Kidney transplantation from donors after cardiac death: a 25-year experience. Transplantation. 2010;90:1106-1112. [PMID: 20861804 DOI: 10.1097/tp.0b013e3181f83b0b]

How to Best Protect Kidneys for Transplantation-Mechanistic Target

The increasing number of patients on the kidney transplant waiting list underlines the need to expand the donor pool and improve kidney graft utilization. By protecting kidney grafts adequately from the initial ischemic and subsequent reperfusion injury occurring during transplantation, both the number and quality of kidney grafts could be improved. The last few years have seen the emergence of many new technologies to abrogate ischemia-reperfusion (I/R) injury, including dynamic organ preservation through machine perfusion and organ reconditioning therapies. Although machine perfusion is gradually making the transition to clinical practice, reconditioning therapies have not yet progressed from the experimental setting, pointing towards a translational gap. In this review, we discuss the current knowledge on the biological processes implicated in I/R injury and explore the strategies and interventions that are being proposed to either prevent I/R injury, treat its deleterious consequences, or support the reparative response of the kidney. Prospects to improve the clinical translation of these therapies are discussed with a particular focus on the need to address multiple aspects of I/R injury to achieve robust and long-lasting protective effects on the kidney graft.

Thymoglobulin versus Alemtuzumab versus Basiliximab Kidney Transplantation from Donors After Circulatory Death

Introduction

The Campath, Calcineurin inhibitor (CNI) reduction, and Chronic allograft nephropathy (3C), a study comparing alemtuzumab versus basiliximab induction immunosuppression in kidney transplants, has found lower acute rejection rate with alemtuzumab but same graft survival. The aim of the current study is to evaluate the effect of induction immunosuppression (thymoglobulin, alemtuzumab, basiliximab) on the outcome of kidneys of donors after circulatory death (DCD).

Methods

Data of the 274 DCD patients of the 3C obtained from the sponsor were compounded with the 140 DCD patients who received thymoglobulin in a single center with the same entry criteria as the 3C, giving 414 patients on 3 induction regimes.

Results

There were more male donors (P < 0.05) and human leukocyte antigen and DR mismatched patients in the thymoglobulin group (P < 0.001). Death-censored graft survival at 6 months was 98.6% in the thymoglobulin, 95.5% in the alemtuzumab (P = 0.08), and 95.7% in the basiliximab group (P = 0.09) and at 2 years 97.9% versus 94.8% (P = 0.13, hazard ratio [HR] 2.8, 95% CI 0.7–10.9) versus 94.3% (P = 0.06, HR 3.5, 95% CI 0.9–13.6), respectively.

The 2-year overall graft survival was 95% in the thymoglobulin versus 88% in the alemtuzumab (unadjusted P = 0.038, adjusted HR 2.4, 95% CI 0.99–5.9) and 91.4% in the basiliximab group (P = 0.21). The 2-year patient survival was numerically less in the alemtuzumab compared with the thymoglobulin group (91.8% vs. 97.1%, P = 0.052, HR 2.90, 95% CI 0.93–9.2). Acute rejection was 17% in the basiliximab, 4.3% in the thymoglobulin, and 6% in the alemtuzumab group (P < 0.001).

Conclusion

In DCD transplants, thymoglobulin induction may provide advantage over alemtuzumab in patient survival and the same advantage as alemtuzumab over basiliximab in terms of acute rejection. Differing maintenance immunosuppression may contribute to the difference found.

Pre-transplant donor-specific HLA antibodies and risk for poor first-year renal transplant outcomes: results from the Swiss Transplant Cohort Study

The aim of this study was to analyze first year renal outcomes in a nationwide prospective multicenter cohort comprising 2215 renal transplants, with a special emphasis on the presence of pre-transplant donor-specific HLA antibodies (DSA). All transplants had a complete virtual crossmatch and DSA were detected in 19% (411/2215). The investigated composite endpoint was a poor first-year outcome defined as (i) allograft failure or (ii) death or (iii) poor allograft function (eGFR ≤25 ml/min/1.73 m² ) at one year. Two hundred and twenty-one (221/2215; 10%) transplants showed a poor first-year outcome. Rejection (24/70; 34%) was the most common reason for graft failure. First-year patient's death was rare (48/2215; 2%). There were no statistically significant differences between DSA-positive and DSA-negative transplants regarding composite and each individual endpoint, as well as reasons for graft failure and death. DSA-positive transplants experienced more frequently rejection episodes, mainly antibody-mediated rejection (both P < 0.0001). The combination of DSA and any first year rejection was associated with the overall poorest death-censored allograft survival (P < 0.0001). In conclusion, presence of pre-transplant DSA per se does not affect first year outcomes. However, DSA-positive transplants experiencing first year rejection are a high-risk population for poor allograft survival and may benefit from intense clinical surveillance.

When Origin Matters: Properties of Mesenchymal Stromal Cells From Different Sources for Clinical Translation in Kidney Disease

Advanced therapy medicinal products (ATMPs) offer new prospects to improve the treatment of conditions with unmet medical needs. Kidney diseases are a current major health concern with an increasing global prevalence. Chronic renal failure appears after many years of impairment, which opens a temporary window to apply novel therapeutic approaches to delay or halt disease progression. The immunomodulatory, anti-inflammatory, and pro-regenerative properties of mesenchymal stromal cells (MSCs) have sparked interest for their use in cell-based regenerative therapies. Currently, several early-phase clinical trials have been completed and many are ongoing to explore MSC safety and efficacy in a wide range of nephropathies. However, one of the current roadblocks to the clinical translation of MSC therapies relates to the lack of standardization and harmonization of MSC manufacturing protocols, which currently hinders inter-study comparability. Studies have shown that cell culture processing variables can have significant effects on MSC phenotype and functionality, and these are highly variable across laboratories. In addition, heterogeneity within MSC populations is another obstacle. Furthermore, MSCs may be isolated from several sources which adds another variable to the comparative assessment of outcomes. There is now a growing body of literature highlighting unique and distinctive properties of MSCs according to the tissue origin, and that characteristics such as donor, age, sex and underlying medical conditions may alter the therapeutic effect of MSCs. These variables must be taken into consideration when developing a cell therapy product. Having an optimal scale-up strategy for MSC manufacturing is critical for ensuring product quality while minimizing costs and time of production, as well as avoiding potential risks. Ideally, optimal scale-up strategies must be carefully considered and identified during the early stages of development, as making changes later in the bioprocess workflow will require re-optimization and validation, which may have a significant long-term impact on the cost of the therapy. This article provides a summary of important cell culture processing variables to consider in the scale-up of MSC manufacturing as well as giving a comprehensive review of tissue of origin-specific biological characteristics of MSCs and their use in current clinical trials in a range of renal pathologies.

Perceptions held by healthcare professionals concerning organ donation after circulatory death in an Australian intensive care unit without a local thoracic transplant service: A descriptive exploratory study

BACKGROUND AND OBJECTIVE

Organ donation rates continue to be low in Australia compared with demand. Donation after circulatory death (DCD) has been an important strategy to increase donation rates, facilitated by advances in cardiopulmonary support in intensive care units (ICUs). However, DCD may harbour greater logistical challenges and unfavourable perceptions amongst some ICU healthcare professionals. The aim of this study was to evaluate and understand DCD perceptions at an Australian tertiary hospital.

METHODS

This descriptive exploratory study was conducted at an Australian tertiary hospital. Participants were recruited voluntarily for interview via email and word-of-mouth through the hospital's ICU network. The study used a mixed-methods approach; five close-ended questions were included in the form of Likert scales followed by a semistructured interview with open-ended questions designed to understand participants' perceptions of DCD. Interviews were recorded, transcribed, and thematically analysed.

RESULTS

Sixteen participants were interviewed including eight intensive care doctors, four donation specialist nursing coordinators (DSNCs), and four bedside nurses. Likert responses demonstrated clinicians' support for both DCD and donation after brain death (DBD). Thematic analysis of the transcripts yielded three overarching themes including 'Contextual and environmental influences on DCD decision-making', 'Personal difficulties faced by clinicians in DCD decision-making', and 'Family influences on DCD decision-making'. Significant geographical separation between donation and organ retrieval teams, incurring significant resource utilisation, impacted the donation team's decision-making around DCD, as did a perceived disruption of ICU care to facilitate donation especially for cases where successful DCD was identified to be unlikely.

CONCLUSIONS

Overall, DCD was as acceptable to participants as DBD. However, the geographical separation of this centre meant that logistical barriers potentially impacted the DCD process. Open lines of communication with transplant centres, local resourcing, and a culture of education, experience, and leadership may facilitate the DCD programs where distant retrieval is commonplace.

Implementation of donation after circulatory death kidney transplantation can safely enlarge the donor pool: A systematic review and meta-analysis

BACKGROUND

Donation after circulatory death (DCD) kidney transplantation has been introduced to address organ shortage. However, DCD kidneys are not accepted worldwide due to concerns about inferior quality. To investigate whether these concerns are justified, we performed a systematic review and meta-analysis to investigate DCD graft outcomes compared to donation after brain death (DBD).

MATERIALS AND METHODS

EMBASE, Medline, Cochrane, Web of Science and Google Scholar were searched from database inception until September 2020. Exclusion criteria were studies reporting on pediatric/dual kidney transplants, multi-organ transplants or studies including normothermic perfusion techniques. The primary outcome was graft survival. Secondary outcomes were primary non-function (PNF), delayed graft function (DGF), 3-months biopsy-proven acute rejection (BPAR), 1-year estimated Glomerular Filtration Rate (eGFR), patient survival, and urologic complications. A random-effects model was used for meta-analysis. Meta-regression analysis was performed in case of high between-study heterogeneity.

RESULTS

Fifty-one studies were included, comprising 73,454 DCD and 518,229 DBD recipients. One-year graft loss was increased in DCD recipients (death-censored: risk ratio (RR) 1.10 (95%-confidence interval (CI) 1.04-1.16), all-cause: RR 1.13 (95%-CI 1.08-1.19)). Ten-year graft loss was similar to DBD (death-censored: RR 1.02 (95%-CI 0.92-1.13), all-cause: RR 1.03 (95%-CI 0.94-1.13)). DCD recipients had an increased risk of PNF (RR 1.43 (95%-CI 1.26-1.62)), DGF (RR 2.02 (95%-CI 1.88-2.16)), and 1-year mortality (RR 1.10 (95%-CI 1.01-1.21)). No differences were observed for 3-months BPAR, ureter stenosis/leakage, 1-year eGFR and 10-year mortality.

CONCLUSION

Long-term DCD kidney transplant outcomes are similar to DBD despite a higher risk of PNF, DGF, and a 13% increased risk of graft loss in the first year after transplantation. These results should encourage implementation of DCD programs.

Hypothermic oxygenated machine perfusion of the human pancreas for clinical islet isolation: a prospective feasibility study

Due to an increasing scarcity of pancreases with optimal donor characteristics, islet isolation centers utilize pancreases from extended criteria donors, such as from donation after circulatory death (DCD) donors, which are particularly susceptible to prolonged cold ischemia time (CIT). We hypothesized that hypothermic machine perfusion (HMP) can safely increase CIT. Five human DCD pancreases were subjected to 6 h of oxygenated HMP. Perfusion parameters, apoptosis, and edema were measured prior to islet isolation. Five human DBD pancreases were evaluated after static cold storage (SCS). Islet viability, and in vitro and in vivo functionality in diabetic mice were analyzed. Islets were isolated from HMP pancreases after 13.4 h [12.9–14.5] CIT and after 9.2 h [6.5–12.5] CIT from SCS pancreases. Histological analysis of the pancreatic tissue showed that HMP did not induce edema nor apoptosis. Islets maintained >90% viable during culture, and an appropriate in vitro and in vivo function in mice was demonstrated after HMP. The current study design does not permit to demonstrate that oxygenated HMP allows for cold ischemia extension; however, the successful isolation of functional islets from discarded human DCD pancreases after performing 6 h of oxygenated HMP indicates that oxygenated HMP may be a useful technology for better preservation of pancreases.

Early Transplant Arteriopathy in Kidney Transplantation

BACKGROUND

Early dysfunction of renal allografts may be associated with vascular injury, which raises the specter of active rejection processes that require medical intervention. In our practice, we have encountered patients who present with delayed graft function and demonstrate a unique pattern of endothelial cell injury that raises concern for rejection in their biopsy. Therefore, we sought to systematically determine the biopsy characteristics and outcome of these patients.

METHODS

During a 17-year period at the University of Washington in Seattle, United States, we identified 24 cases of a distinct arterial vasculopathy presenting in the first year posttransplantation. This early transplant arteriopathy (ETA) is characterized by endothelial cell swelling and intimal edema but without the intimal arteritis that defines vascular rejection.

RESULTS

Approximately 1% of transplant biopsies during the study period showed ETA, almost all of which were in deceased donor organs (96%), and most presented with delayed graft function (54%) or increased serum creatinine (38%) soon after transplantation (median 13 days; range, 5-139). In this study, 77% of patients were managed expectantly, with only 2 patients (7.6%) subsequently developing acute vascular rejection. Except for 1 patient who died, all patients had functioning allografts at 1 year follow-up.

CONCLUSION

Recognizing ETA and distinguishing it from vascular rejection is important to prevent over-treatment because most patients appear to recover allograft function rapidly with expectant management.

Donor type and 3-month hospital readmission following kidney transplantation: results from the Netherlands organ transplant registry

BACKGROUND

Hospital readmission after transplantation is common in kidney transplant recipients (KTRs). In this study, we aim to compare the risk of 3-month hospital readmission after kidney transplantation with different donor types in the overall population and in both young (< 65 years) and elderly (≥65 years) KTRs.

METHODS

We included all first-time adult KTRs from 2016 to 2018 in the Netherlands Organ Transplant Registry. Multivariable logistic regression models were used to estimate the effect while adjusting for baseline confounders.

RESULTS

Among 1917 KTRs, 615 (32.1%) had at least one hospital readmission. Living donor kidney transplantation (LDKT) recipients had an adjusted OR of 0.76 (95%CI, 0.61 to 0.96; p = 0.02) for hospital readmission compared to deceased donor kidney transplantation (DDKT) recipients. In the young and elderly, the adjusted ORs were 0.69 (95%CI, 0.52 to 0.90, p = 0.01) and 0.93 (95%CI, 0.62 to 1.39, p = 0.73) and did not differ significantly from each other (p-value for interaction = 0.38). In DDKT, the risk of hospital readmission is similar between recipients with donation after cardiac death (DCD) or brain death (DBD) and the risk was similar between the young and elderly.

CONCLUSION

A lower risk of post-transplant 3-month hospital readmission was found in recipients after LDKT compared to DDKT, and this benefit of LDKT might be less dominant in elderly patients. In DDKT, having either DCD or DBD donors is not associated with post-transplant 3-month hospital readmission, regardless of age. Tailored patient management is needed for recipients with DDKT and elderly KTRs.

Molecular Aspects of Volatile Anesthetic-Induced Organ Protection and Its Potential in Kidney Transplantation

Ischemia reperfusion injury (IRI) is inevitable in kidney transplantation and negatively impacts graft and patient outcome. Reperfusion takes place in the recipient and most of the injury following ischemia and reperfusion occurs during this reperfusion phase; therefore, the intra-operative period seems an attractive window of opportunity to modulate IRI and improve short- and potentially long-term graft outcome. Commonly used volatile anesthetics such as sevoflurane and isoflurane have been shown to interfere with many of the pathophysiological processes involved in the injurious cascade of IRI. Therefore, volatile anesthetic (VA) agents might be the preferred anesthetics used during the transplantation procedure. This review highlights the molecular and cellular protective points of engagement of VA shown in in vitro studies and in vivo animal experiments, and the potential translation of these results to the clinical setting of kidney transplantation.

Phase 3 trial Design of the Hepatocyte Growth Factor Mimetic ANG-3777 in Renal Transplant Recipients With Delayed Graft Function

Introduction

One-third of kidney transplantation patients experience acute kidney injury (AKI) resulting in delayed graft function (DGF), associated with increased risk of graft failure and mortality. Preclinical and phase 2 data indicate that treatment with ANG-3777 (formerly BB3), a hepatocyte growth factor (HGF) mimetic, may improve long-term kidney function and reduce health care resource use and cost, but these data require validation in a phase 3 randomized controlled trial.

Methods

The Graft Improvement Following Transplant (GIFT) trial is a multicenter, double-blind randomized controlled trial, designed to determine the efficacy and safety of ANG-3777 in renal transplantation patients showing signs of DGF. Subjects are randomized 1:1 to ANG-3777 (2 mg/kg) administered intravenously once daily for 3 consecutive days starting within 30 hours after transplantation, or to placebo.

Results

The primary endpoint is estimated glomerular filtration rate (eGFR) at 12 months. Secondary endpoints include proportion of subjects with eGFR >30 at days 30, 90, 180, and 360; proportion of subjects whose graft function is slow, delayed, or primary nonfunction; length of hospitalization; and duration of dialysis through day 30. Adverse events are assessed throughout the study.

Conclusion

GIFT will generate data that are important to advancing treatment of DGF in this medically complex population.

Abdominal Normothermic Regional Perfusion in Donation After Circulatory Death: A Systematic Review and Critical Appraisal

BACKGROUND

Abdominal normothermic regional perfusion (aNRP) for donation after circulatory death is an emerging organ preservation technique that might lead to increased organ utilization per donor by facilitating viability testing, improving transplant outcome by early reversal of ischemia, and decreasing the risk of unintentional surgical damage. The aim of the current review is to evaluate the recent literature on the added value of aNRP when compared to local standard perfusion technique.

METHODS

The Preferred Reporting Items for Systematic reviews and Meta-Analyses guideline for systematic reviews was used, and relevant literature databases were searched. Primary outcomes were organ utilization rate and patient and graft survival after 1 year. Secondary outcomes included delayed graft function, primary nonfunction, serum creatinine, and biliary complications.

RESULTS

A total of 24 articles were included in this review. The technique is unanimously reported to be feasible and safe, but the available studies are characterized by considerable heterogeneity and bias.

CONCLUSIONS

Uniform reported outcome measures are needed to draw more definitive conclusions on transplant outcomes and organ utilization. A randomized controlled trial comparing aNRP with standard procurement technique in donation after circulatory death donors would be needed to show the added value of the procedure and determine its place among modern preservation techniques.

Kidney transplantation outcomes from elderly donors after circulatory death: a comparison with elderly brain-dead donors

Background

The use of kidneys from elderly controlled donation after circulatory death (cDCD) donors has increased significantly in recent years. Concerns about outcomes achieved with these elderly cDCD kidneys have arisen. We aimed to compare outcomes from elderly cDCD kidney transplant recipients (KTrs) and elderly donation after brain death donors (DBDs) in KTrs.

Methods

We conducted a single-centre retrospective study including 87 cDCD-KTrs (46 from donors ≥65 years of age and 41 from <65 years) and 126 DBD-KTrs from donors ≥65 years of age from 2013 through 2017). Young cDCD-KTrs were used as controls. The median follow-up was 27.1 months for all cDCD-KTrs and 29.7 months for DBD-KTrs ≥65 years of age.

Results

Donors >65 years of age represented more than half of our global cDCD cohort (52.9%). KTs from elderly cDCDs had similar rates of delayed graft function, primary non-function and vascular complications compared with young cDCD-KTrs and elderly DBD-KTrs. Short and medium-term graft survival from elderly cDCD kidneys are excellent and are comparable to those from young cDCD and elderly DBD kidneys (90% young cDCD versus 88% elderly cDCD versus 80% elderly DBD at 36 months, P = 0.962 and 0.180, respectively). Although recipients from cDCDs ≥65 years of age showed lower 3-year patient survival (78% versus 87% in elderly DBD-KTrs; P = 0.01), recipient age was the only determinant of patient survival [hazard ratio 1.10 (95% confidence interval 1.02–1.17); P < 0.01], without any influence of donor characteristics.

Conclusions

The use of kidneys from elderly cDCDs is increasing in Spain. Short- and medium-term graft outcomes are similar when comparing kidneys from elderly cDCDs and DBDs. Recipient age is the only determinant of patient survival. Additional studies are needed to assess long-term outcomes.

Hypoperfusion warm ischaemia time in renal transplants from donors after circulatory death

Background

The donor hypoperfusion phase before asystole in renal transplants from donors after circulatory death (DCD) has been considered responsible for worse outcomes than those from donors after brain death (DBD).

Methods

We included 10 309 adult renal transplants (7128 DBD and 3181 DCD; 1 January 2010–31 December 2016) from the UK Transplant Registry. We divided DCD renal transplants into groups according to hypoperfusion warm ischaemia time (HWIT). We compared delayed graft function (DGF) rates, primary non-function (PNF) rates and graft survival among them using DBD renal transplants as a reference.

Results

The DGF rate was 21.7% for DBD cases, but ∼40% for DCD cases with HWIT ≤30 min (0–10 min: 42.1%, 11–20 min: 43%, 21–30 min: 38.4%) and 60% for DCD cases with HWIT &gt;30 min (P &lt; 0.001). All DCD groups showed higher DGF risk than DBD renal transplants in multivariable analysis {0–10 min: odds ratio [OR] 2.686 [95% confidence interval (CI) 2.352–3.068]; 11–20 min: OR 2.531 [95% CI 2.003–3.198]; 21–30 min: OR 1.764 [95% CI 1.017–3.059]; &gt;30 min: OR 5.814 [95% CI 2.798–12.081]}. The highest risk for DGF in DCD renal transplants with HWIT &gt;30 min was confirmed by multivariable analysis [versus DBD: OR 5.814 (95% CI 2.798–12.081) versus DCD: 0–10 min: OR 2.165 (95% CI 1.038–4.505); 11–20 min: OR 2.299 (95% CI 1.075–4.902); 21–30 min: OR 3.3 (95% CI 1.33–8.197)]. No significant differences were detected regarding PNF rates (P = 0.713) or graft survival (P = 0.757), which was confirmed by multivariable analysis.

Conclusions

HWIT &gt;30 min increases the risk for DGF greatly, but without affecting PNF or graft survival.

"Does Perioperative Patient Perfusion Obviate the Need for Kidney Machine Perfusion?" A Retrospective Analysis of Patients Receiving a Kidney From "Donation After Circulatory Death" Donors

BACKGROUND

Delayed graft function (DGF) remains a clinically relevant problem in the post-transplant period, especially in patients with a renal graft from a "donation after cardiac death" (DCD) donor. Controversy exists around the optimal perioperative fluid therapy in such patients. These patients may benefit from a perioperative saline loading fluid protocol, which may reduce the risk of DGF.

METHODS

We compared 2 cohorts of patients who underwent a renal transplantation with a graft from a DCD donor. From January 2003 until December 2012, patients (N = 46) were hemodynamically managed at the discretion of the care-giving physician, without a preoperative fluid administration protocol (first study period). From January 2015 until March 2019 (N = 26), patients received saline loading before, during, and after kidney transplantation according to a well-defined saline loading fluid protocol (second study period). The relationship between the use of this perioperative fluid protocol and DGF was analyzed using univariable and multivariable logistic regression models.

RESULTS

DGF occurred in 11 of 46 (24%) patients in the first study period and in 1 of 26 (4%) in the second study period (P < .05). In a multivariable model, correcting for cold ischemia time and Kidney Donor Risk Index, the use of a saline loading fluid protocol in the perioperative phase was nearly significantly associated with a decrease in DGF (P = .07).

CONCLUSION

In our DCD transplant population, DGF rates were low. Our data further strongly suggest that implementation of a perioperative saline loading fluid protocol was independently associated with a lower risk of DGF.

Donor Age, Cold Ischemia Time, and Delayed Graft Function

BACKGROUND AND OBJECTIVES

Increased donor age is one of the most important risk factors for delayed graft function (DGF), and previous studies suggest that the harmful effect of cold ischemia time is increased in kidneys from older donors. Our aim was to study the association of increased donor age and cold ischemia time with the risk of delayed graft function in a large cohort kidney transplants from the current era.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Scientific Registry of Transplant Recipients was used for this observational, retrospective registry analysis to identify all deceased donor kidney transplantations in the United States between 2010 and September 2018, who were on dialysis pretransplantation (n=90,810). The association of donor age and cold ischemia time with the risk of DGF was analyzed in multivariable models adjusted for recipient characteristics (age, race, sex, diabetes, calculated panel-reactive antibodies, pretransplant dialysis duration) and donor characteristics (cause of death, sex, race, body mass index, creatinine, donation after circulatory death status, history of hypertension, and HLA mismatch).

RESULTS

Cold ischemia time and donor age were independently associated with the risk of DGF, but the risk of DGF was not statistically significantly lower in donor age categories between 50 and 64 years, compared with donors ≥65 years. The harmful association of cold ischemia time was not higher in kidneys from older donors in any age category, not even among donation after circulatory death donors. When donor risk was assessed with kidney donor profile index, although a statistically significant interaction with cold ischemia time was found, no practically meaningful increase in cold-ischemia susceptibility of kidneys with a high kidney donor profile index was found.

CONCLUSIONS

We were unable to demonstrate an association between donor age and DGF. The association of longer cold ischemia time with the risk of DGF was not magnified in older or more marginal donors.

Contemporary patterns in kidney graft survival from donors after circulatory death in the United States

BACKGROUND

Kidney transplants from donors after circulatory death (DCD) make up an increasing proportion of all deceased donor kidney transplants in the United States (US). However, DCD grafts are considered to be of lower quality than kidneys from donors after brain death (DBD). It is unclear whether graft survival is different for these two types of donor kidneys.

MATERIALS AND METHODS

We conducted a retrospective cohort study of US deceased donor kidney recipients using data from the United Network of Organ Sharing from 12/4/2014 to 6/30/2018. We employed a Cox proportional hazard model with mixed effects to compare all-cause graft loss and death-censored graft loss for DCD versus DBD deceased donor kidney transplant recipients. We used transplant center as the random effects term to account for cluster-specific random effects. In the multivariable analysis, we adjusted for recipient characteristics, donor factors, and transplant logistics.

RESULTS

Our cohort included 27,494 DBD and 7,770 DCD graft recipients transplanted from 2014 to 2018 who were followed over a median of 1.92 years (IQR 1.08-2.83). For DCD compared with DBD recipients, we did not find a significant difference in all-cause graft loss (hazard ratio [HR] 0.96, 95% confidence interval [CI] 0.87-1.05 in univariable and HR 1.03 [95% CI 0.95-1.13] in multivariable analysis) or for death-censored graft loss (HR 0.97 (95% CI 0.91-1.06) in univariable and 1.05 (95% CI 0.99-1.11) in multivariable analysis).

CONCLUSIONS

For a contemporary cohort of deceased donor kidney transplant recipients, we did not find a difference in the likelihood of graft loss for DCD compared with DBD grafts. These findings signal a need for additional investigation into whether DCD status independently contributes to other important outcomes for current kidney transplant recipients and indices of graft quality.

Transplanting kidneys from donation after cardiac death donors with acute kidney injury

Donation after cardiac death (DCD) and acute kidney injury (AKI) donors have historically been considered independent risk factors for delayed graft function (DGF), allograft failure, and inferior outcomes. With growing experience, updated analyses have shown good outcomes. There continues to be limited data, however, on outcomes specific to DCD donors who have AKI. Primary outcomes for this study were post-kidney transplant patient and allograft survival comparing two donor groups: DCD AKIN stage 2-3 and DBD AKIN stage 2-3. In comparing these groups, there were no short- or long-term differences in patient (hazard ratio [HR] 1.07, 95% confidence interval [CI] 0.54-1.93, P = .83) or allograft survival (HR 1.47, 95% CI 0.64-2.97, P = .32). In multivariate models, the DCD/DBD status had no significant impact on the estimated GFR (eGFR) at 1 (P = .38), 2 (P = .60), and 3 years (P = .52). DGF (57.9% vs 67.9%, P = .09), rejection (12.1% vs 13.9%, P = .12), and progression of interstitial fibrosis/tubular atrophy (IFTA) on protocol biopsy (P = .16) were similar between the two groups. With careful selection, good outcomes can be achieved utilizing severe AKI DCD kidneys. Historic concerns regarding primary nonfunction, DGF resulting in interstitial fibrosis and rejection, and inferior outcomes were not observed. Given the ongoing organ shortage, increased effort should be undertaken to further utilize these donors.

Utility and safety of early allograft biopsy in adult deceased donor kidney transplant recipients

INTRODUCTION

Delayed graft function (DGF) is considered a risk factor for rejection after kidney transplantation (KTx). Clinical guidelines recommend weekly allograft biopsy until DGF resolves. However, who may benefit the most from such an aggressive policy and when histology should be evaluated remain debated.

METHODS

We analyzed 223 biopsies in 145 deceased donor KTx treated with basiliximab or anti-thymocyte globulin (rATG) and calcineurin inhibitor-based maintenance. The aim of the study was to assess the utility and safety of biopsies performed within 28 days of transplant. Relationships between transplant characteristics, indication, timing, and biopsy-related outcomes were evaluated.

RESULTS

Main indication for biopsy was DGF (87.8%) followed by lack of improvement in graft function (9.2%), and worsening graft function (3.1%). Acute tubular necrosis was the leading diagnosis (89.8%) whereas rejection was detected in 8.2% specimens. Rejection was more frequent in patients biopsied due to worsening graft function or lack of improvement in graft function than DGF (66.7% vs. 3.5%; P = 0.0075 and 33.3% vs. 3.5%; P = 0.0104, respectively) and in biopsies performed between day 15 and 28 than from day 0 to 14 (31.2% vs. 3.7%; P = 0.0002). Complication rate was 4.1%. Management was affected by the information gained with histology in 12.2% cases (7% considering DGF).

CONCLUSIONS

In low-immunological risk recipients treated with induction and calcineurin inhibitors maintenance, protocol biopsies obtained within 2 weeks of surgery to rule out rejection during DGF do not necessarily offer a favourable balance between risks and benefits. In these patients, a tailored approach may minimize complications thus optimizing results.

Donation after cardiac death kidneys are suitable for pediatric recipients

Despite the high number of children listed for kidney transplantation and shortage of deceased organ donors, there is reluctance to utilize DCD kidneys in pediatric recipients. We examined outcomes in pediatric kidney transplant patients who received a DCD kidney allograft. UNOS database was queried to examine outcomes in all pediatric kidney transplant recipients from 1994 to 2017. Pediatric status was defined as <18 years at the time of transplantation. Recipients were divided by DBD or DCD allograft status. Donor and recipient demographic data were examined. Patient and allograft survival was calculated, and Kaplan-Meier survival curves were generated. A P-value of <0.05 was considered to be significant. A total of 286 pediatric kidney transplant recipients received a DCD allograft. The donors in the DCD group were significantly younger than those in the DBD group (21.7 vs 23.3 years), with a higher KDPI (26.5% vs 22.9%). In the DCD group, the average age at transplant was younger (11.6 vs 12.9 years), with no difference in cold ischemia time or length of stay between the two groups. Rates of delayed graft function were higher in the DCD group, but despite this, there were no significant differences in allograft or patient survival between the groups. There is no difference in allograft survival in pediatric kidney transplant recipients who receive a DCD kidney allograft. DCD kidney allografts are suitable for transplantation in pediatric patients and can greatly expand the donor pool.

Intraoperative Fluid Restriction is Associated with Functional Delayed Graft Function in Living Donor Kidney Transplantation: A Retrospective Cohort Analysis

Background: In 2016 we observed a marked increase in functional delayed graft function (fDGF) in our living donor kidney transplantation (LDKT) recipients from 8.5% in 2014 and 8.8% in 2015 to 23.0% in 2016. This increase coincided with the introduction of a goal-directed fluid therapy (GDFT) protocol in our kidney transplant recipients. Hereupon, we changed our intraoperative fluid regimen to a fixed amount of 50 mL/kg body weight (BW) and questioned whether the intraoperative fluid regimen was related to this increase in fDGF. Methods: a retrospective cohort analysis of all donors and recipients in our LDKT program between January 2014–February 2017 (n = 275 pairs). Results: Univariate analysis detected various risk factors for fDGF. Dialysis dependent recipients were more likely to develop fDGF compared to pre-emptively transplanted patients (p < 0.001). Recipients developing fDGF received less intraoperative fluid (36 (25.9–50.0) mL/kg BW vs. 47 (37.3–55.6) mL/kg BW (p = 0.007)). The GDFT protocol resulted in a reduction of intraoperative fluid administration on average by 850 mL in total volume and 21% in mL/kg BW compared to our old protocol (p < 0.001). In the unadjusted analysis, a higher intraoperative fluid volume in mL/kg BW was associated with a lower risk for the developing fDGF (OR 0.967, CI (0.941–0.993)). After adjustment for the confounders, prior dialysis and the use of intraoperative noradrenaline, the relationship of fDGF with fluid volume was still apparent (OR 0.970, CI (0.943–0.998)). Conclusion: Implementation of a GDFT protocol led to reduced intraoperative fluid administration in the LDKT recipients. This intraoperative fluid restriction was associated with the development of fDGF.

Prediction models for delayed graft function: external validation on The Dutch Prospective Renal Transplantation Registry

Background

Delayed graft function (DGF) is a common complication after kidney transplantation in the era of accepting an equal number of brain- and circulatory-death donor kidneys in the Netherlands. To identify those cases with an increased risk of developing DGF, various multivariable algorithms have been proposed. The objective was to validate the reproducibility of four predictive algorithms by Irish et al. (A risk prediction model for delayed graft function in the current era of deceased donor renal transplantation. Am J Transplant 2010;10:2279-2286) (USA), Jeldres et al. (Prediction of delayed graft function after renal transplantation. Can Urol Assoc J 2009;3:377-382) (Canada), Chapal et al. (A useful scoring system for the prediction and management of delayed graft function following kidney transplantation from cadaveric donors. Kidney Int 2014;86:1130-1139) (France) and Zaza et al. (Predictive model for delayed graft function based on easily available pre-renal transplant variables. Intern Emerg Med 2015;10:135-141) (Italy) according to a novel framework for external validation.

Methods

We conducted a prospective observational study with data from the Dutch Organ Transplantation Registry (NOTR). Renal transplant recipients from all eight Dutch academic medical centers between 2002 and 2012 who received a deceased allograft were included (N = 3333). The four prediction algorithms were reconstructed from donor, recipient and transplantation data. Their predictive value for DGF was validated by c-statistics, calibration statistics and net benefit analysis. Case-mix (un)relatedness was investigated with a membership model and mean and standard deviation of the linear predictor.

Results

The prevalence of DGF was 37%. Despite a significantly different case-mix, the US algorithm by Irish was best reproducible, with a c-index of 0.761 (range 0.756 - 0.762), and well-calibrated over the complete range of predicted probabilities of having DGF. The US model had a net benefit of 0.242 at a threshold probability of 0.25, compared with 0.089 net benefit for the same threshold in the original study, equivalent to correctly identifying DGF in 24 cases per 100 patients (true positive results) without an increase in the number of false-positive results.

Conclusions

The US model by Irish et al. was generalizable and best transportable to Dutch recipients with a deceased donor kidney. The algorithm detects an increased risk of DGF after allocation and enables us to improve individual patient management.

Nationwide Outcomes after Renal Transplantation from Kidney-Only versus Multiple-Organ Deceased Donors

To assess renal transplant outcomes after donation by kidney-only (KO) versus multiple-organ (MO) donors on a national scale. The United Network for Organ Sharing database was examined for patients undergoing isolated kidney transplant from a deceased donor from 2000 through 2016. Comparison was made between recipients of grafts from KO versus MO donors at baseline and in a cohort of KO and MO recipients matched via propensity scoring. Outcomes of interest included delayed graft function (DGF), patient survival, and the cumulative incidence of graft loss. There were 33,326 recipients in the KO cohort versus 144,690 in the MO cohort. Donation after cardiac death donors were more prevalent in the KO group (43.8% vs 5.3%; P < 0.001). DGF occurred in 36.1 per cent of the KO versus 22.7 per cent of the MO recipients ( P < 0.001). Five-year survival was 79.5 per cent versus 83.4 per cent ( P < 0.001) in the KO versus MO group. After propensity matching, DGF was still more common in the KO group (33.1% vs 30.1%; P < 0.001). Patient survival was similar (79.5% KO vs 80.1% MO; P = 0.117). Cumulative incidence of graft loss was higher in the KO group (17.8% vs 16.8%). Survival outcomes from KO donors are actually quite good and should not be considered as inferior to MO donors.

Algorithms for mapping kidney tissue oxygenation during normothermic machine perfusion using hyperspectral imaging

The lack of donor grafts is a severe problem in transplantation medicine. Hence, the improved preservation of existing and the usage of organs that were deemed untransplantable is as urgent as ever. The development of novel preservation techniques has come into focus. A promising alternative to traditional cold storage is normothermic machine perfusion (NMP), which provides the benefit of improving the organs' viability and of assessing the organs' status under physiological conditions. For this purpose, methods for evaluating organ parameters have yet to be developed. In a previous study, we determined the tissue oxygen saturation (StO2) of kidneys during NMP with hyperspectral imaging (HSI) based on a discrete wavelength (DW) algorithm. The aim of the current study was to identify a more accurate algorithm for StO2 calculation. A literature search revealed three candidates to test: a DW algorithm and two full spectral algorithms - area under a curve and partial least square regression (PLSR). After obtaining suitable calibration data to train each algorithm, they were evaluated during NMP. The wavelength range from 590 to 800 nm was found to be appropriate for analyzing StO2 of kidneys during NMP. The PLSR method shows good results in analyzing the tissues' oxygen status in perfusion experiments.

Uncontrolled donation after circulatory death: A cohort study of data from a long-standing deceased-donor kidney transplantation program

Despite good long-term outcomes of kidney transplants from controlled donation after circulatory death (DCD) donors, there are few uncontrolled DCD (uDCD) programs. This longitudinal study compares outcomes for all uDCD (N = 774) and all donation after brain death (DBD) (N = 613) kidney transplants performed from 1996 to 2015 at our center. DBD transplants were divided into those from standard-criteria (SCD) (N = 366) and expanded-criteria (N = 247) brain-dead donors (ECD). One-, 5-, and 10-year graft survival rates were 91.7%, 85.7%, and 80.6% for SCD; 86.0%, 75.8%, and 61.4% for ECD; and 85.1%, 78.1%, and 72.2% for uDCD, respectively. Graft survival was worse in recipients of uDCD kidneys than of SCD (P = .004) but better than in transplants from ECD (P = .021). The main cause of graft loss in the uDCD transplants was primary nonfunction. Through logistic regression, donor death due to pulmonary embolism (OR 4.31, 95% CI 1.65-11.23), extrahospital CPR time ≥75 minutes (OR1.94, 95%CI 1.18-3.22), and in-hospital CPR time ≥50 minutes (OR 1.79, 95% CI 1.09-2.93) emerged as predictive factors of primary nonunction. According to the outcomes of our long-standing kidney transplantation program, uDCD could help expand the kidney donor pool.

Kidney transplant from uncontrolled donation after circulatory death donors maintained by nECMO has long-term outcomes comparable to standard criteria donation after brain death

Uncontrolled donation after circulatory death (uDCD) increases organ availability for kidney transplant (KT) with short-term outcomes similar to those obtained from donation after brain death (DBD) donors. However, heterogeneous results in the long term have been reported. We compared 10-year outcomes between 237 KT recipients from uDCD donors maintained by normothermic extracorporeal membrane oxygenation (nECMO) and 237 patients undergoing KT from standard criteria DBD donors during the same period at our institution. We further analyzed risk factors for death-censored graft survival in the uDCD group. Delayed graft function (DGF) was more common in the uDCD group (73.4% vs 46.4%; P < .01), although glomerular filtration rates at the end of follow-up were similar in the 2 groups. uDCD and DBD groups had similar rates for 10-year death-censored graft (82.1% vs 80.4%; P = .623) and recipient survival (86.2% vs 87.6%; P = .454). Donor age >50 years was associated with graft loss in the uDCD group (hazard ratio: 1.91; P = .058), whereas the occurrence of DGF showed no significant effect. uDCD KT under nECMO support resulted in similar graft function and long-term outcomes compared with KT from standard criteria DBD donors. Increased donor age could negatively affect graft survival after uDCD donation.

BEST Life-"Bringing ECMO Simulation To Life"-How Medical Simulation Improved a Regional ECMO Program

The implemented "ECMO for Greater Poland" program takes full advantage of the ECMO (extracorporeal membrane oxygenation) perfusion therapy to promote health for 3.5 million inhabitants in the region. The predominant subjects of implementation are patients with hypothermia, with severe reversible respiratory failure (RRF), and treatment of other critical states leading to heart failure such as sudden cardiac arrest, cardiogenic shock or acute intoxication. Finally, it promotes donation after circulatory death (DCD) strategy in selected organ donor cases. ECMO enables recovery of organs' function after unsuccessful lifesaving treatment. Because this organizational model is complex and expensive, we use advanced high-fidelity medical simulation to prepare for real-life implementation. During the first four months, we performed scenarios mimicking "ECMO for DCD," "ECMO for ECPR (extended cardiopulmonary resuscitation)," "ECMO for RRF" and "ECMO in hypothermia." It helped to create algorithms for aforementioned program arms. In the following months, three ECMO courses for five departments in Poznan (capitol city of Greater Poland) were organized and standardized operating procedures for road ECMO transportation within Medical Emergency System were created. Soon after simulation program, 38 procedures with ECMO perfusion therapy including five road transportations on ECMO were performed. The Maastricht category II DCD procedures were done four times on real patients and in two cases double successful kidney transplantations were carried out for the first time in Poland. ECMO was applied in two patients with hypothermia, nine adult patients with heart failure, and five with RRF, for the first time in the region. In the pediatric group, ECMO was applied in four patients with RRF and 14 with heart failure after cardiac surgery procedures. Additionally, one child was treated successfully following 200 km-long road transport on ECMO. We achieved good and promising results especially in VV ECMO therapy. Simulation-based training enabled us to build a successful procedural chain, and to eliminate errors at the stage of identification, notification, transportation, and providing ECMO perfusion therapy. We discovered the important role of medical simulation, not only to test the medical professional's skills, but also to promote ECMO therapy in patients with critical/life-threatening states. Moreover, it also resulted in increase of the potential organ pool from DCD in the Greater Poland region.

Impact of Donor Age on Clinical Outcomes of Primary Single Kidney Transplantation From Maastricht Category-III Donors After Circulatory Death

BACKGROUND

Standard-criteria donation after circulatory death (DCD) kidney transplants (KTx) have higher primary nonfunction, delayed graft function (DGF), and rejection rates than age-matched donation after brain death (DBD) but similar graft survival. Data on expanded-criteria DCD are conflicting and many centers remain concerned regarding their use.

METHODS

In this single-center observational study with 5-year follow-up, we analyzed data from 112 primary DCD Maastricht category-III single KTx receiving similar organ preservation and maintenance immunosuppression. Patients were sorted as young DCD (donor <60 years, 72 recipients) or old DCD (donor ≥60 years, 40 recipients). Old DCD outcomes were compared with young DCD and to a DBD control group (old DBD, donor ≥60 years, 40 recipients).

RESULTS

After 5 years, old DCD showed lower patient survival (66% vs 85%; P = 0.014), death-censored graft survival (63% vs 83%; P = 0.001), and Modification of Diet in Renal Disease estimated glomerular filtration rate (34, 27.0-42.0 mL/min per 1.73 m2 vs 45.0, 33.0-58.0 mL/min per 1.73 m2; P = 0.021) than young DCD with higher DGF (70% vs 47.2%; P = 0.029) and graft thrombosis (12.5% vs 1.4%; P = 0.021). Comparison between old DCD and old DBD showed similar 5-year patient survival (66% vs 67%; P = 0.394) and death-censored graft survival (63% vs 69%; P = 0.518) but higher DGF (70% vs 37.5%; P = 0.007) and lower estimated glomerular filtration rate (34, 27.0-42.0 mL/min per 1.73 m2 vs 41, 40.0-42.0 mL/min per 1.73 m2; P = 0.029). Multivariate Cox regression analysis showed that donor 60 years or older (hazard ratio, 3.135; 95% confidence interval, 1.716-5.729; P < 0.001) and induction with anti-IL2-receptor-α monoclonal antibody (hazard ratio, 0.503; 95% confidence interval, 0.269-0.940, P = 0.031 in favor of induction with rabbit antithymocyte globulin) are independent predictors of transplant loss.

CONCLUSIONS

Overall, single KTx from DCD Maastricht category-III donors 60 years or older have inferior outcomes than KTx from donors younger than 60 years. Comparison with age-matched DBD showed similar patient and graft survivals. However, the discrepancy in graft function between DCD and DBD deserves further investigation.

Liver Transplant Recipients With End-Stage Renal Disease Largely Benefit From Kidney Transplantation

BACKGROUND

The incidence of end-stage renal disease (ESRD) after liver transplant (LT) has increased. The actual benefit of kidney transplantation (KT) is not completely understood in LT recipients with ESRD.

METHODS

We analyzed Scientific Registry of Transplant Recipients data for all KT candidates with prior LT from 1998 to 2014; the benefits of KT relative to remaining on dialysis were compared by means of multivariate Cox proportional hazards regression analysis.

RESULTS

The number of these KT candidates with prior LT has tripled from 98 in 1998 to 323 in 2015; LT recipients with ESRD remaining on dialysis have a 2.5-times increase in the risk of liver graft failure and a 3.6-times increase in the risk of patient death compared with these patients receiving KT. The adjusted liver graft and patient survival rates after donors from donation after cardiac death or expanded-criteria donor kidney transplantation were significantly higher than in patients remaining on dialysis in LT recipients with ESRD.

CONCLUSIONS

The number of referrals to KT with prior LT is increasing at a rapid rate. Remaining on dialysis in LT recipients with ESRD has profound increased risks of liver graft failure and patient death in comparison to receiving a KT. LT recipients with ESRD can benefit from expanded-criteria donor and donation after cardiac death kidney transplantation.

The duration of asystolic ischemia determines the risk of graft failure after circulatory-dead donor kidney transplantation: A Eurotransplant cohort study

Circulatory death donor (DCD) kidney transplantations are steadily increasing. Consensus reports recommend limiting donor warm ischemia time (DWIT) in DCD donation, although an independent effect on graft outcome has not been demonstrated. We investigated death-censored graft survival in 18 065 recipients of deceased-donor kidney transplants in the Eurotransplant region: 1059 DCD and 17 006 brain-dead donor (DBD) kidney recipients. DWIT was defined as time from circulatory arrest until cold flush. DCD donation was an independent risk factor for graft failure (adjusted hazard ratio [HR] 1.28, 95% CI 1.10-1.46), due to an increased risk of primary nonfunction (62/1059 vs 560/17 006; P < .0001). With DWIT in the model, DCD donation was no longer a risk factor, demonstrating that DWIT explains the inferior graft survival of DCD kidneys. Indeed, DCD transplants with short DWIT have graft survival comparable to that of standard-criteria DBD transplants (P = .59). DWIT also associated with graft failure in DCDs (adjusted HR 1.20 per 10-minute increase, 95% CI 1.03-1.42). At 5 years after transplantation, graft failure occurred in 14 of 133 recipients (10.5%) with DWIT <10 minutes, 139 of 555 recipients (25.0%) with DWIT between 10 and 19 minutes, and 117 of 371 recipients (31.5%) with DWIT ≥20 minutes. These findings support the expert opinion-based guidelines to limit DWIT.

Allogeneic mesenchymal stem cells as induction therapy are safe and feasible in renal allografts: pilot results of a multicenter randomized controlled trial

BACKGROUND

Kidneys from deceased donors are being used to meet the growing need for grafts. However, delayed graft function (DGF) and acute rejection incidences are high, leading to adverse effects on graft outcomes. Optimal induction intervention should include both renal structure injury repair and immune response suppression. Mesenchymal stem cells (MSCs) with potent anti-inflammatory, regenerative, and immune-modulatory properties are considered a candidate to prevent DGF and acute rejection in renal transplantation. Thus, this prospective multicenter paired study aimed to assess the clinical value of allogeneic MSCs as induction therapy to prevent both DGF and acute rejection in deceased donor renal transplantation.

METHODS

Forty-two renal allograft recipients were recruited and divided into trial and control groups. The trial group (21 cases) received 2 × 10⁶/kg human umbilical-cord-derived MSCs (UC-MSCs) via the peripheral vein before renal transplantation, and 5 × 10⁶ cells via the renal artery during the surgical procedure. All recipients received standard induction therapy. Incidences of DGF and biopsy-proven acute rejection were recorded postoperatively and severe postoperative complications were assessed. Graft and recipient survivals were also evaluated.

RESULTS

Treatment with UC-MSCs achieved comparable graft and recipient survivals with non-MSC treatment (P = 0.97 and 0.15, respectively). No increase in postoperative complications, including DGF and acute rejection, were observed (incidence of DGF: 9.5% in the MSC group versus 33.3% in the non-MSC group, P = 0.13; Incidence of acute rejection: 14.3% versus 4.8%, P = 0.61). Equal postoperative estimated glomerular filtration rates were found between the two groups (P = 0.88). All patients tolerated the MSCs infusion without adverse clinical effects. Additionally, a multiprobe fluorescence in situ hybridization assay revealed that UC-MSCs administered via the renal artery were absent from the recipient's biopsy sample.

CONCLUSIONS

Umbilical-cord-derived MSCs can be used as clinically feasible and safe induction therapy. Adequate timing and frequency of UC-MSCs administration may have a significant effect on graft and recipient outcomes. Trial registration NCT02490020 . Registered on June 29 2015.

The role of extracorporeal membrane oxygenation in patients after irreversible cardiac arrest as potential organ donors

The number of people waiting for a kidney or liver transplant is growing systematically. Due to the latest advances in transplantation, persons after irreversible cardiac arrest and confirmation of death have become potential organ donors. It is estimated that they may increase the number of donations by more than 40%. However, without good organization and communication between pre-hospital care providers, emergency departments, intensive care units and transplantation units, it is almost impossible to save the organs of potential donors in good condition. Various systems, including extracorporeal membrane oxygenation (ECMO), supporting perfusion of organs for transplantation play a key role. In 2016 the "ECMO for Greater Poland" program was established. Although its main goal is to improve the survival rate of patients suffering from life-threatening cardiopulmonary conditions, one of its branches aims to increase the donation rate in patients with irreversible cardiac arrest. In this review, the role of ECMO in the latter group as the potential organ donors is presented.

Allogeneic mesenchymal stem cell as induction therapy to prevent both delayed graft function and acute rejection in deceased donor renal transplantation: study protocol for a randomized controlled trial

Background

Using kidneys from deceased donors is an available strategy to meet the growing need of grafts. However, higher incidences of delayed graft function (DGF) and acute rejection exert adverse effects on graft outcomes. Since ischemia-reperfusion injury (IRI) and ongoing process of immune response to grafts are the major causes of DGF and acute rejection, the optimal induction intervention should possess capacities of both repairing renal structure injury and suppressing immune response simultaneously. Mesenchymal stem cells (MSCs) with potent anti-inflammatory, regenerative and immune-modulatory properties are considered as a candidate to prevent both DGF and acute rejection in renal transplantation. Previous studies just focused on the safety of autologous MSCs on living-related donor renal transplants, and lack of concomitant controls and the sufficient sample size and source of MSCs. Here, we propose a prospective multicenter controlled study to assess the clinical value of allogeneic MSCs in preventing both DGF and acute rejection simultaneously as induction therapy in deceased-donor renal transplantation.

Methods/design

Renal allograft recipients (n = 100) will be recruited and divided into trial and control groups, and 50 patients in the trial group will be administered with a dose of 2 × 10⁶ per kilogram human umbilical-cord-derived MSCs (UC-MSCs) via peripheral vein injection preoperatively, and a dose of 5 × 10⁶ cells via renal arterial injection during surgery, with standard induction therapy. Incidences of postoperative DGF and biopsy-proved acute rejection (BPAR) will be recorded and analyzed. Additionally, other clinical parameters such as baseline demographics, graft and recipient survival and other severe postoperative complications, including complicated urinary tract infection, severe pneumonia, and severe bleeding, will be also assessed.

Discussion

This study will clarify the clinical value of UC-MSCs in preventing DGF and acute rejection simultaneously in deceased-donor renal transplantation, and provide evidence as to whether allogeneic MSCs can be used as clinically feasible and safe induction therapy.

Trial registration

ClinicalTrials.gov, NCT02490020. Registered on 29 June 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2291-y) contains supplementary material, which is available to authorized users.

Use and Outcomes of Kidneys from Donation after Circulatory Death Donors in the United States

Donation after circulatory death (DCD) donors are an important source of kidneys for transplantation, but DCD donor transplantation is less common in the United States than in other countries. In this study of national data obtained between 2008 and 2015, recovery of DCD kidneys varied substantially among the country's 58 donor service areas, and 25% of DCD kidneys were recovered in only four donor service areas. Overall, 20% of recovered DCD kidneys were discarded, varying from 3% to 33% among donor service areas. Compared with kidneys from neurologically brain dead (NBD) donors, DCD kidneys had a higher adjusted odds ratio of discard that varied from 1.25 (95% confidence interval [95% CI], 1.16 to 1.34) in kidneys with total donor warm ischemic time (WIT) of 10-26 minutes to 2.67 (95% CI, 2.34 to 3.04) in kidneys with total donor WIT >48 minutes. Among the 12,831 DCD kidneys transplanted, kidneys with WIT≤48 minutes had survival similar to that of NBD kidneys. DCD kidneys with WIT>48 minutes had a higher risk of allograft failure (hazard ratio, 1.23; 95% CI, 1.07 to 1.41), but this risk was limited to kidneys with cold ischemia time (CIT) >12 hours. We conclude that donor service area-level variation in the recovery and discard of DCD kidneys is large. Additional national data collection is needed to understand the potential to increase DCD donor transplantation in the United States. Strategies to minimize cold ischemic injury may safely allow increased use of DCD kidneys with WIT>48 minutes.

Vasa recta pericyte density is negatively associated with vascular congestion in the renal medulla following ischemia reperfusion in rats

Recent evidence suggests that a greater density of pericytes in renal cadaveric allografts is associated with better recovery following transplant. The physiological mechanism(s) through which pericyte density may be beneficial is not well understood. The goal of this study was to test the hypothesis that lower medullary pericyte density is associated with greater renal injury following ischemia reperfusion (IR) in a rat model, providing a basis for future studies to better understand pericytes in a pathological environment. To test our hypothesis, we determined the association between medullary pericyte density and renal injury in spontaneously hypertensive rats (SHR) following 45 min of warm bilateral IR. We found that there was a significant negative relationship between pericyte density and plasma creatinine (slope = -0.03, P = 0.02) and blood urea nitrogen (slope = -0.5, P = 0.01) in female but not male SHR. Pericyte density was negatively associated with medullary peritubular capillary (PT) congestion in both sexes following IR (male: slope = -0.04, P = 0.009; female: slope = -0.03, P = 0.0001). To further test this relationship, we used a previously reported method to reduce pericyte density in SHR. Medullary erythrocyte congestion in vasa recta (VR) and PT significantly increased following IR in both sexes when pericyte density was pharmacologically decreased (VR: P = 0.03; PT: P = 0.03). Our data support the hypothesis that pericyte density is negatively associated with the development of IR injury in SHR, which may be mediated by erythrocyte congestion in the medullary vasculature.

Posttransplant Outcomes of Kidneys Donated After Brain Death Followed by Circulatory Death: A Cohort Study of 128 Chinese Patients

Background

Donation after brain death followed by circulatory death (DBCD) is a new class in the unique Chinese donor classification system. Currently, in China, the organ transplantation of DBCD is rising. However, there is a dearth of research on the characteristics and outcomes of DBCD kidney transplantation.

Method

We collected 128 DBCD renal transplant patients who underwent surgery between June 2013 and May 2016 at our center to analyze clinical outcomes and to share our experience to enhance perioperative management in DBCD kidney transplantation.

Results

At the end of follow-up, no patients experienced primary nonfunction, but delayed graft function occurred in 25.8%. One- and 3-year graft survivals were 97.7% and 94.5%, respectively. The average length of stay was 20.88 ± 14.6 days, the incidence of posttransplant complications was 46.1% (59 patients), and 31 patients suffered more than 1 complication. In addition, the average length of stay of patients without complications and with at least 1 complication was 13.07 ± 2.01 days and 30.02 ± 17.4 days, respectively. There was a significantly higher incidence of complications associated with the postoperative hospital stay in DBCD patients.

Conclusions

Patients who received a DBCD kidney demonstrated a good outcome in terms of both graft survival and graft function. Hence, DBCD is suitable for national reality and conditions and offers a feasible option for deceased-donor kidney transplantation in China. To prevent complications and reduce the duration of hospital stay, we should strengthen preoperative and postoperative management.

Hydrogen sulfide prevents renal ischemia-reperfusion injury in CLAWN miniature swine

BACKGROUND

Hydrogen sulfide (H₂S) has recently been reported to demonstrate both antiinflammatory and cytoprotective effects; however, its efficacy has not been well documented in large animal models. In this study, we examined whether the administration of H₂S offers cytoprotective effects on renal ischemia-reperfusion injury (IRI) in a preclinical miniature swine model.

METHODS

Major histocompatibility complex-inbred, CLAWN miniature swine (n = 9) underwent a right nephrectomy, followed by induction of a 120-min period of warm ischemia via placement of clamps on the left renal artery and vein. Group 1 (n = 3) underwent renal ischemia without H₂S administration. Groups 2 (n = 3) and 3 (n = 3) received Na₂S (prodrug of H₂S) 10 min before reperfusion of the ischemic kidneys followed by a 30-min of Na₂S postreperfusion intravenously (group 2) or selective administration of Na₂S via the left renal artery (group 3). IRI was assessed by kidney biopsies, levels of inflammatory cytokines in sera and kidney tissue.

RESULTS

Animals in group 1 had significantly higher serum creatinine levels compared with animals in groups 2 and 3 (P < 0.01). Histology showed severe tubular damage with TUNEL-positive cells in group 1 on postoperative day 2 compared with mild damage in group 2 and minimal damage in group 3. Furthermore, levels of inflammatory cytokines in both serum (interleukin-6 [IL-6], tumor necrosis factor-α, and high-mobility group box 1) and renal tissue (IL-1 and IL-6) in group 3 were markedly lower than in group 2, suggesting beneficial effects of selective Na₂S administration.

CONCLUSIONS

Na₂S administration, especially via an organ selective approach, appears to potentially offer cytoprotective and antiinflammatory effects following renal IRI.

Outcomes for primary kidney transplantation from donation after Citizens' death in China: a single center experience of 367 cases

BACKGROUND

The cases of donation after brain death followed by circulatory death (DBCD) and donation after cardiac death (DCD) have been increased year by year in China. Further research is needed to understand in the outcomes and risk factors of delayed graft function (DGF) in order to minimize the risk of DGF and ameliorate its potential impact on long-term outcomes. This study was to explore the differences in outcomes between DBCD and DCD transplant and the main risk factors for DGF in DBCD.

METHODS

Retrospective analysis of the clinical data of 367donations after citizens' death kidney transplant procedures (donors and recipients) between July 2012 and August 2015 at our center.

RESULTS

During the study period, the donation success rate was 25.3%. 164 cases of DBCD and 35 cases of DCD had been implemented and 367 kidneys were transplanted. The incidence of DGF in DBCD group were significantly lower than that of DCD group (12.0% vs. 27.0%, p = 0.002). The 1-year percent freedom from acute rejection (AR) was significantly higher in DBCD group compared with it of DCD group (94% vs. 82%, p = 0.036). Multivariate logistic regression analysis of the kidney transplants revealed that the high risk factors for DGF after renal transplantation in DBCD were history of hypertension (Odds Ratio [OR] = 5.88, 95% CI: 1.90 to 18.2, p = 0.002), low blood pressure (BP < 80 mmHg) (OR = 4.86, 95% CI: 1.58 to 14.9, p = 0.006) and serum creatinine of donor (OR = 1.09, 95% CI: 1.03 to 1.16, p = 0.003) before donation.

CONCLUSIONS

The outcomes of DBCD could be better than DCD in DGF and AR. The main risk factors for DGF in DBCD kidney transplants are donors with a history of hypertension, low blood pressure, and serum creatinine of donor before donation.

Remote Ischemic Conditioning on Recipients of Deceased Renal Transplants Does Not Improve Early Graft Function: A Multicenter Randomized, Controlled Clinical Trial

Delayed graft function is a frequent complication following deceased donor renal transplantation, and is closely related to ischemia-reperfusion injury. Experimental and clinical studies have shown protection by remote ischemic conditioning (RIC). We hypothesized that recipient RIC before kidney graft reperfusion reduces the time to graft recovery. This multicenter, blinded, randomized, controlled clinical trial included 225 adult recipients of renal transplants from deceased donors at four transplantation centers in Denmark, Sweden, and the Netherlands. Participants were randomized 1:1 to RIC or sham-RIC. RIC consisted of 4 × 5-min thigh occlusion by an inflatable tourniquet each followed by 5-min deflation, performed during surgery prior to graft reperfusion. The tourniquet remained deflated for sham-RIC. The primary endpoint was the estimated time to a 50% decrease in baseline plasma creatinine (tCr50) calculated from plasma creatinine measurements 30 days posttransplant or 30 days after the last, posttransplant dialysis. No significant differences were observed between RIC and sham-RIC-treated patients in the primary outcome median tCr50 (122 h [95% confidence interval [CI] 98-151] vs. 112 h [95% CI 91-139], p = 0.58), or the number of patients receiving dialysis in the first posttransplant week (33% vs. 35%, p = 0.71). Recipient RIC does not reduce the time to graft recovery in kidney transplantation from deceased donors. ClinicalTrials.gov: NCT01395719.

Local Expansion of Donation After Circulatory Death Kidney Transplant Activity Improves Waitlisted Outcomes and Addresses Inequities of Access to Transplantation

In the United Kingdom, donation after circulatory death (DCD) kidney transplant activity has increased rapidly, but marked regional variation persists. We report how increased DCD kidney transplant activity influenced waitlisted outcomes for a single center. Between 2002-2003 and 2011-2012, 430 (54%) DCD and 361 (46%) donation after brain death (DBD) kidney-only transplants were performed at the Cambridge Transplant Centre, with a higher proportion of DCD donors fulfilling expanded criteria status (41% DCD vs. 32% DBD; p = 0.01). Compared with U.K. outcomes, for which the proportion of DCD:DBD kidney transplants performed is lower (25%; p < 0.0001), listed patients at our center waited less time for transplantation (645 vs. 1045 days; p < 0.0001), and our center had higher transplantation rates and lower numbers of waiting list deaths. This was most apparent for older patients (aged >65 years; waiting time 730 vs. 1357 days nationally; p < 0.001), who received predominantly DCD kidneys from older donors (mean donor age 64 years), whereas younger recipients received equal proportions of living donor, DBD and DCD kidney transplants. Death-censored kidney graft survival was nevertheless comparable for younger and older recipients, although transplantation conferred a survival benefit from listing for only younger recipients. Local expansion in DCD kidney transplant activity improves survival outcomes for younger patients and addresses inequity of access to transplantation for older recipients.

Protocol of a randomised controlled, open-label trial of ex vivo normothermic perfusion versus static cold storage in donation after circulatory death renal transplantation

INTRODUCTION

Ex vivo normothermic perfusion (EVNP) is a novel technique that reconditions the kidney and restores renal function prior to transplantation. Phase I data from a series of EVNP in extended criteria donor kidneys have established the safety and feasibility of the technique in clinical practice.

METHODS AND ANALYSIS

This is a UK-based phase II multicentre randomised controlled trial to assess the efficacy of EVNP compared with the conventional static cold storage technique in donation after circulatory death (DCD) kidney transplantation. 400 patients receiving a kidney from a DCD donor (categories III and IV, controlled) will be recruited into the study. On arrival at the transplant centre, kidneys will be randomised to receive either EVNP (n=200) or remain in static cold storage (n=200). Kidneys undergoing EVNP will be perfused with an oxygenated packed red cell solution at near body temperature for 60 min prior to transplantation. The primary outcome measure will be determined by rates of delayed graft function (DGF) defined as the need for dialysis in the first week post-transplant. Secondary outcome measures include incidences of primary non-function, the duration of DGF, functional DGF defined as <10% fall in serum creatinine for 3 consecutive days in the first week post-transplant, creatinine reduction ratio days 2 and 5, length of hospital stay, rates of biopsy-proven acute rejection, serum creatinine and estimated glomerular filtration rate at 1, 3, 6 and 12 months post-transplant and patient and allograft survival. The EVNP assessment score will be recorded and the level of fibrosis and inflammation will also be measured using tissue, blood and urine samples. Ethics and dissemination. The study has been approved by the National Health Service (NHS) Health Research Authority Research Ethics Committee. The results are expected to be published in 2020.

TRIAL REGISTRATION NUMBER

ISRCTN15821205; Pre-results.

Banff Histopathological Consensus Criteria for Preimplantation Kidney Biopsies

The Banff working group on preimplantation biopsy was established to develop consensus criteria (best practice guidelines) for the interpretation of preimplantation kidney biopsies. Digitally scanned slides were used (i) to evaluate interobserver variability of histopathologic findings, comparing frozen sections with formalin-fixed, paraffin-embedded tissue of wedge and needle core biopsies, and (ii) to correlate consensus histopathologic findings with graft outcome in a cohort of biopsies from international medical centers. Intraclass correlations (ICCs) and univariable and multivariable statistical analyses were performed. Good to fair reproducibility was observed in semiquantitative scores for percentage of glomerulosclerosis, arterial intimal fibrosis and interstitial fibrosis on frozen wedge biopsies. Evaluation of frozen wedge and core biopsies was comparable for number of glomeruli, but needle biopsies showed worse ICCs for glomerulosclerosis, interstitial fibrosis and tubular atrophy. A consensus evaluation form is provided to help standardize the reporting of histopathologic lesions in donor biopsies. It should be recognized that histologic parameters may not correlate with graft outcome in studies based on organs deemed to be acceptable after careful clinical assessment. Significant limitations remain in the assessment of implantation biopsies.

Stretching the Limits of Renal Transplantation in Elderly Recipients of Grafts from Elderly Deceased Donors

An increasing number of elderly patients (≥65 years) receive a donor kidney from elderly donors after brain death (DBD) or after circulatory death (DCD). These organs are allocated within the Eurotransplant Senior Program, but outcomes must be evaluated. From the Dutch Organ Transplantation Registry, we selected 3597 recipients (≥18 years) who received a first DBD or DCD kidney during 2002-2012, and categorized them as young or elderly recipients receiving a graft from either a young or elderly donor, stratified by donor type. In multiple logistic regression analysis, elderly recipients of elderly DCD kidneys experienced more delayed graft function and acute rejection than did elderly recipients of young DBD kidneys (odds ratios 10.43 [95% confidence interval (95% CI), 5.75 to 18.91] and 2.78 [95% CI, 1.35 to 5.73], respectively). In Cox regression analysis, elderly recipients of elderly DCD kidneys had a 5-year mortality risk higher than that of elderly recipients of young DBD kidneys (hazard ratio, 1.86; 95% CI, 1.15 to 3.02). Elderly recipients of elderly kidneys had a 5-year mortality rate comparable to that of waitlisted elderly patients remaining on dialysis. Among elderly recipients, 63.8% of those who received elderly DCD kidneys, 45.5% of those who received elderly DBD kidneys, and approximately 26% of those who received young DBD or DCD kidneys had an eGFR<30 ml/min per 1.73 m² (including primary nonfunction) after 1 year. In conclusion, improving donor selection and preservation is warranted if the allocation of elderly DCD grafts to elderly recipients is to be expanded.