graft survival was significantly better in DKT, even after adjustment for recipient and donor risk factors. Nevertheless, patient survival did not differ between these groups. The second analysis included 293 DKT and 687 SKT adequately allocated with donor eGFR and displayed similar results but with a smaller benefit in terms of graft survival.

CONCLUSIONS

In a context of organ shortage, DKT is a good option for optimizing the use of kidneys from very expanded criteria donors.

Staggered Dual Kidney Transplantation

We describe a case where a patient received a successful dual kidney transplantation in a staggered fashion. Two kidneys from a deceased donor were accepted for 2 separate primary intended recipients, however, due to unforeseen circumstances, both kidneys were eventually transplanted in a staggered fashion into an alternate single recipient. The intention behind this method was to enhance the patient's renal function and to prevent the wastage of a kidney. Despite the significantly prolonged cold ischemia times, the recipient has excellent dual graft function after 3 years. The positive outcome underpins the effectiveness of donor kidneys even with prolonged cold ischemia times outside established best practice guidelines. It also reinforces the effectiveness of dual kidney transplantation. Transplant professionals encounter complex situations occasionally where an established evidence-base or aids to decision-making are limited. This case reflects challenges in decision-making, patient counselling and consent, especially when the opportunity for the staggered dual kidney transplantation, with potential increased morbidity, came about as another recipient declined a usable kidney. It also highlights the widely differing risk appetites of different patients. Crucially, it optimised the donation process and procurement of 2 kidneys while preventing wastage. To our knowledge, this is the first report of a staggered dual kidney transplantation in a single recipient.

Organ donation and transplantation: a multi-stakeholder call to action

Although overall donation and transplantation activity is higher in Europe than on other continents, differences between European countries in almost every aspect of transplantation activity (for example, in the number of transplantations, the number of people with a functioning graft, in rates of living versus deceased donation, and in the use of expanded criteria donors) suggest that there is ample room for improvement. Herein we review the policy and clinical measures that should be considered to increase access to transplantation and improve post-transplantation outcomes. This Roadmap, generated by a group of major European stakeholders collaborating within a Thematic Network, presents an outline of the challenges to increasing transplantation rates and proposes 12 key areas along with specific measures that should be considered to promote transplantation. This framework can be adopted by countries and institutions that are interested in advancing transplantation, both within and outside the European Union. Within this framework, a priority ranking of initiatives is suggested that could serve as the basis for a new European Union Action Plan on Organ Donation and Transplantation.