Characterization of waiting times in a simulation of kidney paired donation

A Systematic Review of Kidney Transplantation Decision Modelling Studies

BACKGROUND

Genome-based precision medicine strategies promise to minimize premature graft loss after renal transplantation, through precision approaches to immune compatibility matching between kidney donors and recipients. The potential adoption of this technology calls for important changes to clinical management processes and allocation policy. Such potential policy change decisions may be supported by decision models from health economics, comparative effectiveness research and operations management.

OBJECTIVE

We used a systematic approach to identify and extract information about models published in the kidney transplantation literature and provide an overview of the status of our collective model-based knowledge about the kidney transplant process.

METHODS

Database searches were conducted in MEDLINE, Embase, Web of Science and other sources, for reviews and primary studies. We reviewed all English-language papers that presented a model that could be a tool to support decision making in kidney transplantation. Data were extracted on the clinical context and modelling methods used.

RESULTS

A total of 144 studies were included, most of which focused on a single component of the transplantation process, such as immunosuppressive therapy or donor-recipient matching and organ allocation policies. Pre- and post-transplant processes have rarely been modelled together.

CONCLUSION

A whole-disease modelling approach is preferred to inform precision medicine policy, given its potential upstream implementation in the treatment pathway. This requires consideration of pre- and post-transplant natural history, risk factors for allograft dysfunction and failure, and other post-transplant outcomes. Our call is for greater collaboration across disciplines and whole-disease modelling approaches to more accurately simulate complex policy decisions about the integration of precision medicine tools in kidney transplantation.

Protection of transplants against antibody-mediated injuries: from xenotransplantation to allogeneic transplantation, mechanisms and therapeutic insights

Long-term allograft survival in allotransplantation, especially in kidney and heart transplantation, is mainly limited by the occurrence of antibody-mediated rejection due to anti-Human Leukocyte Antigen antibodies. These types of rejection are difficult to handle and chronic endothelial damages are often irreversible. In the settings of ABO-incompatible transplantation and xenotransplantation, the presence of antibodies targeting graft antigens is not always associated with rejection. This resistance to antibodies toxicity seems to associate changes in endothelial cells phenotype and modification of the immune response. We describe here these mechanisms with a special focus on endothelial cells resistance to antibodies. Endothelial protection against anti-HLA antibodies has been described in vitro and in animal models, but do not seem to be a common feature in immunized allograft recipients. Complement regulation and anti-apoptotic molecules expression appear to be common features in all these settings. Lastly, pharmacological interventions that may promote endothelial cell protection against donor specific antibodies will be described.

Rethinking incompatibility in kidney transplantation

Donor/recipient incompatibility in kidney transplantation classically refers to ABO/HLA-incompatibility. Kidney paired donation (KPD) was historically established to circumvent ABO/HLA-incompatibility, with the goal of identifying ABO/HLA-compatible matches. However, there is a broad range of donor factors known to impact recipient outcomes beyond ABO/HLA-incompatibility, such as age and weight, and quantitative tools are now available to empirically compare potential living donors across many of these factors, such as the living donor kidney donor profile index (LKDPI). Moreover, the detrimental impact of mismatch at other HLA antigens (such as DQ) and epitope mismatching on posttransplant outcomes has become increasingly recognized. Thus, it is time for a new paradigm of incompatibility that considers all of these risks factors together in assessing donor/recipient compatibility and the potential utility for KPD. Under this new paradigm of incompatibility, we show how the LKDPI and other tools can be used to identify donor/recipient incompatibilities that could be improved through KPD, even for those with a traditionally "compatible" living donor.

Gender disparities in transplantation

PURPOSE OF REVIEW

Transplantation is the life-saving therapy for patients suffering from end-organ failure, and as such, equitable access to transplantation (ATT) is of paramount importance. Unfortunately, gender/sex-based disparities exist, and despite the transplant community's awareness of this injustice, gender/sex-based disparities have persisted for more than two decades. Importantly, no legislation or allocation policy has addressed inequity in ATT that women disproportionately face. In fact, introduction of the model for end-stage liver disease-based liver allocation system in 2002 widened the gender disparity gap and it continues to be in effect today. Moreover, women suffering from kidney disease are consistently less likely to be referred for transplant evaluation and subsequently less likely to achieve a kidney transplant, yet they comprise the majority of living kidney donors.

RECENT FINDINGS

Acknowledging gender/sex-based disparities in ATT is the first step toward interventions aimed at mitigating this long-standing injustice in healthcare.

SUMMARY

This article provides a background of end-stage liver and kidney disease in women, summarizes the existing literature describing the issue of gender disparity in ATT, and identifies potential areas of intervention and future investigation.

A review of imlifidase in solid organ transplantation

INTRODUCTION

Sensitization to human leukocyte antigens has long posed an obstacle to organ transplantation. With desensitization protocol refinement, new drug development, and organ allocation policy changes, access to transplant for sensitized patients has never been greater. Yet in spite of these advances the problem of donor-specific antibody remains incompletely solved, and many patients remain poorly served by the therapies that do exist. Area covered: Imlifidase is a new drug with a mechanism of action that enables it to transiently yet efficiently eliminate donor-specific antibody over a much more rapid time course than any heretofore existing therapy. This unique property suggests that imlifidase may have far-reaching potential for patients in whom donor-specific antibodies may preclude successful transplantation. Below follows a review of the clinical experience with imlifidase to date as well as a discussion of the transplant applications that eagerly await the availability of this novel agent. Expert opinion: Imlifidase is a first-in-class pharmaceutical agent that safely and efficiently cleaves IgG, and holds promise to be a game-changer for sensitized patients in need of lifesaving organ transplants.

How do highly sensitized patients get kidney transplants in the United States? Trends over the last decade

Prioritization of highly sensitized (HS) candidates under the kidney allocation system (KAS) and growth of large, multicenter kidney-paired donation (KPD) clearinghouses have broadened the transplant modalities available to HS candidates. To quantify temporal trends in utilization of these modalities, we used SRTR data from 2009 to 2017 to study 39 907 adult HS (cPRA ≥ 80%) waitlisted candidates and 19 003 recipients. We used competing risks regression to quantify temporal trends in likelihood of DDKT, KPD, and non-KPD LDKT for HS candidates (Era 1: January 1, 2009-December 31, 2011; Era 2: January 1, 2012-December 3, 2014; Era 3: December 4, 2014-December 31, 2017). Although the likelihood of DDKT and KPD increased over time for all HS candidates (adjusted subhazard ratio [aSHR] Era 3 vs 1 for DDKT: 1.74 1.851.97 , P < .001 and for KPD: 1.70 2.202.84 , P < .001), the likelihood of non-KPD LDKT decreased (aSHR: 0.69 0.820.97 , P = .02). However, these changes affected HS recipients differently based on cPRA. Among recipients, more cPRA 98%-99.9% and 99.9%+ recipients underwent DDKT (96.2% in Era 3% vs 59.1% in Era 1 for cPRA 99.9%+), whereas fewer underwent non-KPD LDKT (1.9% vs 30.9%) or KPD (2.0% vs 10.0%). Although KAS increased DDKT likelihood for the most HS candidates, it also decreased the use of non-KPD LDKT to transplant cPRA 98%+ candidates.

Current protocols and outcomes of ABO-incompatible kidney transplantation

One of the principal obstacles in transplantation from living donors is that approximately 30% are immunologically incompatible because of the presence in the recipient of antibodies directed against the human leukocyte antigen system of the donor or because of the incompatibility of the ABO system. The aim of this review is to describe the more recent data from the literature on the different protocols used and the clinical outcomes of ABO-incompatible kidney transplantation. Two different strategies are used to overcome these barriers: desensitization of the recipient to remove the antibodies and to prevent their rebound after transplantation and the exchange of organs between two or more pairs. The largest part of this review is dedicated to describing the techniques of desensitization. Even if the first reports of successful renal transplantation between ABO-incompatible pairs have been published by 1980, the number of ABO-incompatible transplants increased substantially in this century because of our improved knowledge of the immune system and the availability of new drugs. Rituximab has substantially replaced splenectomy. The technique of apheresis has improved and more recently a tailored desensitization proved to be the more efficient strategy avoiding an excess of immunosuppression with the related side effects. Recent reports document outcomes for such transplantation similar to the outcomes of standard transplantation.

Human B1 Cells are the Main Blood Group A-Specific B Cells That Have a Moderate Correlation With Anti-A Antibody Titer

Background

Anti-carbohydrate antibody responses, including those of anti-blood group ABO antibodies, are yet to be thoroughly studied in humans. Because anti-ABO antibody-mediated rejection is a key hurdle in ABO-incompatible transplantation, it is important to understand the cellular mechanism of anti-ABO responses. We aimed to identify the main human B cell subsets that produce anti-ABO antibodies by analyzing the correlation between B cell subsets and anti-ABO antibody titers.

Methods

Blood group A-binding B cells were analyzed in peritoneal fluid and peripheral blood samples from 43 patients undergoing peritoneal dialysis and 18 healthy volunteers with blood group B or O. The correlation between each blood group A-specific B cell subset and anti-A antibody titer was then analyzed using Pearson's correlation analysis.

Results

Blood group A-binding B cells were enriched in CD27⁺CD43⁺CD1c⁻ B1, CD5⁺ B1, CD11b⁺ B1, and CD27⁺CD43⁺CD1c⁺ marginal zone-B1 cells in peripheral blood. Blood group A-specific B1 cells (P=0.029 and R=0.356 for IgM; P=0.049 and R=0.325 for IgG) and marginal zone-B1 cells (P=0.011 and R=0.410 for IgM) were positively correlated with anti-A antibody titer. Further analysis of peritoneal B cells confirmed B1 cell enrichment in the peritoneal cavity but showed no difference in blood group A-specific B1 cell enrichment between the peritoneal cavity and peripheral blood.

Conclusions

Human B1 cells are the key blood group A-specific B cells that have a moderate correlation with anti-A antibody titer and therefore constitute a potential therapeutic target for successful ABO-incompatible transplantation.

Mitigating Racial and Sex Disparities in Access to Living Donor Kidney Transplantation: Impact of the Nation's Longest Single-center Kidney Chain

OBJECTIVE

In this study, we sought to assess likelihood of living donor kidney transplantation (LDKT) within a single-center kidney transplant waitlist, by race and sex, after implementation of an incompatible program.

SUMMARY BACKGROUND DATA

Disparities in access to LDKT exist among minority women and may be partially explained by antigen sensitization secondary to prior pregnancies, transplants, or blood transfusions, creating difficulty finding compatible matches. To address these and other obstacles, an incompatible LDKT program, incorporating desensitization and kidney paired donation, was created at our institution.

METHODS

A retrospective cohort study was performed among our kidney transplant waitlist candidates (n = 8895). Multivariable Cox regression was utilized, comparing likelihood of LDKT before (era 1: 01/2007-01/2013) and after (era 2: 01/2013-11/2018) implementation of the incompatible program. Candidates were stratified by race [white vs minority (nonwhite)], sex, and breadth of sensitization.

RESULTS

Program implementation resulted in the nation's longest single-center kidney chain, and likelihood of LDKT increased by 70% for whites [adjusted hazard ratio (aHR) 1.70; 95% confidence interval (CI), 1.46-1.99] and more than 100% for minorities (aHR 2.05; 95% CI, 1.60-2.62). Improvement in access to LDKT was greatest among sensitized minority women [calculated panel reactive antibody (cPRA) 11%-49%: aHR 4.79; 95% CI, 2.27-10.11; cPRA 50%-100%: aHR 4.09; 95% CI, 1.89-8.82].

CONCLUSIONS

Implementation of an incompatible program, and the resulting nation's longest single-center kidney chain, mitigated disparities in access to LDKT among minorities, specifically sensitized women. Extrapolation of this success on a national level may further serve these vulnerable populations.

Evaluation of Living Kidney Donor and Recipient Candidates: The Experience of Our Center

PURPOSE

We evaluated potential kidney living donors and recipients for donation in our transplant center.

MATERIALS AND METHODS

Candidates to be kidney living donors and kidney transplant recipients (KTxR) were retrospectively evaluated. All candidates were informed and assessed by transplant coordinator and nephrologists. All data were obtained from archive records.

RESULTS

The mean ages of 194 kidney living donors and 182 KTxR were 45.7 ± 13.1 and 37.7 ± 14.6 years, respectively. Percentages of female candidates were 55.2% and 34.1% among kidney living donors and KTxR respectively. The kidney living donor candidates were the patients' mothers (27.3%), spouses (24.2%), siblings (21.6%), fathers (12.4%), and sons or daughters (6.2%) of KTxRs and others (8.2%). The numbers of donors with body mass index (BMI) > 30 kg/m² and > 35kg/m² were 56 (28.9%) and 17 (8.8%) respectively. Due to withdrawal from donation (21.2%) and renal problems (15.3%), 85/194 (43.8%) kidney living donors were excluded. Of the remaining 51/182 (28%) KTxR candidates, 26/182 (14.2%) were unsuitable because their panel-reactive antibody (PRA) > 20%. Sixty-six KTxR were performed in our center. Nine donor candidates were rejected due to obesity (BMI > 35 kg/m²).

CONCLUSION

Most of our kidney living donors were mothers, housewives, and uneducated persons. Due to high percentages of suitability among candidates of KTxRs and kidney living donors as 72% and 56% may be an advantage for living kidney donation. However, PRA positivity in the recipients drew attention as a major barrier. The high incidence of obesity among the donor candidates suggests that societies must be more sensitive about this issue.

Matching Kidneys with Priority in Kidney Exchange Programs

Kidney exchanges were developed to match kidney failure patients with willing but incompatible donors to other donor-patient pairs. Finding a match in a large candidate pool can be modeled as an integer program. However, these exchanges accumulate participants with characteristics that increase the difficulty of finding a match and, therefore, increase patients’ waiting time. Therefore, we sought to fine-tune the formulation of the integer program by more accurately assigning priorities to patients based on their difficulty of matching. We provide a detailed formulation of prioritized kidney exchange and propose a novel prioritization algorithm. Our approach takes advantage of the global knowledge of the donor-patient compatibility within a pool of pairs and calculates an iterative, paired match power (iPMP) to represent the donor-patient pairs’ abilities to match. Monte Carlo simulation shows that an algorithm using the iPMP reduces the waiting time more than using paired match power (PMP) for the difficult-to-match pairs with hazard ratios of 1.3480 and 1.1100, respectively. Thus, the iPMP may be a more accurate assessment of the difficulty of matching a pair in a pool than PMP is, and its use may improve matching algorithms being used to match donors and recipients.

Solid organ transplantation in the 21st century

Solid organ transplantation (SOT) has emerged from an experimental approach in the 20th century to now being an established and practical definitive treatment option for patients with end-organ dysfunction. The evolution of SOT has seen the field progress rapidly over the past few decades with incorporation of a variety of solid organs-liver, kidney, pancreas, heart, and lung-into the donor pool. New advancements in surgical technique have allowed for more efficient and refined multi-organ procurements with minimal complications and decreased ischemic injury events. Additionally, immunosuppression therapy has also seen advancements with the expansion of immunosuppressive protocols to dampen the host immune response and improve short and long-term graft survival. However, the field of SOT faces new barriers, most importantly the expanding demand for SOT that is outpacing the current supply. Allocation protocols have been developed in an attempt to address these concerns. Other avenues for SOT are also being explored to increase the donor pool, including split-liver donor transplants, islet cell implantation for pancreas transplants, and xenotransplantation. The future of SOT is bright with exciting new research being explored to overcome current obstacles.

Kidney exchange match rates in a large multicenter clearinghouse

Kidney paired donation (KPD) can facilitate living donor transplantation for candidates with an incompatible donor, but requires waiting for a match while experiencing the morbidity of dialysis. The balance between waiting for KPD vs desensitization or deceased donor transplantation relies on the ability to estimate KPD wait times. We studied donor/candidate pairs in the National Kidney Registry (NKR), a large multicenter KPD clearinghouse, between October 2011 and September 2015 using a competing-risk framework. Among 1894 candidates, 52% were male, median age was 50 years, 66% were white, 59% had blood type O, 42% had panel reactive antibody (PRA)>80, and 50% obtained KPD through NKR. Median times to KPD ranged from 2 months for candidates with ABO-A and PRA 0, to over a year for candidates with ABO-O or PRA 98+. Candidates with PRA 80-97 and 98+ were 23% (95% confidence interval , 6%-37%) and 83% (78%-87%) less likely to be matched than PRA 0 candidates. ABO-O candidates were 67% (61%-73%) less likely to be matched than ABO-A candidates. Candidates with ABO-B or ABO-O donors were 31% (10%-56%) and 118% (82%-162%) more likely to match than those with ABO-A donors. Providers should counsel candidates about realistic, individualized expectations for KPD, especially in the context of their alternative treatment options.

Effect of match-run frequencies on the number of transplants and waiting times in kidney exchange

Numerous kidney exchange (kidney paired donation [KPD]) registries in the United States have gradually shifted to high-frequency match-runs, raising the question of whether this harms the number of transplants. We conducted simulations using clinical data from 2 KPD registries-the Alliance for Paired Donation, which runs multihospital exchanges, and Methodist San Antonio, which runs single-center exchanges-to study how the frequency of match-runs impacts the number of transplants and the average waiting times. We simulate the options facing each of the 2 registries by repeated resampling from their historical pools of patient-donor pairs and nondirected donors, with arrival and departure rates corresponding to the historical data. We find that longer intervals between match-runs do not increase the total number of transplants, and that prioritizing highly sensitized patients is more effective than waiting longer between match-runs for transplanting highly sensitized patients. While we do not find that frequent match-runs result in fewer transplanted pairs, we do find that increasing arrival rates of new pairs improves both the fraction of transplanted pairs and waiting times.

Harnessing Scientific and Technological Advances to Improve Equity in Kidney Allocation Policies

We reported that current assignment of HLA-DQ is a barrier to organ allocation. Here we simulated the impact of incorporating HLA-DQ antigens and antibodies as A/B and αβ allelic variants, respectively, on calculated panel reactive antibody (cPRA) and probability of finding potential compatible donors (PCD). A cohort of 1224 donors and 2075 sensitized candidates was analyzed using HLA-DQαβ allelic (study) versus serologic (current practice) nomenclature. A significant (p < 10^-4 ) decrease in cPRA was observed with higher impact for male versus female, and first transplant versus retransplant (p < 10^-4 ), affecting mostly patients with moderate cPRA (30-80%). Consequently, the number of patients qualifying for 100% cPRA points according to the United Network for Organ Sharing-Kidney Allocation System decreased by 37%. More critically, by using allelic versus serologic nomenclature for HLA-DQ, the number of PCDs for all patients was increased, with male and first-transplant patients showing a higher expansion compared with female and retransplants. Patients of blood group O showed the highest benefit. The goal of reporting unacceptable antigens is to improve accuracy of virtual crossmatching and increase the likelihood of finding immunologically compatible donors. Our simulation provides strong support for the need to re-evaluate the use of allele typing and how HLA-DQ antigens and antibodies are incorporated into allocation policies to ensure equity.

KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors

The 2017 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors is intended to assist medical professionals who evaluate living kidney donor candidates and provide care before, during and after donation. The guideline development process followed the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach and guideline recommendations are based on systematic reviews of relevant studies that included critical appraisal of the quality of the evidence and the strength of recommendations. However, many recommendations, for which there was no evidence or no systematic search for evidence was undertaken by the Evidence Review Team, were issued as ungraded expert opinion recommendations. The guideline work group concluded that a comprehensive approach to risk assessment should replace decisions based on assessments of single risk factors in isolation. Original data analyses were undertaken to produce a "proof-in-concept" risk-prediction model for kidney failure to support a framework for quantitative risk assessment in the donor candidate evaluation and defensible shared decision making. This framework is grounded in the simultaneous consideration of each candidate's profile of demographic and health characteristics. The processes and framework for the donor candidate evaluation are presented, along with recommendations for optimal care before, during, and after donation. Limitations of the evidence are discussed, especially regarding the lack of definitive prospective studies and clinical outcome trials. Suggestions for future research, including the need for continued refinement of long-term risk prediction and novel approaches to estimating donation-attributable risks, are also provided.In citing this document, the following format should be used: Kidney Disease: Improving Global Outcomes (KDIGO) Living Kidney Donor Work Group. KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors. Transplantation. 2017;101(Suppl 8S):S1-S109.

Characteristics of compatible pair participants in kidney paired donation at a single center

Compatible pairs of living kidney donors and their intended recipients can enter into kidney paired donation (KPD) and facilitate additional living donor kidney transplants (LDKTs). We examined 11 compatible pairs (the intended recipients and their intended, compatible donors) who participated in KPD, along with the recipients' 11 matched, exchange donors. The 11 pairs participated in 10 separate exchanges (three were multicenter exchanges) that included 33 total LDKTs (22 additional LDKTs). All the intended donors were blood group O and female, with a mean living kidney donor profile index (LKDPI) of 27.6 (SD 16.8). The matched donors had a mean LKDPI of 9.4 (SD 31.7). Compatible pairs entered KPD for altruistic reasons (N=2) or due to mismatch of age (N=7) or body/kidney size (N=2) between the recipient and intended donor. In four cases, retrospective calculation of the LKDPI revealed that the matched donor had a higher LKDPI than the intended donor. Of the 22 recipients of LDKTs enabled by the compatible pairs, three were highly sensitized, with PRA >80%. In conclusion, most compatible pairs entered into KPD so that the recipient could receive a LDKT transplant from a donor whose age or body/kidney size were more favorable to post-transplant outcomes.

Six-year outcomes in broadly HLA-sensitized living donor transplant recipients desensitized with intravenous immunoglobulin and rituximab

Desensitization with intravenous immunoglobulin (IVIG) and rituximab can improve transplantation rates in broadly sensitized kidney transplant recipients. However, long-term outcomes are lacking. Here we analyze long-term outcomes in living donor kidney transplant recipients desensitized with this regimen and compare them to low-risk recipients. Living donor kidney transplants that took place between July 2006 and December 2010 were considered retrospectively. The primary end point of the study was death-censored allograft survival at last follow-up. Secondary end points included patient survival, incidence of rejection, glomerular filtration rate (GFR), and proteinuria. There were 66 sensitized and 111 low-risk patients included. Average follow-up was 68 months. There was no difference in long-term patient or graft survival. The rate of rejection was similar in the groups with more early rejection in the sensitized group and more late rejection in the low-risk group. There was more antibody-mediated rejection in the sensitized group. Estimated GFR was similar during the follow-up period. Risk factors for rejection included a positive cross-match (HR: 2.4 CI: 1.35-4.40) and age (HR: 0.97 CI: 0.95-0.99). Desensitization with IVIG and rituximab has good long-term results with graft outcomes similar to non-HLA-sensitized patients despite higher immunologic risk.

First International Paired Exchange Kidney Transplantations of Turkey

OBJECTIVE

We estimated that many patients on the waiting list for kidney transplantation in Turkey have immunologicaly incompatible suitable living donors. Paired exchange kidney transplantation (PETx) is superior to desensitization for patients with incompatible donors. Recently we decided to begin an international PETx program.

METHODS

We report three international living related paired kidney transplantations which occurred between May 14,2013, and March 7, 2014. The international donor and recipient operations were performed at Medical Park Hospital, Antalya, Turkey. All pairs were living related and written proofs were obtained according to Turkish laws. As with the donor procedures, the transplantation procedures were performed at the same time.

RESULTS

The uniqueness of these transplantations was that they are the first international exchange kidney transplantations between Turkey and Kirghizia. Currently all recipients are alive with wel-functioning grafts.

CONCLUSION

In our institute, a 5% increase was obtained in living-related kidney transplantations by the help of PETx on a national basis. We believe that international PETx may also have the potential to expand the donor pool.

Strategies to overcome the ABO barrier in kidney transplantation

Kidney transplantation across the ABO blood group barrier was long considered a contraindication for transplantation, but in an effort to increase donor pools, specific regimens for ABO-incompatible (ABOi) transplantation have been developed. These regimens are now widely used as an integral part of the available treatment options. Various desensitization protocols, commonly based on transient depletion of preformed anti-A and/or anti-B antibodies and modulation of B-cell immunity, enable excellent transplant outcomes, even in the long-term. Nevertheless, the molecular mechanisms behind transplant acceptance facilitated by a short course of anti-humoral treatment are still incompletely understood. With the evolution of efficient clinical programmes, tailoring of recipient preconditioning based on individual donor-recipient blood type combinations and the levels of pretransplant anti-A/B antibodies has become possible. In the context of low antibody titres and/or donor A2 phenotype, immunomodulation and/or apheresis might be dispensable. A concern still exists, however, that ABOi kidney transplantation is associated with an increased risk of surgical and infectious complications, partly owing to the effects of extracorporeal treatment and intensified immunosuppression. Nevertheless, a continuous improvement in desensitization strategies, with the aim of minimizing the immunosuppressive burden, might pave the way to clinical outcomes that are comparable to those achieved in ABO-compatible transplantation.

Assessing the efficacy of kidney paired donation--performance of an integrated three-site program

BACKGROUND

Kidney paired donation (KPD) has emerged as a viable option for renal transplant candidates with incompatible living donors. The aim of this study was to assess the "performance" of a three-site KPD program that allowed screening of multiple donors per recipient.

METHODS

We reviewed retrospectively the activity of our KPD program involving three centers under the same institutional umbrella. The primary goal was to achieve a transplant that was both ABO compatible and had a negative or low-positive flow cytometric crossmatch (+XM).

RESULTS

During the 40-month study period, 114 kidney transplant candidates were enrolled-57% resulting from a +XM and 39% resulting from ABO incompatible (ABOi) donors. Important outcomes were as follows: (1) 81 (71%) candidates received a transplant and 33 (29%) were still waiting; (2) 368 donors were evaluated, including 10 nondirected donors; (3) 82% (37/45) of ABOi candidates underwent transplantation; (4) 56% (36/65) of +XM candidates underwent transplantation (however, all but four of these had a cPRA less than 95%); (5) at the end of the study period, 97% (28/29) of +XM candidates still waiting had a cPRA greater than 95%.

CONCLUSIONS

These data suggest evaluating large numbers of donors increases the chances of KPD. Patients with a cPRA greater than 95% are unlikely to receive a negative or low-positive +XM, suggesting the need for desensitization protocols in KPD.

Early clinical complications after ABO-incompatible live-donor kidney transplantation: a national study of Medicare-insured recipients

BACKGROUND

Descriptions of the sequelae of ABO-incompatible (ABOi) kidney transplantation are limited to single-center reports, which may lack power to detect important effects.

METHODS

We examined U.S. Renal Data System registry data to study associations of ABOi live-donor kidney transplantation with clinical complications in a national cohort. Among 14,041 Medicare-insured transplants in 2000 to 2007, 119 non-donor-A2 ABOi transplants were identified. A2-incompatible (n=35) transplants were categorized separately. Infection and hemorrhage events were identified by diagnosis codes on billing claims. Associations of ABO incompatibility with complications were assessed by multivariate Cox regression.

RESULTS

Recipients of ABOi transplants experienced significantly (P<0.05) higher incidence of wound infections (12.7% vs. 7.3%), pneumonia (7.6% vs. 3.8%), and urinary tract infections (UTIs) or pyelonephritis (24.5% vs. 15.3%) in the first 90 days compared with ABO-compatible recipients. In adjusted models, ABO incompatibility was associated with twice the risk of pneumonia (adjusted hazard ratio [aHR], 2.22; 95% confidence interval [CI], 1.14-4.33) and 56% higher risk of UTIs or pyelonephritis (aHR, 1.56; 95% CI, 1.05-2.30) in the first 90 posttransplantation days, and 3.5 times the relative risk of wound infections in days 91 to 365 (aHR, 3.55; 95% CI, 1.92-6.57). ABOi recipients, 19% of whom underwent pre- or peritransplant splenectomy, experienced twice the adjusted risk of early hemorrhage (aHR, 1.96; 95% CI, 1.19-3.24). A2-incompatible transplantation was associated only with early risk of UTIs or pyelonephritis.

CONCLUSION

ABOi transplantation offers patients with potential live donors an additional transplant option but with higher risks of infectious and hemorrhagic complications. Awareness of these complications may help improve protocols for the management of ABOi transplantation.

Foundations and principles of the Canadian living donor paired exchange program

Purpose of review

Kidney paired donation (KPD) remains an important strategy to facilitate transplantation in patients who have a healthy and willing donor, but are unable to proceed with directed donation due to either ABO incompatibility or a positive cross-match against their intended donor.

Sources of information

Personal knowledge, The Canadian Blood Services Database for Living Donor Exchange, published reports and personal communications.

Findings

The national Living Donor Paired Exchange Programme (LDPE) in Canada was established in 2009. 235 transplants were completed of which 190 were registered recipients and 45 were from the deceased donor (DD) wait list. At 1 year, patient survival was 100%, graft survival 98%, with a biopsy proven acute rejection rate of 8%. The mean serum creatinine (Cr) at the end of one year was 109 mmol/l. Donor survival is 100%. Key to success are national standards for antibody testing and cross-matching, and for evaluating donors and recipients, as well infrastructure (software and personnel) to run the program. The structure of the Canadian program is compared with that of other programs in the United Kingdom, Australia, the Netherlands, and the United States.

Limitations

This review does not include information on travel distances and difficulties, or patient satisfaction.

Implications

National collaboration and acceptance of common standards is possible and leads to substantial benefits, especially for those patients who are hardest to match.

What was known before: Kidney paired donation is considered ethically acceptable. National and regional programs have been created in a number of countries.

What this paper adds: Key to the success of the Canadian national program are acceptance of standardized procedures and national and provincial support and oversight.

Successful three-way kidney paired donation with compatible pairs to increase donor pool

Despite heightened international interest in performing living donor kidney paired donation (KPD) transplantation after the publication of a research protocol by Ross and colleagues in 1997, only a few hundred have been performed worldwide. The major obstacle is that many individuals in end-stage renal disease are of blood type O and can only receive an organ from a donor of blood type O, whereas blood type O donors are "universal donors" and will be able to donate directly with an intended recipient of any blood type unless there is a positive crossmatch. To overcome this, patients with compatible but non-HLA identical donors over 45 years of age should be approached for inclusion in KPD program especially O blood group donors. Inclusion of all these additional pairs into the algorithm greatly increases chances of possible matches for O blood group recipients. We report successful three-way KPD transplantation resulting in transplantation of O blood group patient using compatible O blood group donor from India. None of the patients had delayed graft function or rejection and all had stable graft function on discharge without any medical and surgical complications. We need to allocate O blood group kidneys from compatible donors to overcome the barrier of HLA, non-HLA antibodies and other donor related factors to improve transplant quality and long term outcomes. This will increase transplantation of O blood group patients.

Allocation and matching in kidney exchange programs

Living donor kidney transplantation is the preferred treatment for patients suffering from end-stage renal disease. To alleviate the shortage of kidney donors, many advances have been made to improve the utilization of living donors deemed incompatible with their intended recipient. The most prominent of these advances is kidney paired donation (KPD), which matches incompatible patient-donor pairs to facilitate a kidney exchange. This review discusses the various approaches to matching and allocation in KPD. In particular, it focuses on the underlying principles of matching and allocation approaches, the combination of KPD with other strategies such as ABO incompatible transplantation, the organization of KPD, and important future challenges. As the transplant community strives to balance quantity and equity of transplants to achieve the best possible outcomes, determining the right long-term allocation strategy becomes increasingly important. In this light, challenges include making full use of the various modalities that are now available through integrated and optimized matching software, encouragement of transplant centers to fully participate, improving transplant rates by focusing on the expected long-run number of transplants, and selecting uniform allocation criteria to facilitate international pools.

Center-level utilization of kidney paired donation

With many multicenter consortia and a United Network for Organ Sharing program, participation in kidney paired donation (KPD) has become mainstream in the United States and should be feasible for any center that performs live donor kidney transplantation (LDKT). Lack of participation in KPD may significantly disadvantage patients with incompatible donors. To explore utilization of this modality, we analyzed adjusted center-specific KPD rates based on casemix of adult LDKT-eligible patients at 207 centers between 2006 and 2011 using SRTR data. From 2006 to 2008, KPD transplants became more evenly distributed across centers, but from 2008 to 2011 the distribution remained unchanged (Gini coefficient = 0.91 for 2006, 0.76 for 2008 and 0.77 for 2011), showing an unfortunate stall in dissemination. At the 10% of centers with the highest KPD rates, 9.9-38.5% of LDKTs occurred through KPD during 2009-2011; if all centers adopted KPD at rates observed in the very high-KPD centers, the number of KPD transplants per year would increase by a factor of 3.2 (from 494 to 1593). Broader implementation of KPD across a wide number of centers is crucial to properly serve transplant candidates with healthy but incompatible live donors.

Comparison of kidney paired donation transplantations with living related donor kidney transplantation: implications for national kidney paired donation program

BACKGROUND

Kidney Paired Donation (KPD) is a rapidly growing modality for facilitating living related donor kidney transplantation (LRDKTx) for patients who are incompatible with their healthy, willing, and living donors. Data scarcity on the outcome of KPD versus LRDKTx prompted us to review our experience.

MATERIALS AND METHODS

This was a single-center study of 224 patients on regular follow-up, who underwent LRDRTx from January 2010 to June 2012 at our institute. The aim of this study was to compare short-term graft survival, patient survival and rejection rates of KPD (group 1, n = 34) with those of LRDKTx (group 2, n = 190). All the recipients received triple immunosuppression and thymoglobulin induction in KPD group. Kaplan-Meier curves were used for survival analysis. In group 1, mean recipient age was 35.5 ± 13.2 years, 29 were men and mean donor age was 44.4 ± 8.17 years, 10 were men. In group 2, mean recipient age was 29.1 ± 10 years, 155 were men and mean donor age was 47.5 ± 9.69 years, 74 were men. Mean human leukocyte antigen (HLA) matching in group 1 and 2 was 1 versus 3.2 (p < 0.05).

RESULTS

One- and two-year patient survival showed no significant difference between the two groups (97.1%, 97.1% vs. 96.2%, 94.8%, respectively, p = 0.81). Death-censored graft survival also showed no significant difference between the two groups (97.1%, 97.1%, vs. 97.6%, 97.6%, p = 0.73). Acute rejection incidence was also similar (8.7% vs. 9.9%, p > 0.62).

CONCLUSIONS

Our study showed similar graft survival, patient survival and rejection rates of KPD versus LRDKTx over 2 years post-transplantation, encouraging the use of this approach for national KPD program.

Controversies in kidney paired donation

Kidney paired donation represented 10% of living kidney donation in the United States in 2011. National registries around the world and several separate registries in the United States arrange paired donations, although with significant variations in their practices. Concerns about ethical considerations, clinical advisability, and the quantitative effectiveness of these approaches in paired donation result in these variations. For instance, although donor travel can be burdensome and might discourage paired donation, it was nearly universal until convincing analysis showed that living donor kidneys can sustain many hours of cold ischemia time without adverse consequences. Opinions also differ about whether the last donor in a chain of paired donation transplants initiated by a nondirected donor should donate immediately to someone on the deceased donor wait-list (a domino or closed chain) or should be asked to wait some length of time and donate to start another sequence of paired donations later (an open chain); some argue that asking the donor to donate later may be coercive, and others focus on balancing the probability that the waiting donor withdraws versus the number of additional transplants if the chain can be continued. Other controversies in paired donation include simultaneous versus nonsimultaneous donor operations, whether to enroll compatible pairs, and interactions with desensitization protocols. Efforts to expand public awareness of and participation in paired donation are needed to generate more transplant opportunities.

Accumulation of unfavorable clinical and socioeconomic factors precludes living donor kidney transplantation

BACKGROUND

In the past 30 years, the number of living donor kidney transplantations has increased considerably and nowadays outnumbers the deceased donor transplantations in our center. We investigated which socioeconomic and clinical factors influence who undergoes living or deceased donor kidney transplantation.

METHODS

This retrospective study included all 1338 patients who received a kidney transplant between 2000 and 2011 in the Erasmus MC Rotterdam. Clinical and socioeconomic variables were combined in our study. Clinical variables were recipient age, gender, ethnicity, original disease, retransplants, ABO blood type, panel-reactive antibody, previous treatment, and transplantation year. Each recipient's postcode was linked to a postcode area information data base, to extract demographic information on urbanization level, percentage non-Europeans in the area, income, and housing value. Chi-square, analysis of variance, and univariate and multivariate logistic regression analyses were performed.

RESULTS

There were significant differences between the recipients of a living versus deceased donor kidney transplantation. In multivariate logistic regression analyses, 10 variables had a significant influence on the chance of receiving living donor kidney transplantation. Clinical and socioeconomic factors had an independent influence on this chance. Patients with ABO blood type O and B have smaller chances. Highly sensitized and elderly patients have smaller chances especially when combined with a collection of other unfavorable factors. Accumulation of unfavorable factors in non-Europeans prevents their participation in living donation programs.

CONCLUSION

Both clinical and socioeconomic factors are associated with participation in living or deceased donor kidney transplantation. This study highlights the populations that would benefit from educational intervention regarding living donor transplantation.

Living donor age and kidney allograft half-life: implications for living donor paired exchange programs

BACKGROUND AND OBJECTIVES

Living donor paired exchange programs assume that kidneys from living donors are of comparable quality and anticipated longevity. This study determined actual allograft t(1/2) within different recipient age groups (10-year increments) as a function of donor age (5-year increments), and juxtaposed these results against the probabilities of deceased donor transplantation, and exclusion from transplantation (death or removal from the wait-list).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from the US Renal Data System (transplant dates 1988-2003 with follow-up through September 2007) were used to determine allograft t(1/2), whereas data from patients on the United Network for Organ Sharing waiting list between 2003 and 2005 (with follow-up through February 2010) were used to determine wait-list outcomes.

RESULTS

With the exception of recipients aged 18-39 years, who had the best outcomes with donors aged 18-39 years, living donor age between 18 and 64 years had minimal effect on allograft t(1/2) (difference of 1-2 years with no graded association). The probability of deceased donor transplantation after 3 years of wait-listing ranged from 21% to 66% by blood type and level of sensitization, whereas the probability of being excluded from transplantation ranged from 6% to 27% by age, race, and primary renal disease.

CONCLUSIONS

With the exception of recipients aged 18-39 years, living donor age between 18 and 64 years has minimal effect on allograft survival.

The utilization and advantages of an exchange donor program in living donor renal transplantation: a single-center experience

INTRODUCTION

The availability of donors is a major limiting factor in living donor renal transplantation. Approximately one third of patients with end-stage renal disease have willing potential living donors who are blood type or cross-match incompatible. The living donor kidney exchange has become an efficient solution for recipients in this situation. We analyzed the outcome and advantages of an exchange donor program compared with ABO-incompatible transplantation and desensitized protocol transplantation for highly sensitized patients.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 152 exchange donor cases from 1991 to 2010. We analyzed the risk factors, outcomes, matching factors, complication rates, and acute rejection rates of this program compared with other alternative strategies.

RESULTS

In our center, 22% of total living donor kidney transplantations were performed through an exchange program and an expanded donor pool. The graft survival, complication, and acute rejection rates were not significantly different compared with the alternatives. The severe complication rates were lower than with the alternatives and the immunosuppressant protocol and preoperative preparation were simpler. Blood type O recipients who registered in the exchange program showed no significant differences from the living related groups (P = .45), which were similar to the proportions for other ABO types. Upon multivariate analysis, an acute rejection episode and use of mycophenolate mofetil (MMF) were significant factors associated with graft survival (P = .015 and P = .007; odds ratio [OR] 5.968 and 7.324; 95% confidence interval [CI] .003-.533 and .098-.690).

CONCLUSION

Although exchange donor programs are not the sole solution, they show several advantages, such as the prescription of standard immunosuppression, simple preoperative preparation, low cost, and modest rates of severe complications compared with ABO-incompatible transplantation or desensitized protocols.

The aggressive phenotype: center-level patterns in the utilization of suboptimal kidneys

Despite the fact that suboptimal kidneys have worse outcomes, differences in waiting times and wait-list mortality have led to variations in the use of these kidneys. It is unknown whether aggressive center-level use of one type of suboptimal graft clusters with aggressive use of other types of suboptimal grafts, and what center characteristics are associated with an overall aggressive phenotype. United Network for Organ Sharing (UNOS) data from 2005 to 2009 for adult kidney transplant recipients was aggregated to the center level. An aggressiveness score was assigned to each center based on usage of suboptimal grafts. Deceased-donor transplant volume correlated with aggressiveness in lower volume, but not higher volume centers. Aggressive centers were mostly found in regions 2 and 9. Aggressiveness was associated with wait-list size (RR 1.69, 95% CI 1.20-2.34, p = 0.002), organ shortage (RR 2.30, 95% CI 1.57-3.37, p < 0.001) and waiting times (RR 1.75, 95% CI 1.20-2.57, p = 0.004). No centers in single-center OPOs were classified as aggressive. In cluster analysis, the most aggressive centers were aggressive in all metrics and vice versa; however, centers with intermediate aggressiveness had phenotypic patterns in their usage of suboptimal kidneys. In conclusion, wait-list size, waiting times, geographic region and OPO competition seem to be driving factors in center-level aggressiveness.

Using donor exchange paradigms with desensitization to enhance transplant rates among highly sensitized patients

PURPOSE OF REVIEW

Many sensitized patients have willing live donors but are unable to use them because of a human leukocyte antigen (HLA) incompatibility. The options for these patients include: remaining on the deceased-donor list, entering a kidney-paired donation scheme, or undergoing desensitization with high-dose IVIg or plasmapheresis and low-dose IVIg.

RECENT FINDINGS

Mathematical simulations verified by actual data from several national kidney-paired donation (KPD) programs has shed light on which donor/recipient phenotypes are likely to benefit from each transplant modality. Pairs that are easy to match are likely to receive compatible kidneys in a KPD. Those who are hard to match may be better served by desensitization. The phenotype which is both hard to match and hard to desensitize due to board and strong HLA reactivity are most likely to be transplanted by a hybrid modality utilizing desensitization after identifying a more immunologically favorable donor in a KPD.

SUMMARY

Recent outcomes from desensitization in which starting donor-specific antibody strength is low have been very good. For broadly sensitized patients with a high-strength cross-match, searching for a better donor in a KPD pool can facilitate a safer, less expensive, and more successful desensitization treatment course.

Paired kidney donor exchanges and antibody reduction therapy: novel methods to ameliorate disparate access to living donor kidney transplantation in ethnic minorities

BACKGROUND

Currently ethnic minority patients comprise 60% of patients listed for kidney transplantation in the US; however, they receive only 55% of deceased donor renal transplants and 25% of living donor renal transplants. Ethnic disparities in access to kidney transplantation result in increased morbidity and mortality for minority patients with end-stage renal disease. Because these patients remain dialysis dependent for longer durations, they are more prone to the development of HLA antibodies that further delay the possibility of receiving a successful kidney transplant.

STUDY DESIGN

Two to 4 pretransplant and post-transplant plasma exchanges and i.v. immunoglobulin were used to lower donor-specific antibody levels to less than 1:16 dilution; cell lytic therapy was used additionally in some cases. Match pairing by virtual cross-matching was performed to identify the maximal exchange benefit. Sixty candidates for renal transplantation were placed into 4 paired kidney exchanges and/or underwent antibody reduction therapy.

RESULTS

Sixty living donor renal transplants were performed by paired exchange pools and/or antibody reduction therapy in recipients whose original intended donors had ABO or HLA incompatibilities or both (24 desensitization and 36 paired kidney exchanges). Successful transplants were performed in 38 ethnic minorities, of which 33 were African American. Twenty-two recipients were white. Graft and patient survival was 100% at 6 months; graft function (mean serum creatinine 1.4 g/dL) and acute rejection rates (20%) have been comparable to traditional live donor kidney transplantation.

CONCLUSIONS

Paired kidney donor exchange pools with antibody reduction therapy can allow successful transplant in difficult to match recipients. This approach can address kidney transplant disparities.

Living donor exchange programs: theory and practice

BACKGROUND

The crisis in organ availability has triggered innovative approaches to meet a rapidly expanding worldwide demand for donor kidneys. HLA and ABO incompatibility represents one of the most significant barriers to optimizing the utilization of living donors. Kidney paired donation (KPD) allows patients with incompatible live donors to receive compatible or better-matched organs by exchanging donors.

SOURCES OF DATA

The data presented in this review have been published and represent the most up-to-date sources of the theory and practice of KPD.

AREAS OF AGREEMENT

There is wide agreement that in most cases the best transplant solution for a patient with an incompatible donor is to receive a compatible organ in a KPD.

AREAS OF CONTROVERSY

There has been disagreement about the capacity of KPD to solve the incompatibility problem. However, it is now clear that not all phenotypes will benefit from KPD.

GROWING POINTS

Combining KPD with desensitization greatly expands the boundaries of each of these modalities.

Incompatible kidney transplantation: lessons from a decade of desensitization and paired kidney exchange

Human leukocyte antigen (HLA) sensitization and ABO incompatibility continue to pose significant barriers to further expansion of live donor renal transplantation. However, the recent development of effective desensitization protocols and creative paired donation strategies demonstrates that the presence of circulating donor HLA-specific antibodies and the use of ABO incompatible organs should no longer be considered contraindications for renal transplantation. It is estimated that as many as 6,000 patients on the kidney transplant waiting list have incompatible living donors and could benefit from these treatments. Furthermore, as our understanding of these treatment modalities has improved, it is now possible to predict whether desensitization, kidney paired donation or a combination of both will provide an individual patient with their best chance for successful renal transplantation.

Clinical outcomes of multicenter domino kidney paired donation

Domino kidney paired donation (KPD) is a method by which an altruistic living nondirected donor (LND) is allocated to a pool of incompatible donor-recipient pairs (DRP) and a series of KPDs is initiated. To evaluate the feasibility and clinical outcomes of multicenter domino KPD, we retrospectively analyzed a cohort of DRPs who underwent domino KPD between February 2001 and July 2007 at one of 16 transplant centers. One hundred seventy-nine kidney transplants were performed, with 70 domino chains initiated by altruistic LND. There were 45 two-pair chains, 15 three-pair chains, 7 four-pair chains, 2 five-pair chains and 1 six-pair chain. A majority of donors were spouses (47.5%) or altruistic LNDs (39.1%). DRPs with a blood type O recipient or an AB donor comprised 45.9% of transplanted DRPs. HLA mismatch improved in transplanted donors compared to intended donors in pairs enrolled to improve HLA mismatch (3.4 +/- 0.7 vs. 4.8 +/- 1.0, p < 0.001). One-year and 5-year graft survival rates were 98.3% and 87.7%, respectively, with a median follow-up of 46 months. One-year and 5-year patient survival rates were 97.2% and 90.8%, respectively. In conclusion, multicenter domino KPD could multiply the benefits of donation from LNDs, with patients and graft survival rates comparable to those seen with conventional KPD.

Successful three-way kidney paired donation with cross-country live donor allograft transport

Providing transplantation opportunities for patients with incompatible live donors through kidney paired donation (KPD) is seen as one of the important strategies for easing the crisis in organ availability. It has been estimated that an additional 1000-2000 transplants per year could be accomplished if a national KPD program were implemented in the United States. While most of these transplants could be arranged within the participants' local or regional area, patients with hard-to-match blood types or broad HLA sensitization would benefit from matching across larger geographic areas. In this case, either patients or organs would need to travel in order to obtain maximum benefit from a national program. In this study, we describe how a triple KPD enabled a highly sensitized patient (PRA 96%) to receive a well-matched kidney from a live donor on the opposite coast. The kidney was removed in San Francisco and transported to Baltimore where it was reperfused 8 h later. The patient had prompt function and 1 year later has a serum creatinine of 1.1 mg/dl. This case provides a blueprint for solving some of the complexities that are inherent in the implementation of a national KPD program in a large country like the United States.

Utilization and outcomes of kidney paired donation in the United States

BACKGROUND

Kidney paired donation (KPD) offers the best transplant option for patients with incompatible live kidney donors. Although studies suggest substantial expansion of the donor pool if fully used, few patients in the United States have undergone KPD.

METHODS

We analyzed the 209 KPD and 89 list paired donation (LPD) transplants reported to United Network for Organ Sharing to better understand access to these modalities, clinical outcomes, and areas of potential expansion.

RESULTS

Although many centers offer KPD/LPD, most centers have performed no more than a handful of transplants. As expected, outcomes with KPD/LPD were equivalent to direct donation matched controls. In analyzing current practice, we identified two limitations to KPD in its current use. First, KPD is likely limited now by benefiting mostly patients who are easy to identify and match (such as A donors with B recipients or B donors with A recipients). Second, although some expansion of local KPD availability has reduced travel requirements for patients in those areas, significant room for growth remains.

CONCLUSIONS

Our results suggest that full utilization of KPD would encourage registration of and improve matching for patients who are more difficult to identify and match (such as highly sensitized recipients). Furthermore, expansion of KPD would likely reduce travel requirements and thereby improve access to this treatment modality.

Living kidney organ donation: experiences of spousal support of donors

AIM

The purpose of this study was to explore the process of living kidney donation as experienced by husbands of donors to aid nurses and all members of the health care team in promoting informed consent for those considering living donation and to promote the well being of spouses of living donors, donors and their families.

BACKGROUND

The attitudes of husbands of living kidney donors may affect their decision to donate and satisfaction with recovery from donation surgery, thus it is critical to know how husbands of living kidney donors view kidney donation.

METHODS

Eleven male spouses of living kidney donors were interviewed three months following their wife's donation. Grounded theory methodology was used to inaugurate a substantive theory that describes living kidney donation and its impact on the spousal relationship and family, as experienced by the husband of a donor.

RESULTS

The result of the data analysis was a substantive theory pertaining strictly to the husbands' experiences as the spouse of the living kidney donor. The process commenced with scheduling of the living donation followed by the postoperative time frame, including bringing the donor wife home. The core variable, 'Fulfilling Your Vows', described attitudes, behaviours and actions that guided husbands in successfully and generously caring for their wives, their families, the recipients and themselves throughout the living kidney donation process and continuing 'to this day'.

RELEVANCE TO CLINICAL PRACTICE

The substantive theory of 'Fulfilling Your Vows' will guide nurses and other transplant specialists in helping to improve fully informed consent of potential donors before surgery and in developing supportive strategies to maximize spouse, donor and family outcomes throughout the transplantation process.