Expanded Criteria Donor Kidneys Research Articles

Trends in Usage and Outcomes for Expanded Criteria Donor Kidney Transplantation in the United States Characterized by Kidney Donor Profile Index.

There has been increasing concern in the kidney transplant community about the declining use of expanded criteria donors (ECD) despite improvement in survival and quality of life. The recent introduction of the Kidney Donor Profile Index (KDPI), which provides a more granular characterization of donor quality, was expected to increase utilization of marginal kidneys and decrease the discard rates. However, trends and practice patterns of ECD kidney utilization on a national level based on donor organ quality as per KDPI are not well known. We, therefore, performed a trend analysis of all ECD recipients in the United Network for Organ Sharing (UNOS) registry between 2002 and 2012, after calculating the corresponding KDPI, to enable understanding the trends of usage and outcomes based on the KDPI characterization. High-risk recipient characteristics (diabetes, body mass index ≥30 kg/m2, hypertension, and age ≥60 years) increased over the period of the study (trend test p<0.001 for all). The proportion of ECD transplants increased from 18% in 2003 to a peak of 20.4% in 2008 and then declined thereafter to 17.3% in 2012. Using the KDPI >85% definition, the proportion increased from 9.4% in 2003 to a peak of 12.1% in 2008 and declined to 9.7% in 2012. Overall, although this represents a significant utilization of kidneys with KDPI >85% over time (p<0.001), recent years have seen a decline in usage, probably related to regulations imposed by Centers for Medicare & Medicaid Services (CMS).When comparing the hazards of graft failure by KDPI, ECD kidneys with KDPI >85% have a slightly lower risk of graft failure compared to standard criteria donor (SCD) kidneys with KDPI >85%, with a hazard ratio (HR) of 0.95, a confidence interval (CI) of 0.94-0.96, and statistical significance of p<0.001. This indicates that some SCD kidneys may actually have a lower estimated quality, with a higher Kidney Donor Risk Index (KDRI), than some ECDs. The incidence of delayed graft function (DGF) in ECD recipients has significantly decreased over time from 35.2% in 2003 to 29.6% in 2011 (p=0.007), probably related to better understanding of the donor risk profile along with increased use of hypothermic machine perfusion and pretransplant biopsy to aid in optimal allograft selection.The recent decline in transplantation of KDPI >85% kidneys probably reflects risk-averse transplant center behavior. Whether discard of discordant SCD kidneys with KDPI >85% has contributed to this decline remains to be studied.

Surveillance Registry of Sirolimus Use in Recipients of Kidney Allografts From Expanded Criteria Donors.

The use of expanded criteria donor (ECD) kidneys has increased the overall availability of renal transplants. This study assessed the use of sirolimus in patients receiving Argentina-ECD kidneys. This observational, open-label, 1-arm, prospective, longitudinal pilot study was conducted at 8 transplant centers in Argentina. Adults receiving kidney transplants (without pancreas) from ECDs were eligible if they were converted to sirolimus 1 to 36 months' posttransplantation, with sirolimus becoming base therapy within 1 month after conversion. Patients were followed up for 1 year. Outcomes included reasons for conversion, acute rejection, patient and graft survival, graft status, and safety. The intention-to-treat population included 52 patients (mean age, 48.7 years). Calcineurin inhibitor nephropathy (40%) and chronic allograft nephropathy (25%) were the most frequent reasons for conversion. Two acute rejections occurred during follow-up, but no patients experienced graft loss. One patient died during follow-up, and 3 patients died within 1 month of the last sirolimus dose. Levels of serum creatinine and creatinine clearance remained stable from baseline to week 52/53. Mean proteinuria measured in a subset of patients was 0.2 ± 0.2 g/24 hours before conversion and increased to 0.6 ± 1.2 g/24 hours at week 24/25 and 0.5 ± 0.6 g/24 hours at week 52/53. Adverse events were consistent with those in previous conversion trials; the most common were infections and infestations (54%). This pilot study illustrates the potential benefits of sirolimus in recipients of ECD kidneys in Argentina. Larger, randomized controlled trials are needed to confirm these findings and to clarify the long-term benefits of sirolimus in this patient population.

Does Thymoglobulin Induction Increase Susceptibility to Carbapenem-Resistant Acinetobacter baumannii Sepsis-related Death in Expanded Criteria Donors?

Solid organ transplant recipients are susceptible to antibiotic-resistant infections and carbapenem-resistant Acinetobacter baumannii (CRAB) has recently been recognized as a serious complication in solid organ recipients. High mortality rates have been described. We retrospectively analyzed 807 transplantations and detected 10 patients who died 24 hours after the diagnosis of septicemia, all with CRAB-positive blood cultures. Recipients were followed up for at least 1 year and were stratified into the following groups: Group 1, patients alive; Group 2, patients that died due to other causes except Acinetobacter infection; and Group 3, patients who died within 24 hours of CRAB diagnosis. CRAB-positive patients died a median of 3.17 (range, 1.81-18.7) months after transplantation. In these patients, expanded criteria donors (ECDs) were more frequent (P< .001), as were the use of anti-thymocyte globulin (ATG) induction (P= .02) and delayed graft function (P= .01). For ECD recipients, death rate from any cause, whether induced with ATG or not, was 25% and 20.6%, respectively (odds ratio [OR], 1.28; confidence interval [CI] 95%, 0.56-2.91; P= .68). The death rate from CRAB-related sepsis was 10.3% and 0% whether receiving ATG or not, respectively (OR, 15.49; CI 95%, 0.87-277.16; P= .014). There was a 25.75-fold increase in the death rate in ECD kidney recipients induced with thymoglobulin and with CRAB-related sepsis. Transplants from ECDs and induced with thymoglobulin may be at increased risk of CRAB death in 24 hours when compared with patients with standard donors and induced with thymoglobulin.

Predictors of Deceased Donor Kidney Discard in the United States.

Renal transplantation is a lifesaving intervention for end-stage renal disease. The demand for renal transplantation outweighs the availability of organs; however, up to 20% of recovered kidneys are discarded before transplantation. We aimed to better characterize the risk factors for deceased donor kidney discard. We performed a secondary analysis of the Organ Procurement and Transplantation Network database from 2000 to 2012 of all solid organ donors. The cohort was split into training (80%) and validation (20%) subsets. We performed a stepwise logistic regression to develop a multivariate risk prediction model for kidney graft discard and validated the model. The performance of the models was evaluated with respect to calibration, and area under the curve (AUC) of receiver operating characteristic curves. There were no significant baseline differences between the training (n = 57 474) and validation (n = 14 368) cohorts. The multivariate model validation showed very good discriminant function in predicting kidney discard (AUC = 0.84). Predictors of increased discard included age older than 50 years, performance of a kidney biopsy, cytomegalovirus seropositive status, donation after cardiac death, hepatitis B and C seropositive status, cigarette use, diabetes, hypertension, terminal creatinine greater than 1.5 mg/dL and AB blood type. The model outperformed the Kidney Donor Risk Index in predicting discard (P < 0.001). Subgroup analysis of expanded criteria donor kidneys demonstrated good discrimination with an AUC of 0.70. We have characterized several important predictors of deceased donor kidney discard. Better understanding of factors that lead to increased deceased donor kidney discard can allow for targeted interventions to reduce discard.

Outcomes of kidney transplants and risk of infection transmission from increased infectious risk donors.

Concern over transmission of viral infections has been reported to result in higher discard rates of high infectious risk kidneys (HIR) although data on actual viral transmission rates are lacking. At our center, we performed 89 HIR and 533 non-HIR kidney transplants (KTs) between 2004 and 2011. Follow-up screening labs in recipients of HIR kidneys tested for human immunodeficiency virus, hepatitis C virus, and hepatitis B virus did not reveal any cases of viral transmission over median follow-up of 4.3years. Patient and graft outcomes were similar at 5years between HIR and non-HIR KTs. An updated analysis of the Organ Procurement and Transplant Network (OPTN) registry of deceased-donor kidney transplants between 2008 and 2012 included 57526 transplants was performed. Retrospective calculation of KDRI (kidney donor risk index) differed (P<.001) between all groups with median KDRI of 0.99 for HIR kidneys, 1.07 for non-HIR standard criteria donor kidneys, and 1.81 for non-HIR expanded criteria donor (ECD) kidneys. This was reflected in the significantly improved 5-year graft survival for HIR KTs when compared with non-HIR ECD KTs (84% vs 78%; P<.001). Our data can guide counseling of KT candidates about the safety and benefits of HIR kidneys.

Study of Cadaveric Kidney Transplantation: A Single Center Experience

BackgroundTo increase the number of cadaveric kidney transplants in Japan, it is necessary to proactively perform transplantation from marginal donors. We had the opportunity to frequently perform kidney transplantation from expanded-criteria donors (ECDs), and it is anticipated that there will be increases in the number of ECD kidney transplants. MethodsIn our institution, 18 patients underwent cadaveric kidney transplantation from January 2001 to December 2011. Sixteen of those patients were classified into 2 groups according to donation after brain death (BD) or after cardiac death (CD). We also classified donors as ECDs or standard-criteria donors (SCDs). ResultsKidney graft survival and engraftment were observed in all of the patients. Renal function at 1 year after transplantation was significantly better in the BD group than in the CD group. However, there was no significant difference between the groups in renal function at 3 and 5 years. Renal function at 1 and 3 years after transplantation was significantly better in the SCD group than in the ECD group, but there was no difference in renal function between the SDC and ECD groups at 5 years. ConclusionsThe results were good for all of the patients. There are many reports that graft survival rate at 3–5 years after transplantation from ECDs is poorer than from SCDs. However, no statistically significant difference was found in kidney function at ≥5 years between the ECD and SCD groups in our patients.

Comparison of survival outcomes between Expanded Criteria Donor and Standard Criteria Donor kidney transplant recipients: a systematic review and meta-analysis

In 2002, the United Network for Organ Sharing proposed increasing the pool of donor kidneys to include Expanded Criteria Donor (ECD). Outside the USA, the ECD definition remains the one used without questioning whether such a graft allocation criterion is valid worldwide. We performed a meta-analysis to quantify the differences between ECD and Standard Criteria Donor (SCD) transplants. We paid particular attention to select studies in which the methodology was appropriate and we took into consideration the geographical area. Thirty-two publications were included. Only five studies, all from the USA, reported confounder-adjusted hazard ratios comparing the survival outcomes between ECD and SCD kidney transplant recipients. These five studies confirmed that ECD recipients seemed to have poorer prognosis. From 29 studies reporting appropriate survival curves, we estimated the 5-year pooled nonadjusted survivals for ECD and SCD recipients. The relative differences between the two groups were lower in Europe than in North America, particularly for death-censored graft failure. It is of primary importance to propose appropriate studies for external validation of the ECD criteria in non-US kidney transplant recipients.

Function Based Donor/Recipient Matching in ECD Kidney Transplantation Using the Creatinine Clearance Match Ratio (CCMR)

Expanded criteria donor kidneys (ECD) have the potential to greatly increase the number of kidneys available for transplantation; however utilization is limited by poorer outcomes [1-5]. One strategy to improve outcomes and secondarily utilization is improved matching of kidneys based on recipient factors such as surface area [6,7], kidney graft size to recipient weight [8] and kidney weight to recipient weight [9,10]. Recently our group developed the creatinine clearance match ratio (CCMR) as an improved matching technique. The CCMR is calculated using a manipulation of the Cockcroft-Gault equation estimating the creatinine clearance required by the recipient at a serum creatinine level of 1.0 thereby producing an estimated value for an individual’s creatinine production and in intellectual shorthand, “nephron need” [11,12]. We simply asked; “how much Creatinine clearance would a potential recipient require to achieve a post-transplant serum creatinine of 1.0,” and then created a variable utilizing Cockcroft-Gault estimated donor creatinine clearance from known donor variables. Simplification results in the equation below.

Renal transplantation with expanded criteria donors: Which is the optimal immunosuppression?

The growing gap between demand and supply for kidney transplants has led to renewed interest in the use of expanded criteria donor (ECD) kidneys in an effort to increase the donor pool. Although most studies of ECD kidney transplantation confirm lower allograft survival rates and, generally, worse outcomes than standard criteria donor kidneys, recipients of ECD kidneys generally have improved survival compared with wait-listed dialysis patients, thus encouraging the pursuit of this type of kidney transplantation. The relative benefits of transplantation using kidneys from ECDs are dependent on patient characteristics and the waiting time on dialysis. Because of the increased risk of poor graft function, calcineurin inhibitor (CNI)-induced nephrotoxicity, increased incidence of infections, cardiovascular risk, and malignancies, elderly recipients of an ECD kidney transplant are a special population that requires a tailored immunosuppressive regimen. Recipients of ECD kidneys often are excluded from transplant trials and, therefore, the optimal induction and maintenance immunosuppressive regimen for them is not known. Approaches are largely center specific and based upon expert opinion. Some data suggest that antithymocyte globulin might be the preferred induction agent for elderly recipients of ECD kidneys. Maintenance regimens that spare CNIs have been advocated, especially for older recipients of ECD kidneys. CNI-free regimens are not universally accepted due to occasionally high rejection rates. However, reduced CNI exposure and CNI-free regimens based on mammalian target of rapamycin inhibitors have shown acceptable outcomes in appropriately selected ECD transplant recipients.

Deceased Donor Kidney Transplantation in Patients Aged 70 and Older: Is 70 the New 50?

Background: Deceased donor (DD) kidney transplantation (KT) outcomes in patients who are aged 70 years and older are understudied. Methods: We retrospectively reviewed our single center DD KT outcomes in patients aged 70 years and older. All patients received antibody induction with tacrolimus, half-dose mycophenolate, ± steroids. Results: Over 10.75 years, we performed 114 KTs in 112 patients aged 70 and older (mean 73.8, range 70-84 years) including 42 patients who were aged 75 and older. The study group included 60 males/52 females and 79 Caucasians/28 African Americans/5 other with a mean waiting time of 16 months; 75 patients (66%) received kidneys from expanded criteria donors (ECDs) and 14 received dual KTs. Delayed graft function occurred in 27% and influenced graft but not patient survival. With a mean follow-up of 68 months, patient survival was 59% and uncensored kidney graft survival was 47%. Three year and death-censored kidney graft survival rates were 76% and 74%, respectively. Outcomes were similar in patients < or ≥ 75 years. Of 60 graft losses, death with a functioning graft (DWFG) accounted for 41 (68%). Of 46 deaths, 72% were due to cardio/cerebrovascular events, infection, or malignancy. At present, 54 of the 66 surviving patients (81.8%) have functioning grafts. The incidences of acute rejection and major infection were 14% and 45%, respectively. Conclusions: Advanced recipient age has a modest effect on medium-term outcomes in appropriately selected elderly patients using predominantly ECD kidneys, which may not be appropriate for younger patients. However, medium-term outcomes are largely influenced by a higher incidence of DWFGs in the elderly, suggesting that matching strategies for kidney and patient longevity are warranted.

Impact of Early Low-Grade Proteinuria and Allograft Dysfunction on Survival in Expanded Criteria Donor Kidney Transplant Recipients

IntroductionRecent studies have demonstrated a relationship between low-grade proteinuria and worse graft survival, but this has not been fully studied in expanded criteria donor (ECD) kidney transplant recipients. AimThe aim of this study was to assess whether the combination of early low-grade proteinuria (<1 g/d) and allograft dysfunction at the third month post-transplantation predicts outcomes in terms of survival in ECD kidney transplant recipients. Material and MethodsWe studied a cohort of 269 ECD kidney transplant recipients subdivided into 4 groups according to clinically relevant proteinuria (300 mg/d) and median creatinine (Cr; 1.7 mg/dL; interquartile range, 1.4–2.1 mg/dL) at the third month post-transplantation: Group A (Cr <1.7 mg/dL and proteinuria <300 mg/24 h; n = 97), Group B (Cr <1.7 mg/dL and proteinuria ≥300 mg/24 h; n = 38), Group C (Cr ≥1.7 mg/dL and proteinuria <300 mg/24 h; n = 79), and Group D (Cr ≥1.7 mg/dL and proteinuria ≥300 mg/24 h; n = 55). ResultsDeath-censored graft survival was significantly lower in Group D compared with the rest (P < .007). Multivariate Cox regression analysis using fixed covariates showed that the combination of low-grade proteinuria and a lower estimated glomerular filtration rate (eGFR) as associated with graft failure (hazard rate [HR] 2.5, 95% confidence interval [CI], 1.09–5.97; P = .03). ConclusionsThe early association of low-grade proteinuria and allograft dysfunction represents an important risk factor for graft loss in ECD kidney transplant recipients. Strategies to optimize renal function could improve the outcome in this specific population.

Do elderly recipients really benefit from kidney transplantation?

Data from the nineties showed that even older individuals had a survival advantage with kidney transplantation compared to dialysis. Consequently, we are increasingly wait-listing high-risk patients in terms of age and co-morbidities. However, times are changing. Due to severe organ shortage we now use more often expanded criteria donor kidneys with less favorable outcomes, while at the same time survival on dialysis is improving. The question therefore rises again if elderly patients really benefit from transplantation nowadays. At least for the U.S., recent data still suggest an overall survival benefit with transplantation in older recipients but the risks vary greatly with the health status of the recipient and with the type of donor. Especially for transplant centers outside of the U.S., recent large studies are lacking. Because of continuing changes in both donor and recipient characteristics as well as dialysis outcomes, a permanent area-specific reassessment of data is needed. In this review we describe the important evolutions in transplant and dialysis care over the last 20 years and provide an overview on recent data comparing survival on dialysis versus transplantation in the elderly.

Results of Expanded-Criteria Donor Kidneys: A Single-Center Experience in Hungary

BackgroundTo ease organ shortage, many transplant centers accept kidneys from expanded-criteria donors (ECDs). Our aim was to analyze the results of ECD grafts in our center. MethodsData on cadaveric donors were retrospectively analyzed between January 2011 and September 2014. Definition of ECD was: (1) donor age ≥60 years, (2) donor age 50 to 59 years, and (3) the presence of 2 among the following criteria: hypertension, serum creatinine >1.5 mg/dL, or death from cerebrovascular accident. Standard-criteria donors (SCDs) were those who did not meet the criteria for an ECD. ResultsDuring the observation period, 215 cadaveric donors were reported within our region, and 14 kidneys were offered to our center from Eurotransplant. Ninety-one (40%) among the reported donors were ECDs and 123 (54%) were SCDs. The rates of delayed graft function (DGF) and acute rejection (ARE) were not influenced by transplantation of an ECD graft. The cumulative patient and graft survival rates for ECDs were comparable with those of patients who received an optimal graft. ConclusionsECD grafts can be transplanted safely, without the increased risk of DGF, ARE, and inferior patient and graft survival, in the case of careful patient allocation, and with the use of induction therapy.

A Lifetime of Allograft Function with Kidneys from Older Donors.

Strategies to increase expanded criteria donor (ECD) transplantation are needed. We quantified the extent to which ECD kidneys provide recipients with a lifetime of allograft function by determining the difference between patient survival and death-censored allograft survival (graft survival). Initial analyses compared 5-year outcomes in the Eurotransplant Senior Program (European) and the United States Renal Data System. Among European recipients ≥65 years, patient survival exceeded graft survival, and ECD recipients returned to dialysis for an average of 5.2 months after transplant failure. Among United States recipients ≥60 years, graft survival exceeded patient survival. Although patient survival in elderly recipients in the United States was low (49% at 5 years), the average difference in patient survival at 10 years in elderly recipients in the United States with an ECD versus non-ECD transplant was only 7 months. The probability of patient survival with a functioning allograft at 5 years was higher with ECD transplantation within 1 year after activation to the waiting list than with delayed non-ECD transplantation ≥3 years after activation to the waiting list. Subsequent analyses demonstrated that ECD transplants do not provide a lifetime of allograft function in recipients <50 years in the United States. These findings should encourage ECD transplantation in patients ≥60 years, demonstrate that rapid ECD transplantation is superior to delayed non-ECD transplantation, and challenge the policy in the United States of allowing patients <50 years to receive an ECD transplant.

Can only histological evaluation determine the allocation of ECD kidneys?

IntroductionThere is a recent debate on the "transplantability" of ECD (Expanded Criteria Donors) kidneys and the selection criteria used to allocate them to single or double transplantation. Remuzzi et al. have defined a protocol incorporating pre-transplant donor biopsy to guide the use of older donor organs. They allocated organs as single or double transplants on the basis of histological findings. We aim to show the pros and cons of the only histological evaluation in the allocation of ECD kidneys, to compare the different experiences in United States and Europe and thus to discuss whether this tool should be used alone or included in a comprehensive clinical and histopathological evaluation.DiscussionIn the United States many Authors stated that the biopsy actually increases the percentage of kidney discarded and they raised questions about the importance of the biopsy in evaluating ECD kidneys for transplantation. On the other hand, the experiences of the majority of european transplant centers showed that allocating kidneys as single or dual transplant based on biopsy findings may achieve good graft and patient outcomes.Moreover, the experience of some centers as ours showed that kidneys allocated as DKT (Dual Kidney Transplant) on the basis of Remuzzi’s score could have been suitable for single transplantation suggesting the need of an adjustment of the Remuzzi Score System. Many Authors, who are in favor of histological evaluation, actually believe that a comprehensive clinical and histopathological assessment before transplantation remains necessary.SummaryWe lack precise national- or international-based selection criteria to guide clinicians. An adjustment of the Remuzzi Score System could be taken into consideration such as narrowing the indication for DKT from those ECD kidneys with higher scores and including the histological evaluation in a multifactor score.

Pretransplant Biopsy in Expanded Criteria Donors: Do We Really Need It?

IntroductionRenal transplantation is the best treatment for end-stage renal disease, including when using expanded criteria donors (ECD) kidneys. However, these suboptimal kidneys should be evaluated rigorously to meet their usefulness. Opinions differ about the best way to evaluate them. Materials and MethodsWe retrospectively reviewed kidneys from ECD harvested by a single academic institution between January 2008 and September 2013. Needle biopsies were performed at the time of the harvest when considered relevant by the transplant team. Two pathologists where responsible for their analysis; the Remuzzi classification has been used in all cases. ResultsWe evaluated 560 ECD kidneys. Biopsies were made in 197 (35.2%) organs, 20 of which were considered not usable and 36 good only for double transplantation. Sixty-three kidneys (11.3%) were discarded by the transplant team based on the biopsy result and clinical criteria. Donors who underwent a biopsy were older (P < .001) and had a worse glomerular filtration rate (GFR; P = .001). Comparing donors approved and rejected by the biopsy, the rejected donors were heavier (P = .003) and had a lower GFR (P = .002). Cold ischemia time was longer for the biopsy group (P < .001). Regarding graft function, the biopsy overall score correlated with the transplant outcome in the short and long term. Separately, glomeruli and interstitium scores were correlated with recipient's GFR in the earlier periods (3 months; P = .025 and .037), and the arteries and tubules correlated with GFR in the longer term (at 3 years P = .004 and .010). ConclusionThe decision on the usability of ECD grafts is complex. At our center, we chose a mixed approach based on donor risk. Low-risk ECD do not require biopsy. In more complex situations, especially older donors or those with a lower GFR, prompted a pretransplant biopsy. The biopsy results proved to be useful as they relate to subsequent transplant outcomes, thereby allowing us to exclude grafts whose function would most probably be less than optimal.

Proposal of Categorization of Expanded Criteria Donors in Renal Transplantation

IntroductionTransplantation of renal allografts that have been procured from expanded criteria donors (ECD) have prevailed in an attempt to expand the donor pool. Even though ECD is an acceptable source of donors, the wide range of age along with the presence or not of risk factors necessitates further categorization. The aim of this study was to analyze the allograft and recipient survival of the ECD renal grafts and to propose an ECD categorization model. Patients and MethodsWe reviewed the medical records of renal transplant recipients from January 2002 to July 2012, who received renal allografts from expanded and standard criteria donors (SCD) without risk factors such as hypertension, cerebrovascular disease or impaired renal function. ResultsDuring the study period, 310 renal transplantations were performed in our Transplant Unit, of which 86 and 114 renal grafts were procured from ECD and SCD respectively. ECD renal graft survival the first, third and fifth year was 92%, 82% and 70% while respective recipient survival was 95%, 87% and 82%. Comparison with the control group of SCD showed that ECD renal graft survival after the third post-transplant year was significantly inferior (P < .0001). Donor age was a considerable prognostic factor of long-term renal graft function. Serum creatinine of ECD grafts was the first and third year 1.86 ± 0.6 mg/dL and 1.91 ± 0.8 mg/dL, respectively, showing significant difference to that of SCD grafts (P < .0001). Further categorization of ECD showed that renal allografts procured from donors above 60 years old without risk factors had better renal graft survival and function compared to grafts procured from donors aged 50–59 with 2 or 3 risk factors. ConclusionsRenal transplantation from ECD offers acceptable graft survival rates, however they are inferior compared to renal grafts from optimal kidney donors. ECD kidney grafts have to be categorized, taking into consideration the independent risk factors.

Validation of the Maryland Aggregate Pathology Index (MAPI), a pre-implantation scoring system that predicts graft outcome.

Predicting graft outcome after renal transplantation based on donor histological features has remained elusive and is subject to institutional variability. We have shown in a retrospective study that the Maryland Aggregate Pathology Index score reliably predicts graft outcome. We sought to validate the scoring system in our center and a second transplant center. We analyzed 140 deceased donor kidneys pre-implantation biopsies from center 1 and 65 from center 2. The patients had a mean follow-up of 695 ± 424 and 656 ± 305 d respectively. Although MAPI scores were similar, there were significant differences in donor and recipient parameters between both centers. Despite this, MAPI was predictive of graft outcome for both centers by Cox univariate, multivariate and time dependent ROC analysis. For center 1 and 2, three yr graft survival within each MAPI group was statistically equivalent. The three-yr graft survival at center 1 for low, intermediate, and high MAPI groups were 84.3%, 56.5%, and 50.0%, respectively, p ≤ 0.0001, and at center 2 were 83.3%, 33.3%, and 33.3%, p = 0.006. MAPI, which is based on a pre-implantation biopsy, demonstrated similar predictive and outcome results from both centers. As expanded criteria donors (ECD) criteria have redefined marginal kidneys, MAPI has the potential to further define ECD kidneys, increase utilization, and ultimately improve outcomes.

Matching “Engine and Chassis” in ECD Kidney Transplantation Using a Novel Creatinine Clearance Match Ratio (CCMR) Is Associated With Improved Outcomes.

BACKGROUND: To improve outcomes of expanded criteria donor (ECD) kidneys, prior studies matched donors to recipients according to recipient weight or donor kidney size. This study hypothesizes that matching donors to recipients based on Cockcroft-Gault estimates of creatinine clearance can improve outcomes in ECD kidney transplants compared to predictions based on size matching or donor creatinine clearance alone. METHODS: Recipients of ECD kidneys in the Scientific Registry of Transplant Recipients (SRTR) who were transplanted from October 1, 1987 to August 31, 2011 were included. The estimated creatinine clearance ratio (CCMR) was calculated as the estimated recipient creatinine clearance based on manipulations of the Cockcroft-Gault equation utilizing donor creatinine clearance at the time of transplant. Univariate and multivariate analyses predicted the hazard ratio of graft failure and the odds ratio of requiring dialysis within the first week. The CCMR was compared to the kidney donor risk index (KDRI) and recipient-to-donor weight and age ratios using discrimination analyses. RESULTS: 25,640 ECD kidney transplants were analyzed. On multivariate analysis, higher CCMR was associated with increased graft failure and odds of requiring dialysis within the first week (comparing highest ratio quintile versus lowest ratio quintile: HR 1.53, p<0.001; OR 2.18, p<0.001). CCMR was found to be superior in prediction and discrimination ability as compared to donor creatinine clearance, recipient/donor age ratio, and recipient/donor weight ratio. CONCLUSION: ECD kidneys have improved outcomes when the donor/recipient creatinine clearance match ratio is optimal.

Recipients of ECD and SCD Kidney From the Donors Age 50-59 Have Comparable Outcomes: A Matched Pair Analysis.

Background: Both donor and recipient characteristics play a role in kidney transplant (tx) outcome. Using a large database to look at risks, the SRTR defined an expanded criteria donor (ECD) as one whose kidneys are associated with ≥ 1.7 risk of graft failure versus a standard criteria donor (SCD). Because of the worse results, use of kidneys from donors meeting ECD criteria has been limited. It is unclear whether worse outcomes are due to: a) worse kidney function at the time of tx, b) more rapid decline in renal function over time; and/or c) recipient characteristics. We compared outcomes of 49 recipients of ECD kidneys from donors 50-59 vs. 66 matched recipients of SCD kidneys (from donors 50-59). Recipients were matched on age at transplant, gender, date of transplant, type 1 diabetes prior the transplant, and primary versus retransplant. We compared eGFR levels at 1 and 12 months, slope of 1/Cr vs time in the first year, and separately, after the 1st year posttransplant. Results: There were no differences in demographics between the 2 groups except in race (ECD: 86% C, 0%AA, 4% other; SCD: 85%C, 0%AA, 14% other). Mean ECD recipient age was 50±14 years; SCD, 51±14 years (NS). Patient survival, graft survival, and death censored graft survival were not different between groups ( table 1).Table: No Caption available.Mean eGFR at 1 month was 41.3±19.6 for ECD and 37.2±14ml/min/1.73m2 for SCD; at 12 months was 43.1±17.9 for ECD and 36.4±15.8 ml/min/1.73 m2 for SCD (NS). Slope of 1/Cr vs time did not differ between ECD and SCD within first year; similarly, there was no difference after the 1st yr (table2).Table: No Caption available.Conclusion: ECD transplants from donors 50-59 (at least as selected at our institution), compared to recipient-matched SCD tx, have similar 1-yr intercept and similar post 1-yr slope of 1/Cr vs time. In matched recipients, ECD tx with 1 yr survival are associated with equivalent 60 month slopes of 1/Cr vs time as SCDs.