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

Expanding the access to kidney transplantation: Strategies for kidney transplant programs

Kidney transplantation is the most successful kidney replacement therapy available, resulting in improved recipient survival and societal cost savings. Yet, nearly 70 years after the first successful kidney transplant, there are still numerous barriers and untapped opportunities that constrain the access to transplant. The literature describing these barriers is extensive, but the practices and processes to solve them are less clear. Solutions must be multidisciplinary and be the product of strong partnerships among patients, their networks, health care providers, and transplant programs. Transparency in the referral, evaluation, and listing process as well as organ selection are paramount to build such partnerships. Providing early culturally congruent and patient-centered education as well as maximizing the use of local resources to facilitate the transplant work up should be prioritized. Every opportunity to facilitate pre-emptive kidney transplantation and living donation must be taken. Promoting the use of telemedicine and kidney paired donation as standards of care can positively impact the work up completion and maximize the chances of a living donor kidney transplant.

Clinical relevance of HLA-DQ eplet mismatch and maintenance immunosuppression with risk of allosensitization after kidney transplant failure

The optimal immunosuppression management in patients with a failed kidney transplant remains uncertain. This study analyzed the association of class II HLA eplet mismatches and maintenance immunosuppression with allosensitization after graft failure in a well characterized cohort of 21 patients who failed a first kidney transplant. A clinically meaningful increase in cPRA in this study was defined as the cPRA that resulted in 50% reduction in the compatible donor pool measured from the time of transplant failure until the time of repeat transplantation, death, or end of study. The median cPRA at the time of failure was 12.13% (interquartile ranges = 0.00%, 83.72%) which increased to 62.76% (IQR = 4.34%, 99.18%) during the median follow-up of 27 (IQR = 18, 39) months. High HLA-DQ eplet mismatches were significantly associated with an increased risk of developing a clinically meaningful increase in cPRA (p = 0.02) and de novo DQ donor-specific antibody against the failed allograft (p = 0.02). We did not observe these associations in patients with high HLA-DR eplet mismatches. Most of the patients (88%) with a clinically meaningful increase in cPRA had both a high DQ eplet mismatch and a reduction in their immunosuppression, suggesting the association is modified by immunosuppression. The findings suggest HLA-DQ eplet mismatch analysis may serve as a useful tool to guide future clinical studies and trials which assess the management of immunosuppression in transplant failure patients who are repeat transplant candidates.

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.

Kidney retransplantation outcomes in adults aged 70 and older: Analysis of risk factors and survival

BACKGROUND

An increasing number of older patients are undergoing kidney transplant. Because of a finite longevity, more patients will be faced with failing allografts. At present there is a limited understanding of the benefits and risks associated with kidney retransplantation in this challenging population.

METHODS

We performed a retrospective analysis of the Organ Procurement and Transplantation Network database of all adults ≥70 undergoing kidney retransplant from January 1, 2014 to December 31, 2022. We examined patient and graft survival of retransplanted patients compared to first time transplants. We also analyzed the risk factors that impacted the survival.

RESULTS

During the study period there has been a significant rise in the number of retransplants performed, with 631 patients undergoing the procedure. Although clinically insignificant, overall graft, and patient survival rates were slightly lower in the retransplant group compared to the primary transplant group. With retransplant, patient survival was 91.3%, 75.6%, and 56.9% compared to 93.4%, 81.4%, and 64.4% with primary transplant at 1, 3, and 5 years, respectively. With retransplant, graft survival was 89.5%, 73.5%, 57.4% compared to 91.5%, 79.0%, and 63.6% in a primary transplant group at 1, 3, and 5 years, respectively. Multivariable analysis showed that factors predicting poor survival included longer time on dialysis before retransplantation and decreased functional capacity. No survival difference was noted between recipients of deceased versus living donor kidneys. Patients who underwent retransplantation before initiating dialysis had better patient and graft survival.

CONCLUSION

Patients aged ≥70 achieve satisfactory outcomes following kidney retransplantation, highlighting that chronologic age should not preclude this medically complex population from this life-saving procedure. Improvement in functional status and timely retransplantation are the key factors to successful outcome.

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.

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.

Proteomic analysis investigating kidney transplantation outcomes- a scoping review

BACKGROUND

Kidney transplantation is the optimal treatment option for most patients with end-stage kidney disease given the significantly lower morbidity and mortality rates compared to remaining on dialysis. Rejection and graft failure remain common in transplant recipients with limited improvement in long-term transplant outcomes despite therapeutic advances. There is an unmet need in the development of non-invasive biomarkers that specifically monitor graft function and predict transplant pathologies that affect outcomes. Despite the potential of proteomic investigatory approaches, up to now, no candidate biomarkers of sufficient sensitivity or specificity have translated into clinical use. The aim of this review was to collate and summarise protein findings and protein pathways implicated in the literature to date, and potentially flag putative biomarkers worth validating in independent patient cohorts.

METHODS

This review followed the Joanna Briggs' Institute Methodology for a scoping review. MedlineALL, Embase, Web of Science Core Collection, Scopus and Google Scholar databases were searched from inception until December 2022. Abstract and full text review were undertaken independently by two reviewers. Data was collated using a pre-designed data extraction tool.

RESULTS

One hundred one articles met the inclusion criteria. The majority were single-centre retrospective studies of small sample size. Mass spectrometry was the most used technique to evaluate differentially expressed proteins between diagnostic groups and studies identified various candidate biomarkers such as immune or structural proteins.

DISCUSSION

Putative immune or structural protein candidate biomarkers have been identified using proteomic techniques in multiple sample types including urine, serum and fluid used to perfuse donor kidneys. The most consistent findings implicated proteins associated with tubular dysfunction and immunological regulatory pathways such as leukocyte trafficking. However, clinical translation and adoption of candidate biomarkers is limited, and these will require comprehensive evaluation in larger prospective, multicentre trials.

Impact of Calcineurin Inhibitor-Based Immunosuppression Maintenance During the Dialysis Period After Kidney Transplant Failure on the Next Kidney Graft Outcome: A Retrospective Multicenter Study With Propensity Score Analysis

The impact of immunosuppressive therapy (IS) strategies after kidney transplant failure (KTF) on potential future new grafts is poorly established. We assessed the potential benefit of calcineurin inhibitor (CNI)-based IS maintenance throughout the dialysis period on the outcome of the second kidney transplant (KT). We identified 407 patients who underwent a second KT between January 2008 and December 2018 at four French KT centers. Inverse probability of treatment weighting was used to control for potential confounding. We included 205 patients with similar baseline characteristics at KTF: a total of 53 received at least CNIs on the retransplant day (G-CNI), and 152 did not receive any IS (G-STOP). On the retransplant date, G-STOP patients experienced a longer pretransplant dialysis time, were more often hyperimmunized, and underwent more expanded-criteria donor KTs than G-CNI patients. During the second KT follow-up period, rejection episodes were similar in both groups. The 10-year survival rates without death and dialysis were 98.7% and 59.5% in G-CNI and G-STOP patients, respectively. In the multivariable analysis, CNI-based IS maintenance was associated with better survival (hazard ratio: 0.08; 95% confidence interval: 0.01-0.58, p = 0.01). CNI-based IS maintenance throughout the dialysis period after KTF may improve retransplantation outcomes.

Deep learning of 2D-Restructured gene expression representations for improved low-sample therapeutic response prediction

Clinical outcome prediction is important for stratified therapeutics. Machine learning (ML) and deep learning (DL) methods facilitate therapeutic response prediction from transcriptomic profiles of cells and clinical samples. Clinical transcriptomic DL is challenged by the low-sample sizes (34-286 subjects), high-dimensionality (up to 21,653 genes) and unordered nature of clinical transcriptomic data. The established methods rely on ML algorithms at accuracy levels of 0.6-0.8 AUC/ACC values. Low-sample DL algorithms are needed for enhanced prediction capability. Here, an unsupervised manifold-guided algorithm was employed for restructuring transcriptomic data into ordered image-like 2D-representations, followed by efficient DL of these 2D-representations with deep ConvNets. Our DL models significantly outperformed the state-of-the-art (SOTA) ML models on 82% of 17 low-sample benchmark datasets (53% with >0.05 AUC/ACC improvement). They are more robust than the SOTA models in cross-cohort prediction tasks, and in identifying robust biomarkers and response-dependent variational patterns consistent with experimental indications.

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.

Catecholamine Vasopressor Exposure Is Associated With Early Poor Allograft Function and Adverse Events in Living Donor Kidney Transplant Recipients

BACKGROUND

Hypoperfusion leads to allograft injury during kidney transplantation. Catecholamine vasopressors are used to maintain blood pressure in the perioperative period but have demonstrated negative outcomes in the deceased-donor kidney transplant population. Little is known regarding living donor kidney transplants (LDKTs) and vasopressor use. The aim of this study is to describe the incidence of vasopressor use in LDKT and characterize its effects on allograft function and patient outcomes.

METHODS

This retrospective, observational cohort study included adult patients who underwent an isolated LDKT between August 1, 2017, and September 1, 2018. Patients were divided into those who received perioperative vasopressors and those who did not. The primary objective was to compare allograft function between LDKT recipients that received vasopressors and those who did not. Secondary outcomes included safety endpoints and the identification of clinical variables associated with vasopressor use.

RESULTS

A total of 67 patients received an LDKT during the study period. Of those, 25 (37%) received perioperative vasopressors, and 42 (62%) did not. Poor graft function, as defined by the development of slow or delayed graft function, occurred more frequently in patients receiving perioperative vasopressors compared with those who did not (6 [24%] vs 1 [2.4%], P = .016). In multivariable regression modeling, only perioperative vasopressors were statistically significantly associated with poor graft function. In addition, patients exposed to vasopressors experienced more postoperative arrhythmias (8 [32%] vs 1 [4.8%], P = .0025).

CONCLUSION

Using perioperative vasopressors was independently associated with worsened early renal allograft function, including delayed graft function and adverse events in the LDKT population.

Risk factors for infection in patients with a failed kidney allograft on immunosuppressive medications

Patients with a failing kidney allograft are often continued on immunosuppression (IS) to preserve residual kidney function and prevent allosensitization. It has been previously accepted that maintaining patients on immunosuppressive therapy results in an increased risk of infection, hospitalization, and mortality. However, as the management of IS in patients with a failed kidney allograft continues to evolve, it is important to review the data regarding associations between infection and specific immunosuppression regimens. We present a review of the literature of failed kidney allograft management and infection risk, and discuss practices for infection prevention. Fifteen studies, published from 1995 to 2022, which investigated the experience of patients with failed allograft and infection, were identified. Infection was most commonly documented as a general event, but when specified, included infections caused by Candida, Mycobacterium tuberculosis, and Aspergillus. In addition, the definition of reduced "IS" varied from decreased doses of a triple drug regimen to monotherapy, whereas others did not specify which medications patients were receiving. Despite attempts at lowering net immunosuppression, patients with failed allografts remain at risk of acquiring opportunistic and non-opportunistic infections. Although opportunistic infections secondary to IS are expected, somewhat surprisingly, it appears that the greatest risk of infection may be related to complications of dialysis. Therefore, mitigating strategies, such as planning for an arteriovenous (AV) fistula over a hemodialysis catheter placement, may reduce infection risk. Additional studies are needed to provide more information regarding the types and timing of infection in the setting of a failed kidney allograft. In addition, more data are needed regarding specific medications, doses, and timing of taper of IS to guide future patient management and inform strategies for infection surveillance and prophylaxis.

Continuation of immunosuppression vs. immunosuppression weaning in potential repeat kidney transplant candidates: a care management perspective

Management of immunosuppression in patients with a failing or failed kidney transplant requires a complete assessment of their clinical condition. One of the major considerations in determining immunosuppression is whether or not such an individual is considered a candidate for re-transplantation. Withdrawal of immunosuppression in a re-transplant candidate can result in allosensitization and markedly reduce the chances of a repeat transplant. In this review, we summarize the effects of immunosuppression reduction on HLA sensitization, discuss the impacts of allosensitization in these patients, and explore reduction protocols and future directions. Risks of chronic immunosuppression, medical management of the failing allograft, and the effect of nephrectomy are covered elsewhere in this issue.

A non-muscle myosin heavy chain 9 genetic variant is associated with graft failure following kidney transplantation

BACKGROUND

Despite current matching efforts to identify optimal donor-recipient pairs for kidney transplantation, alloimmunity remains a major source of late transplant failure. Additional genetic parameters in donor-recipient matching could help improve longterm outcomes. Here, we studied the impact of a non-muscle myosin heavy chain 9 gene (MYH9) polymorphism on allograft failure.

METHODS

We conducted an observational cohort study, analyzing the DNA of 1,271 kidney donor-recipient transplant pairs from a single academic hospital for the MYH9 rs11089788 C>A polymorphism. The associations of the MYH9 genotype with risk of graft failure, biopsy-proven acute rejection (BPAR), and delayed graft function (DGF) were estimated.

RESULTS

A trend was seen in the association between the MYH9 polymorphism in the recipient and graft failure (recessive model, p = 0.056), but not for the MYH9 polymorphism in the donor. The AA-genotype MYH9 polymorphism in recipients was associated with higher risk of DGF (p = 0.03) and BPAR (p = 0.021), although significance was lost after adjusting for covariates (p = 0.15 and p = 0.10, respectively). The combined presence of the MYH9 polymorphism in donor-recipient pairs was associated with poor long-term kidney allograft survival (p = 0.04), in which recipients with an AA genotype receiving a graft with an AA genotype had the worst outcomes. After adjustment, this combined genotype remained significantly associated with 15-year death-censored kidney graft survival (hazard ratio, 1.68; 95% confidence interval, 1.05-2.70; p = 0.03).

CONCLUSION

Our results reveal that recipients with an AA-genotype MYH9 polymorphism receiving a donor kidney with an AA genotype have significantly elevated risk of graft failure after kidney transplantation.

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.

Management of the Failing Kidney Transplant: Challenges and Solutions

The kidneys are the most transplanted organs, and the number of failed kidney transplants that require reinstitution of renal replacement therapy in patients is on the increase. Increased mortality has been noted in patients with failed grafts compared with transplant- naïve patients with chronic kidney disease who are treated with dialysis. Issues such as management of immunosuppression, the need for transplant nephrectomy, addressing the increased risk of cardiovascular events, malignancies, and infections are debatable and often based on individual or hospital practices. The optimal timing and modality of renal replacement therapy to be reinitiated are sometimes blurred, with considerable variations among physician practices. Guidelines are therefore needed to appropriately manage this special population of patients with the aim of improving outcomes. Here, our objective was to review the current practices in managing patients with failing kidney transplants so that recommendations can be made based on the available evidence.