Mortality after Renal Allograft Failure and Return to Dialysis

Supportive care in transplantation: A patient-centered care model to better support kidney transplant candidates and recipients

Kidney transplantation (KT), although the best treatment option for eligible patients, entails maintaining and adhering to a life-long treatment regimen of medications, lifestyle changes, self-care, and appointments. Many patients experience uncertain outcome trajectories increasing their vulnerability and symptom burden and generating complex care needs. Even when transplants are successful, for some patients the adjustment to life post-transplant can be challenging and psychological difficulties, economic challenges and social isolation have been reported. About 50% of patients lose their transplant within 10 years and must return to dialysis or pursue another transplant or conservative care. This paper documents the complicated journey patients undertake before and after KT and outlines some initiatives aimed at improving patient-centered care in transplantation. A more cohesive approach to care that borrows its philosophical approach from the established field of supportive oncology may improve patient experiences and outcomes. We propose the "supportive care in transplantation" care model to operationalize a patient-centered approach in transplantation. This model can build on other ongoing initiatives of other scholars and researchers and can help advance patient-centered care through the entire care continuum of kidney transplant recipients and candidates. Multi-dimensionality, multi-disciplinarity and evidence-based approaches are proposed as other key tenets of this care model. We conclude by proposing the potential advantages of this approach to patients and healthcare systems.

Outcomes of kidney replacement therapies after kidney transplant failure: A systematic review and meta-analysis

BACKGROUND

Following kidney transplant failure, patients generally have three kidney replacement therapy (KRT) options: peritoneal dialysis (PD), haemodialysis (HD), or pre-emptive kidney re-transplantation. This review aims to explore KRT options after kidney transplant failure and compare clinical outcomes.

METHOD

This review included studies from five databases: Medline, PubMed, Embase, Cochrane, and CINAHL. The study protocol was registered at PROSPERO [CRD42024514346]. Causes of kidney transplant failure were explored. Survival and re-transplantation rates among three groups after kidney transplant failure were compared: patients starting PD (TX-PD group), patients starting HD (TX-HD group), and patients re-transplanted without bridging dialysis (TX-TX group). Causes of death were also explored. The quality of the included studies was assessed using the CASP checklist and the meta-analysis was assessed using the GRADE approach.

RESULTS

Of 6405 articles, eight articles were included in the systematic review. Chronic damage was identified as the primary cause of kidney transplant failure. The TX-TX group had a lower mortality rate than the TX-HD group and TX-PD group, though this difference was only statistically significant in comparison to the TX-HD group (OR: 2.57; 95 % CI:1.58, 4.17; I2 = 79 %; P = 0.0001). Additionally, the TX-PD group had a significantly lower mortality rate (OR: 0.83; 95 % CI:0.76, 0.90; I2 = 88 %; P < 0.0001) and higher re-transplantation rate (OR: 1.56; 95 % CI:1.41, 1.73; I2 = 0 %; P < 0.00001) compared to the TX-HD group. Cardiovascular disease, infection, and cancer were the leading causes of death.

CONCLUSION

The TX-TX group had better survival than the TX-HD group. Survival and re-transplantation rates were higher in the TX-PD group than the TX-HD group. However, age and comorbidities may impact survival and re-transplantation rates between the TX-PD and TX-HD groups, which should be explored further.

Losing Much More Than a Transplant: A Qualitative Study of Kidney Transplant Recipients' Experiences of Graft Failure

Introduction

Kidney transplant recipients with graft failure are a growing cohort of patients who experience high morbidity and mortality. Limited evidence guides their care delivery and patient perspective to improve care processes is lacking. We conducted an in-depth exploration of how individuals experience graft failure, and the specific research question was: "What impact does the loss of an allograft have on their lives?"

Methods

We adopted an interpretive descriptive methodological design. Semistructured in-depth narrative interviews were conducted with adult recipients who had a history of ≥1 graft failure. Data were collected until data saturation was achieved and analyzed using an inductive and thematic approach.

Results

Our study included 23 participants from 6 provinces of Canada. The majority were on dialysis and not waitlisted for retransplantation (60.9%). Our thematic analysis identified that the lives of participants were impacted by a range of tangible and experiential losses that go beyond the loss of the transplant itself. The themes identified include loss of control, loss of coherence, loss of certainty, loss of hope, loss of quality of life, and loss of the transplant team. Although many perceived that graft failure was inevitable, the majority were unprepared. The confusion about eligibility for retransplantation appears to contribute to these experiences.

Conclusion

Individuals with graft failure experience complex mental and emotional challenges which may contribute to poor outcomes. The number of patients with graft failure globally is increasing and our findings can help guide practices aimed at supporting and guiding them toward self-management and adaptive coping.

Haemodialysis access profile in failed kidney transplant patients: Analysis of data from the Catalan Renal Registry (1998-2016)

BACKGROUND

Data about vascular access (VA) use in failed kidney transplant (KT) patients returning to haemodialysis (HD) are limited. We analysed the VA profile of these patients, the factors associated with the likelihood of HD re-initiation through fistula (AVF) and the effect of VA in use at the time of KT on kidney graft (KTx) outcome.

METHOD

Data from the Catalan Registry on failed KT patients restarting HD and incident HD patients with native kidney failure were examined over an 18-year period.

RESULTS

The VA profile of 675 failed KT patients at HD re-initiation compared with that before KT and with 16,731 incident patients starting HD was (%): AVF 79.3 versus 88.6 and 46.2 (p = 0.001 and p < 0.001), graft AVG 4.4 versus 2.6 and 1.1 (p = 0.08 and p < 0.001), tunnelled catheter TCC 12.4 versus 5.5 and 18.0 (p = 0.001 and p < 0.001) and non-tunnelled catheter 3.9 versus 3.3 and 34.7 (p = 0.56 and p < 0.001). The likelihood of HD re-initiation by AVF was significantly lower in patients with cardiovascular disease, KT duration >5 years, dialysed through AVG or TCC before KT, and females. The analysis of Kaplan-Meier curves showed a greater KTx survival in patients dialysed through arteriovenous access than in patients using catheter just before KT (λ2 = 5.59, p = 0.0181, log-rank test). Cox regression analysis showed that patients on HD through arteriovenous access at the time of KT had lower probability of KTx loss compared to those with catheter (hazard ratio 0.71, 95% CI 0.55-0.90, p = 0.005).

CONCLUSIONS

The VA profile of failed KT patients returning to HD and incident patients starting HD was different. Compared to before KT, the proportion of failed KT patients restarting HD with AVF decreased significantly at the expense of TCC. Patients on HD through arteriovenous access at the time of KT showed greater KTx survival compared with those using catheter.

Management of an aneurysmal arteriovenous fistula in kidney transplant recipients

Aneurysms remain the most common complication of an arteriovenous fistula created for dialysis access. The management of an aneurysmal arteriovenous fistula (AAVF) in kidney transplant recipients remains contentious with a lack of clear clinical guidelines. Recipients of a functioning graft do not require the fistula for dialysis access, however risk of graft failure and needing the access at a future date must be considered. In this review we outline the current evidence in the assessment and management of a transplant recipient with an AAVF. We will describe our recommended five-step approach to assessing an AAVF in transplant patients; 1.) Define AAVF 2.) Risk assess AAVF 3.) Assess transplant graft function and future graft failure risk 4.) Consider future renal replacement therapy options 5.) Vascular mapping to assess future vascular access options. Then we will describe the current therapeutic options and when they would most appropriately be employed.

Challenges in the management of the kidney allograft: from decline to failure: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

In March 2022, Kidney Disease: Improving Global Outcomes (KDIGO) held a virtual Controversies Conference to address the important but rarely examined phase during which the kidney transplant is failing or has failed. In addition to discussing the definition of a failing allograft, 4 broad areas were considered in the context of a declining functioning graft: prognosis and kidney failure trajectory; immunosuppression strategies; management of medical and psychological complications, and patient factors; and choice of kidney replacement therapy or supportive care following graft loss. Identifying and paying special attention to individuals with failing allografts was felt to be important in order to prepare patients psychologically, manage immunosuppression, address complications, prepare for dialysis and/or retransplantation, and transition to supportive care. Accurate prognostication tools, although not yet widely available, were embraced as necessary to define allograft survival trajectories and the likelihood of allograft failure. The decision of whether to withdraw or continue immunosuppression after allograft failure was deemed to be based most appropriately on risk-benefit analysis and likelihood of retransplantation within a few months. Psychological preparation and support was identified as a critical factor in patient adjustment to graft failure, as was early communication. Several models of care were noted that enabled a medically supportive transition back to dialysis or retransplantation. Emphasis was placed on the importance of dialysis-access readiness before initiation of dialysis, in order to avoid use of central venous catheters. The centrality of the patient to all management decisions and discussions was deemed to be paramount. Patient "activation," which can be defined as engaged agency, was seen as the most effective way to achieve success. Unresolved controversies, gaps in knowledge, and areas for research were also stressed in the conference deliberations.

The Role of Allograft Nephrectomy in the Failing Kidney Transplant

Patients with failed renal allografts have associated increased morbidity and mortality. The individualization of immunosuppression taper is the key element in managing these patients to avoid graft intolerance and sensitization while balancing the risk of continued immunosuppression. Most patients with uncomplicated chronic allograft failure do not require allograft nephrectomy (AN), and there is no clear evidence that it improves outcomes. The AN procedure is associated with variable morbidity and mortality. It is reserved mainly for early technical graft failure or in symptomatic cases associated with allograft infection, malignancy, or graft intolerance syndrome. It may also be considered in those who cannot tolerate immunosuppression and are at high risk for graft intolerance. AN has been associated with an increased risk of sensitization due to inflammatory response from surgery, immunosuppression withdrawal with allograft failure, and retained endovascular tissue. Although it is presumed that for-cause AN after transplant failure is associated with sensitization, it remains unclear whether elective AN in patients who remain on immunotherapy may prevent sensitization. The current practice of immunosuppression taper has not been shown to prevent sensitization or increase infection risk, but current literature is limited by selection bias and the absence of medication adherence data. We discuss the management of failed allografts based on retransplant candidacy, wait times, risk of graft intolerance syndrome, and immunosuppression side effects. Many unanswered questions remain, and future prospective randomized trials are needed to help guide evidence-based management.

Dialysis after kidney transplant failure: how to deal with this daunting task?

The best treatment for patients with end-stage kidney disease is kidney transplantation, which, if successful provides both a reduction in mortality and a better quality of life compared to dialysis. Although there has been significant improvement in short-term outcomes after kidney transplantation, long-term graft survival still remains insufficient. As a result, there has been an increase in the number of individuals who need dialysis again after kidney transplant failure, and increasingly contribute to kidney transplant waiting lists. Starting dialysis after graft failure is a difficult task not only for the patients, but also for the nephrologists and the care team. Furthermore, recommendations for management of dialysis after kidney graft loss are lacking. Aim of this narrative review is to provide a perspective on the role of dialysis in the management of patients with failed kidney allograft. Although numerous studies have reported higher mortality in patients undergoing dialysis following kidney allograft failure, reports are contrasting. A patient-centered, individualized approach should drive the choices of initiating dialysis, dialysis modality, maintenance of immunosuppressive drugs and vascular access.

The Perspectives of General Nephrologists Toward Transitions of Care and Management of Failing Kidney Transplants

The management of failing kidney allograft and transition of care to general nephrologists (GN) remain a complex process. The Kidney Pancreas Community of Practice (KPCOP) Failing Allograft Workgroup designed and distributed a survey to GN between May and September 2021. Participants were invited via mail and email invitations. There were 103 respondents with primarily adult nephrology practices, of whom 41% had an academic affiliation. More than 60% reported listing for a second kidney as the most important concern in caring for patients with a failing allograft, followed by immunosuppression management (46%) and risk of mortality (38%), while resistant anemia was considered less of a concern. For the initial approach to immunosuppression reduction, 60% stop antimetabolites first, and 26% defer to the transplant nephrologist. Communicating with transplant centers about immunosuppression cessation was reported to occur always by 60%, and sometimes by 29%, while 12% reported making the decision independently. Nephrologists with academic appointments communicate with transplant providers more than private nephrologists (74% vs. 49%, p = 0.015). There are heterogeneous approaches to the care of patients with a failing allograft. Efforts to strengthen transitions of care and to develop practical practice guidelines are needed to improve the outcomes of this vulnerable population.

Perspectives and experiences of kidney transplant recipients with graft failure: A systematic review and meta-synthesis

BACKGROUND

Kidney transplant recipients with graft failure are a rapidly rising cohort of patients who experience high morbidity, mortality, and fragmented transitions of care between transplant and dialysis teams. Current approaches to improving care focus on medical and surgical interventions, increasing re-transplantation, and improving coordination between treating teams with little understanding of patient needs and perspectives.

METHODS

We undertook a systematic literature review of personal experiences of patients with graft failure. Six electronic and five grey literature databases were searched systematically. Of 4664 records screened 43 met the inclusion criteria. Six empirical qualitative studies and case studies were included in the final analysis. Thematic synthesis was used to combine data that included the perspectives of 31 patients with graft failure and 9 caregivers.

RESULTS

Using the Transition Model, we isolated three interconnected phases as patients transition through graft failure: shattering of lifestyle and plans associated with a successful transplant; physical and psychological turbulence; and re-alignment by learning adaptive strategies to move forward. Critical factors affecting coping included multi-disciplinary healthcare approaches, social support, and individual-level factors. While clinical transplant care was evaluated positively, participants identified gaps in the provision of information and psychosocial support related to graft failure. Graft failure had a profound impact on caregivers especially when they were living donors.

CONCLUSIONS

Our review reports patient-identified priorities for improving care and can help inform research and guideline development that strives to improve the care of patients with graft failure.

Effect of kidney replacement therapy modality after first kidney graft failure on second kidney transplantation outcomes

Background

There is a lack of information regarding which is the best dialysis technique after kidney transplant (KT) failure. The aim of this study is to compare the effect of kidney replacement therapy modality-peritoneal dialysis (TX-PD-TX), haemodialysis (TX-HD-TX) and preemptive deceased donor retransplantation (TX-TX) on patient survival and second KT outcomes.

Methods

A retrospective observational study from the Catalan Renal Registry was carried out. We included adult patients with failing of their first KT from 2000 to 2018.

Results

Among 2045 patients, 1829 started on HD (89.4%), 168 on PD (8.2%) and 48 (2.4%) received a preemptive KT. Non-inclusion on the KT waiting list and HD were associated with worse patient survival. For patients included on the waiting list, the probability of human leucocyte antigens (HLA) sensitization and to receive a second KT was similar in HD and PD. A total of 776 patients received a second KT (38%), 656 in TX-HD-TX, 72 in TX-PD-TX and 48 in TX-TX groups. Adjusted mortality after second KT was higher in TX-HD-TX patients compared with TX-TX and TX-PD-TX groups, without differences between TX-TX and TX-PD-TX groups. Death-censored second graft survival was similar in all three groups.

Conclusions

Our results suggest that after first KT failure, PD is superior to HD in reducing mortality in candidates for a second KT without options for preemptive retransplantation.

Challenges in the Management of the Patient with a Failing Kidney Graft: A Narrative Review

Patients with a failed kidney allograft have steadily increase in recent years and returning to dialysis after graft loss is one of the most difficult transitions for chronic kidney disease patients and their assistant physicians. The management of these patients is complex and encompasses the treatment of chronic kidney disease complications, dialysis restart and access planning, immunosuppression withdrawal, graft nephrectomy, and evaluation for a potential retransplant. In recent years, several groups have focused on the management of the patient with a failing renal graft and expert recommendations are arising. A review of Pubmed, ScienceDirect and the Cochrane Library was performed focusing on the specific care of these patients, from the management of low clearance complications to concerns with a subsequent kidney transplant. Conclusion: There is a growing interest in the failing renal graft and new approaches to improve these patients' outcomes are being defined including specific multidisciplinary programs, individualized immunosuppression withdrawal schemes, and strategies to prevent HLA sensitization and increase retransplant rates.

Strategies to Overcome HLA Sensitization and Improve Access to Retransplantation after Kidney Graft Loss

An increasing number of patients waitlisted for kidney transplantation have a previously failed graft. Retransplantation provides a significant improvement in morbidity, mortality, and quality of life when compared to dialysis. However, HLA sensitization is a major barrier to kidney retransplantation and the majority of the highly sensitized patients are waiting for a subsequent kidney transplant. A multidisciplinary team that includes immunogeneticists, transplant nephrologists and surgeons, and adequate allocation policies is fundamental to increase access to a kidney retransplant. A review of Pubmed, ScienceDirect, and the Cochrane Library was performed on the challenges of kidney retransplantation after graft loss, focusing on the HLA barrier and new strategies to overcome sensitization. Conclusion: Technical advances in immunogenetics, new desensitization protocols, and complex allocation programs have emerged in recent years to provide a new hope to kidney recipients with a previously failed graft.

Immunosuppressant Medication Use in Patients with Kidney Allograft Failure: A Prospective Multi-Center Canadian Cohort Study

Background: Patients with kidney transplant failure have a high risk of hospitalization and death due to infection. The optimal use of immunosuppressants after transplant failure remains uncertain and clinical practice varies widely. Methods: This prospective cohort study enrolled patients within 21 days of starting dialysis after transplant failure in 16 Canadian centers. Immunosuppressant medication use, death, hospitalized infection, rejection of the failed allograft, and panel reactive anti-HLA antibodies (PRA) were determined at 1, 3, 6 , and 12 months and bi-annually until death, repeat transplantation, or loss to follow-up. Results: The 269 study patients were followed for a median of 558 days. There were 33 deaths, 143 patients hospitalized for infection, and 21 rejections. Most patients (65%) continued immunosuppressants, 20% continued prednisone only, while 15% discontinued all immunosuppressants. In multivariable models, patients who continued immunosuppressants had a lower risk of death (HR =0.40, 95% CI, 0.17-0.93) and were not at increased risk of hospitalized infection (HR 1.81; 95% CI 0.82 to 4.0) compared to patients who discontinued all immunosuppressants or continued prednisone only. The mean class I and class II PRA increased from 11% to 27% and 25% to 47%, respectively, but did not differ by immunosuppressant use. Continuation of immunosuppressants was not protective of rejection of the failed allograft (HR 0.81, 95% CI, 0.22-2.94). Conclusions: Prolonged use of immunosuppressants greater than one year after transplant failure was not associated with a higher risk of death or hospitalized infection but was insufficient to prevent higher anti-HLA antibodies or rejection of the failed allograft.

Kidney recipients with allograft failure, transition of kidney care (KRAFT): A survey of contemporary practices of transplant providers

Kidney allograft failure and return to dialysis carry a high risk of morbidity. A practice survey was developed by the AST Kidney Pancreas Community of Practice workgroup and distributed electronically to the AST members. There were 104 respondents who represented 92 kidney transplant centers. Most survey respondents were transplant nephrologists at academic centers. The most common approach to immunosuppression management was to withdraw the antimetabolite first (73%), while only 12% responded they would withdraw calcineurin inhibitor (CNI) first. More than 60% reported that the availability of a living donor is the most important factor in their decision to taper immunosuppression, followed by risk of infection, risk of sensitization, frailty, and side effects of medications. More than half of respondents reported that embolization was either not available or offered to less than 10% as an option for surgical intervention. Majority reported that ≤50% of failed allograft patients were re-listed before dialysis, and less than a quarter of transplant nephrologists performed frequent visits with their patients with failed kidney allograft after they return to dialysis. This survey demonstrates heterogeneity in the care of patients with a failing allograft and the need for more evidence to guide improvements in clinical practice related to transition of care.

Significance of HLA-DQ in kidney transplantation: time to reevaluate human leukocyte antigen matching priorities to improve transplant outcomes? An expert review and recommendations

The weight of human leukocyte antigen (HLA) matching in kidney allocation algorithms, especially in the United States, has been devalued in a stepwise manner, supported by the introduction of modern immunosuppression. The intent was further to reduce the observed ethnic/racial disparity, as data emerged associating HLA matching with decreased access to transplantation for African American patients. In recent years, it has been increasingly recognized that a leading cause of graft loss is chronic antibody-mediated rejection, attributed to the development of de novo antibodies against mismatched donor HLA expressed on the graft. These antibodies are most frequently against donor HLA-DQ molecules. Beyond their impact on graft survival, generation of de novo donor-specific HLA antibodies also leads to increased sensitization, as measured by panel-reactive antibody metrics. Consequently, access to transplantation for patients returning to the waitlist in need of a second transplant is compromised. Herein, we address the implications of reduced HLA matching policies in kidney allocation. We highlight the observed diminished outcome data, the significant financial burden, the long-term health consequences, and, more important, the unintended consequences. We further provide recommendations to examine the impact of donor-recipient HLA class II and specifically HLA-DQα₁β₁ mismatching, focusing on collection of appropriate data, application of creative simulation approaches, and reconsideration of best practices to reduce inequalities while optimizing patient outcomes.

Comparison of outcomes of peritoneal dialysis between patients after failed kidney transplant and transplant-naïve patients: a meta-analysis of observational studies

PURPOSE

The influence of prior failed kidney transplants on outcomes of peritoneal dialysis (PD) is unclear. Thus, we conducted a systematic review and meta-analysis to compare the outcomes of patients initiating PD after a failed kidney transplant with those initiating PD without a prior history of kidney transplantation.

METHODS

We searched PubMed, Embase, CENTRAL, and Google Scholar databases from inception until 25 November 2020. Our meta-analysis considered the absolute number of events of mortality, technical failures, and patients with peritonitis, and we also pooled multi-variable adjusted hazard ratios (HR).

RESULTS

We included 12 retrospective studies. For absolute number of events, our analysis indicated no statistically significant difference in technique failure [RR, 1.14; 95% CI, 0.80-1.61; I²=52%; p = 0.48], number of patients with peritonitis [RR, 1.13; 95% CI, 0.97-1.32; I²=5%; p = 0.11] and mortality [RR, 1.00; 95% CI, 0.67-1.50; I²=63%; p = 0.99] between the study groups. The pooled analysis of adjusted HRs indicated no statistically significant difference in the risk of technique failure [HR, 1.25; 95% CI, 0.88-1.78; I²=79%; p = 0.22], peritonitis [HR, 1.04; 95% CI, 0.72-1.50; I²=76%; p = 0.85] and mortality [HR, 1.24; 95% CI, 0.77-2.00; I²=66%; p = 0.38] between the study groups.

CONCLUSION

Patients with kidney transplant failure initiating PD do not have an increased risk of mortality, technique failure, or peritonitis as compared to transplant-naïve patients initiating PD. Further studies are needed to evaluate the impact of prior and ongoing immunosuppression on PD outcomes.

Plasma Vitamin C and Risk of Late Graft Failure in Kidney Transplant Recipients: Results of the TransplantLines Biobank and Cohort Study

Recent studies have shown that depletion of vitamin C is frequent in outpatient kidney transplant recipients (KTR) and that vitamin C is inversely associated with risk of death. Whether plasma vitamin C is associated with death-censored kidney graft failure remains unknown. We investigated KTR who participated in the TransplantLines Insulin Resistance and Inflammation Biobank and Cohort Study. The primary outcome was graft failure (restart of dialysis or re-transplantation). Overall and stratified (pinteraction < 0.1) multivariable-adjusted Cox regression analyses are presented here. Among 598 KTR (age 51 ± 12 years-old; 55% males), baseline median (IQR) plasma vitamin C was 44.0 (31.0-55.3) µmol/L. Through a median follow-up of 9.5 (IQR, 6.3‒10.2) years, 75 KTR developed graft failure (34, 26, and 15 events over increasing tertiles of vitamin C, log-rank p < 0.001). Plasma vitamin C was inversely associated with risk of graft failure (HR per 1-SD increment, 0.69; 95% CI 0.54-0.89; p = 0.004), particularly among KTR with triglycerides ≥1.9 mmol/L (HR 0.46; 95% CI 0.30-0.70; p < 0.001; pinteraction = 0.01) and among KTR with HDL cholesterol ≥0.91 mmol/L (HR 0.56; 95% CI 0.38-0.84; p = 0.01; pinteraction = 0.04). These findings remained materially unchanged in multivariable-adjusted analyses (donor, recipient, and transplant characteristics, including estimated glomerular filtration rate and proteinuria), were consistent in categorical analyses according to tertiles of plasma vitamin C, and robust after exclusion of outliers. Plasma vitamin C in outpatient KTR is inversely associated with risk of late graft failure. Whether plasma vitamin C‒targeted therapeutic strategies represent novel opportunities to ease important burden of graft failure necessitates further studies.

Toward Advancing Long-Term Outcomes of Kidney Transplantation with Artificial Intelligence

After decades of pioneering advances and improvements, kidney transplantation is now the renal replacement therapy of choice for most patients with end-stage kidney disease (ESKD). Despite this success, the high risk of premature death and frequent occurrence of graft failure remain important clinical and research challenges. The current burst of studies and other innovative initiatives using artificial intelligence (AI) for a wide range of analytical and practical applications in biomedical areas seems to correlate with the same trend observed in publications in the kidney transplantation field, and points toward the potential of such novel approaches to address the aforementioned aim of improving long-term outcomes of kidney transplant recipients (KTR). However, at the same time, this trend underscores now more than ever the old methodological challenges and potential threats that the research and clinical community needs to be aware of and actively look after with regard to AI-driven evidence. The purpose of this narrative mini-review is to explore challenges for obtaining applicable and adequate kidney transplant data for analyses using AI techniques to develop prediction models, and to propose next steps in the field. We make a call to act toward establishing the strong collaborations needed to bring innovative synergies further augmented by AI, which have the potential to impact the long-term care of KTR. We encourage researchers and clinicians to submit their invaluable research, including original clinical and imaging studies, database studies from registries, meta-analyses, and AI research in the kidney transplantation field.

Impact of dialysis modality on morbimortality of kidney transplant recipients after allograft failure. Analysis in the presence of competing events

BACKGROUND AND OBJECTIVE

The number of patients who start dialysis due to graft failure increases every day. The best dialysis modality for this type of patient is not well defined and most patients are referred to HD. The objective of our study is to evaluate the impact of the dialysis modality on morbidity and mortality in transplant patients who start dialysis after graft failure.

MATERIAL AND METHODS

A multicentre retrospective observation and cohort study was performed to compare the evolution of patients who started dialysis after graft failure from January 2000 to December 2013. One group started on PD and the other on HD. The patients were followed until the change of dialysis technique, retransplantation or death. Anthropometric data, comorbidity, estimated glomerular filtration rate (eGFR) at start of dialysis, the presence of an optimal access for dialysis, the appearance of graft intolerance and retransplantation were analyzed. We studied the causes for the first 10 hospital admissions after starting dialysis. For the statistical analysis, the presence of competitive events that hindered the observation of the event of interest, death or hospital admission was analyzed.

RESULTS

175 patients were included, 86 in DP and 89 in HD. The patients who started PD were younger, had less comorbidity and started dialysis with lower eGFR than those on HD. The mean follow-up was 34 ± 33 months, with a median of 24 months (IQR 7-50 months), Patients on HD had longer follow-up than patients on PD (35 vs. 18 months, p = < 0.001). The mortality risk factors were age sHR 1.06 (95% CI: 1.03-1.106, p = 0.000), non-optimal use of access for dialysis sHR 3.00 (95% CI: 1.507-5.982, p = 0.028) and the dialysis modality sHR (PD/HD) 0.36 (95% CI: 0.148-0.890, p = 0.028). Patients on PD had a lower risk of hospital admission sHR [DP/HD] 0.52 (95% CI: 0.369-0.743, p = < 0.001) and less probability of developing graft intolerance HR 0.307 (95% CI 0.142-0.758, p = 0.009).

CONCLUSIONS

With the limitations of a retrospective and non-randomized study, it is the first time nationwide that PD shows in terms of survival to be better than HD during the first year and a half after the kidney graft failure. The presence of a non-optimal access for dialysis was an independent and modifiable risk factor for mortality. Early referral of patients to advanced chronic kidney disease units is essential for the patient to choose the technique that best suits their circumstances and to prepare an optimal access for the start of dialysis.

Outcomes of an Inpatient Dialysis Start in Patients With Kidney Graft Failure: A Population-Based Multicentre Cohort Study

Background:

The frequency and outcomes of starting maintenance dialysis in the hospital as an inpatient in kidney transplant recipients with graft failure are poorly understood.

Objective:

To determine the frequency of inpatient dialysis starts in patients with kidney graft failure and examine whether dialysis start status (hospital inpatient vs outpatient setting) is associated with all-cause mortality and kidney re-transplantation.

Design:

Population-based cohort study.

Setting:

We used linked administrative healthcare databases from Ontario, Canada.

Patients:

We included 1164 patients with kidney graft failure from 1994 to 2016.

Measurements:

All-cause mortality and kidney re-transplantation.

Methods:

The cumulative incidence function was used to calculate the cumulative incidence of all-cause mortality and kidney re-transplantation, accounting for competing risks. Subdistribution hazard ratios from the Fine and Gray model were used to examine the relationship between inpatient dialysis starts (vs outpatient dialysis start [reference]) and the dependent variables (ie, mortality or re-transplant).

Results:

We included 1164 patients with kidney graft failure. More than half (55.8%) of patients with kidney graft failure, initiated dialysis as an inpatient. Compared with outpatient dialysis starters, inpatient dialysis starters had a significantly higher cumulative incidence of mortality and a significantly lower incidence of kidney re-transplantation (P < .001). The 10-year cumulative incidence of mortality was 51.9% (95% confidence interval [CI]: 47.4, 56.9%) (inpatient) and 35.3% (95% CI: 31.1, 40.1%) (outpatient). After adjusting for clinical characteristics, we found inpatient dialysis starters had a significantly increased hazard of mortality in the first year after graft failure (hazard ratio: 2.18 [95% CI: 1.43, 3.33]) but at 1+ years there was no significant difference between groups.

Limitations:

Possibility of residual confounding and unable to determine inpatient dialysis starts that were unavoidable.

Conclusions:

In this study we identified that most patients with kidney graft failure had inpatient dialysis starts, which was associated with an increased risk of mortality. Further research is needed to better understand the reasons for an inpatient dialysis start in this patient population.

Long-term outcomes after kidney transplant failure and variables related to risk of death and probability of retransplant: Results from a single-center cohort study in Brazil

Background

Returning to dialysis after kidney graft loss (GL) is associated with a high risk of mortality, mainly in the first 3–6 months. The follow-up of patients with GL should be extended to better understand crude patient outcomes, mainly in emerging countries, where the transplantation activity has increased.

Methods

This is a historical single-center cohort study conducted in an emerging country (Brazil) that included 115 transplant patients with kidney allograft failure who were followed for 44.1 (21.4; 72.6) months after GL. The outcomes were death or retransplantation after GL calculated by Kaplan-Meier and log-rank tests. Proportional hazard ratios for death and retransplantation were assessed by Cox regression.

Results

The 5-year probability of retransplantation was 38.7% (95% CI: 26.1%-51.2%) and that of death was 37.7% (95% CI: 24.9%-50.5%); OR = 1.03 (95% CI: 0.71–1.70) and P = 0.66. The likelihood of retransplantation was higher in patients who resumed dialysis with higher levels of hemoglobin (HR = 1.22; 95% CI = 1.04–1.43; P = 0.01) and lower in blood type O patients (HR = 0.48; 95% CI = 0.25–0.93; P = 0.03), which was associated with a lower frequency of retransplantation with a subsequent living-donor kidney. On the other hand, the risk of death was significantly associated with Charlson comorbidity index (HR for each point = 1.37; 95% CI 1.19–1.50; P<0.001), and residual eGFR at the time when patients had resumed to dialysis (HR for each mL = 1.14; 95% CI = 1.05–1.25; P = 0.002). The trend toward a lower risk of death when patients had resumed to dialysis using AV fistula access was observed (HR = 0.50; 95% CI 0.25–1.02; P = 0.06), while a higher risk seems to be associated with the number of previous engraftment (HR = 2.01; 95% CI 0.99–4.07; P = 0.05).

Conclusions

The 5-year probability of retransplantation was not less than that of death. Variables related to the probability of retransplantation were hemoglobin level before resuming dialysis and ABO blood type, while the risk of death was associated with comorbidities and residual eGFR.

Returning to dialysis after kidney allograft failure: the experience of the Italian Registry of Paediatric Chronic Dialysis

BACKGROUND

The need for dialysis after kidney allograft failure (DAGF) is among the top five reasons for dialysis initiation, making this an important topic in clinical nephrology. However, data are scarce on dialysis choice after transplantation and clinical outcomes for DAGF in children.

METHODS

Patients receiving chronic dialysis < 18 years were recorded from January 1991 to January 2019 by the Italian Registry of Pediatric Chronic Dialysis (IRPCD). We investigated factors influencing choice of dialysis modality, patient outcome in terms of mortality, switching dialysis modality, and kidney transplantation.

RESULTS

Among 118 patients receiving DAGF, 41 (35%) were treated with peritoneal dialysis (PD), and 77 (65%) with haemodialysis (HD). Significant predictors for treatment with PD were younger age at dialysis start (OR 0.85 per year increase [95%CI 0.72-1.00]) and PD use before kidney transplantation (OR 8.20 [95%CI 1.82-37.01]). Patients entering DAGF in more recent eras (OR 0.87 per year increase [95%CI 0.80-0.94]) and with more than one dialysis modality before kidney transplantation (OR 0.56 for being treated with PD [0.12-2.59]) were more likely to be initiated on HD. As compared to patients on HD, those treated with PD exhibited increased but non-significant mortality risk (HR 2.15 [95%CI 0.54-8.6]; p = 0.28) and higher prevalence of dialysis-related complications during DAGF (p = 0.002) CONCLUSIONS: Patients entering DAGF in more recent years are more likely to be initiated on HD. In this specific population of children, use of PD seems associated with a more complicated course. A higher resolution version of the Graphical abstract is available as Supplementary information.

Management of patients with a failed kidney transplant: what should we do?

The number of kidney transplant recipients returning to dialysis after graft failure is steadily increasing over time. Patients with a failed kidney transplant have been shown to have a significant increase in mortality compared with patients with a functioning graft or patients initiating dialysis for the first time. Moreover, the risk for infectious complications, cardiovascular disease and malignancy is greater than in the dialysis population due to the frequent maintenance of low-dose immunosuppression, which is required to reduce the risk of allosensitization, particularly in patients with the prospect of retransplantation from a living donor. The management of these patients present several controversial opinions and clinical guidelines are lacking. This article aims to review the leading evidence on the main issues in the management of patients with failed transplant, including the ideal timing and modality of dialysis reinitiation, the indications for an allograft nephrectomy or the correct management of immunosuppression during graft failure. In summary, retransplantation is a feasible option that should be considered in patients with graft failure and may help to minimize the morbidity and mortality risk associated with dialysis reinitiation.

Treatment options for localised renal cell carcinoma of the transplanted kidney

Currently, there is no consensus among the transplant community about the treatment of renal cell carcinoma (RCC) of the transplanted kidney. Until recently, graftectomy was universally considered the golden standard, regardless of the characteristics of the neoplasm. Due to the encouraging results observed in native kidneys, conservative options such as nephron-sparing surgery (NSS) (enucleation and partial nephrectomy) and ablative therapy (radiofrequency ablation, cryoablation, microwave ablation, high-intensity focused ultrasound, and irreversible electroporation) have been progressively used in carefully selected recipients with early-stage allograft RCC. Available reports show excellent patient survival, optimal oncological outcome, and preserved renal function with acceptable complication rates. Nevertheless, the rarity and the heterogeneity of the disease, the number of options available, and the lack of long-term follow-up data do not allow to adequately define treatment-specific advantages and limitations. The role of active surveillance and immunosuppression management remain also debated. In order to offer a better insight into this difficult topic and to help clinicians choose the best therapy for their patients, we performed and extensive review of the literature. We focused on epidemiology, clinical presentation, diagnostic work up, staging strategies, tumour characteristics, treatment modalities, and follow-up protocols. Our research confirms that both NSS and focal ablation represent a valuable alternative to graftectomy for kidney transplant recipients with American Joint Committee on Cancer stage T1aN0M0 RCC. Data on T1bN0M0 lesions are scarce but suggest extra caution. Properly designed multi-centre prospective clinical trials are warranted.

Risk factors for death in kidney transplant patients: analysis from a large protocol biopsy registry

BACKGROUND

Identification and quantification of the relevant factors for death can improve patients' individual risk assessment and decision-making. We used a well-documented patient cohort (n = 892) in a renal transplant programme with protocol biopsies to establish multivariable Cox models for risk assessment at 3 and 12 months post-transplantation.

METHODS

Patients transplanted between 2000 and 2007 were observed up to 11 years (total observation 5227 patient-years; median 5.9 years). Loss to follow-up was negligible (n = 15). A total of 2251 protocol biopsies and 1214 biopsies for cause were performed. All rejections and clinical borderline rejections in protocol biopsies were treated.

RESULTS

Overall 10-year patient survival was 78%, with inferior survival of patients with graft loss and superior survival of patients with living-donor transplantation. Eight factors were common in the models at 3 and 12 months, including age, pre-transplant heart failure and a score of cardiovascular disease and type 2 diabetes, post-transplant urinary tract infection, treatment of rejection, new-onset heart failure, coronary events and malignancies. Additional variables of the model at 3 months included deceased donor transplantation, transplant lymphocele, BK virus nephropathy and severe infections. Graft function and graft loss were significant factors of the model at 12 months. Internal validation and validation with a separate cohort of patients (n = 349) demonstrated good discrimination of the models.

CONCLUSIONS

The identified factors indicate the important areas that need special attention in the pre- and post-transplant care of renal transplant patients. On the basis of these models, we provide nomograms as a tool to weigh individual risks that may contribute to decreased survival.

Clinical outcomes of incident peritoneal dialysis patients coming from kidney transplantation program: A case-control study

Introduction

Brazil ranks second in the absolute number of transplantations in the world. Despite improvements in graft survival, many patients will progress to graft loss and return to dialysis. Concerns exist regarding adverse clinical outcomes in this population when undergone peritoneal dialysis (PD).

Objective

To compare the occurrence of mortality, technique failure, and peritonitis among incident patients in PD coming from either Tx or pre-dialysis treatment.

Methodology

A retrospective study in which 47 adult patients with Tx failure (Tx group) were matched for age, gender, diabetes mellitus (DM), modality and start year of PD, with 1:1 predialysis patient (nTx group). The Fine-Gray competing risk model was used to analyze mortality and technique failure.

Results

Compared to nTx, the Tx group had a lower body mass index, serum potassium, and albumin concentrations. A higher ferritin level, transferrin saturation and the number of patients with positive serology for viral hepatitis were also observed in the Tx group. In the multivariate analysis, patients of the Tx group had 4.4-times higher risk of death (p = 0.007), with infection as the main cause. Technique failure and peritonitis were similar in both groups.

Conclusion

Previous Tx is a risk factor for mortality but not for technique failure or peritonitis in incident patients on a PD program.

Returning to haemodialysis after kidney allograft failure: a survival study with propensity score matching

BACKGROUND

Patients who return to dialysis after kidney allograft failure (KAF) are classically considered to have lower survival rates than their transplant-naïve incident dialysis counterparts. However, this observation in previous comparisons could be due to poor matching between the two populations.

METHODS

To compare survival rates between patients who returned to haemodialysis (HD) after KAF versus transplant-naïve incident HD patients, we performed a retrospective study using the EuCliD® database (European Clinical Database) that collects data from Fresenius Medical Care (FMC) outpatient HD facilities in Spain. Propensity score matching (PSM) was performed to homogenize both populations.

RESULTS

This study included 5216 patients from 65 different FMC clinics between 2009 and 2014. Naïve incident HD patients were mostly male, older, comorbid and more commonly had catheters as vascular access. During the study follow-up, 3915 patients exited, of whom 1534 died. The mean survival time for the entire cohort was 4.86 years [95% confidence interval (CI) 4.78-4.94]. Univariate Cox analysis indicated higher mortality risk among transplant-naïve incident HD patients [hazard ratio (HR) 1.728; 95% CI 1.35-2.21; P < 0.001). However, this difference was no longer significant after multivariate adjustment. After applying PSM to minimize the bias due to indication issue, we obtained an adjusted population composed of 480 naïve and 240 KAF patients. The results analysing the PSM-adjusted cohort confirmed similar survival in both cohorts (log-rank, 3.34; P = 0.068; HR 1.382; 95% CI 0.97-1.95; P = 0.069).

CONCLUSIONS

When comparing properly matched patient groups, patients who return to HD after KAF present similar survival than survival than transplant-naïve incident patients.

Prescribing Hemodialysis or Hemodiafiltration: When One Size Does Not Fit All the Proposal of a Personalized Approach Based on Comorbidity and Nutritional Status

There is no simple way to prescribe hemodialysis. Changes in the dialysis population, improvements in dialysis techniques, and different attitudes towards the initiation of dialysis have influenced treatment goals and, consequently, dialysis prescription. However, in clinical practice prescription of dialysis still often follows a "one size fits all" rule, and there is no agreed distinction between treatment goals for the younger, lower-risk population, and for older, high comorbidity patients. In the younger dialysis population, efficiency is our main goal, as assessed by the demonstrated close relationship between depuration (tested by kinetic adequacy) and survival. In the ageing dialysis population, tolerance is probably a better objective: "good dialysis" should allow the patient to attain a stable metabolic balance with minimal dialysis-related morbidity. We would like therefore to open the discussion on a personalized approach to dialysis prescription, focused on efficiency in younger patients and on tolerance in older ones, based on life expectancy, comorbidity, residual kidney function, and nutritional status, with particular attention placed on elderly, high-comorbidity populations, such as the ones presently treated in most European centers. Prescription of dialysis includes reaching decisions on the following elements: dialysis modality (hemodialysis (HD) or hemodiafiltration (HDF)); type of membrane (permeability, surface); and the frequency and duration of sessions. Blood and dialysate flow, anticoagulation, and reinfusion (in HDF) are also briefly discussed. The approach described in this concept paper was developed considering the following items: nutritional markers and integrated scores (albumin, pre-albumin, cholesterol; body size, Body Mass Index (BMI), Malnutrition Inflammation Score (MIS), and Subjective Global Assessment (SGA)); life expectancy (age, comorbidity (Charlson Index), and dialysis vintage); kinetic goals (Kt/V, normalized protein catabolic rate (n-PCR), calcium phosphate, parathyroid hormone (PTH), beta-2 microglobulin); technical aspects including vascular access (fistula versus catheter, degree of functionality); residual kidney function and weight gain; and dialysis tolerance (intradialytic hypotension, post-dialysis fatigue, and subjective evaluation of the effect of dialysis on quality of life). In the era of personalized medicine, we hope the approach described in this concept paper, which requires validation but has the merit of providing innovation, may be a first step towards raising attention on this issue and will be of help in guiding dialysis choices that exploit the extraordinary potential of the present dialysis "menu".

Transplant Patients With Failing Renal Allografts

Progress in patient care and immunosuppressive medications has resulted in improved allograft survival in the early posttransplant period; however, substantial graft loss continues in the long term. Therefore, the number of dialysis patients with failed allografts is increasing progressively. These patients have a worse prognosis than naive dialysis patients. Cardiovascular causes are the leading cause of death, followed by infections and malignancies. Delay in return to dialysis, a chronic inflammatory state, infections, and cancer are contributing factors to mortality, whereas type of dialysis modality does not have a significant effect on outcomes. Graft nephrectomy is a risky operation; therefore, it should not be a routine procedure and rather should be performed only when indicated. Overall, most grafts are left in place, whereas graft nephrectomy is performed in atients with graft intolerance syndrome. Management of immunosuppressive drugs after graft failure is controversial. In the case of maintaining immunosuppression, there is increased risk of infections, cardiovascular diseases, and malignancies and also steroid-related adverse effects. On the other hand, discontinuation of immunosuppressants may result in loss of residual allograft function and also acute graft inflammation. Together, immunosuppressive drugs are almost always discontinued in these patients because of their inherent adverse effects. Considering the sequence of cessation, first antiproliferative drugs are stopped, followed by calcineurin inhibitors, and finally steroids. Because many studies show a clear survival benefit, every attempt should be made for a retransplant in patients with failed renal allografts.