Dual-kidney transplantation with organs from expanded criteria donors: a long-term follow-up

Outcomes of Dual Kidney Transplants from High KDPI Kidneys are Superior Compared to Single Kidney High KDPI Transplants at One-Year

Dual kidney transplantation (DKT), utilizing two adult kidneys from the same donor for one recipient, has been used as way to expand the available donor pool. These kidneys often come from high Kidney Donor Profile Index donors (KDPI >85%). Data comparing outcomes between high KDPI DKT and single kidney transplants (SKT) remain limited. We assessed outcomes of 336 high KDPI kidney transplants performed at our center; 11.0% (n = 37) were DKT. Recipients of DKT were older (p = 0.02) and donors had a higher KDPI score (median 96% vs. 91%, p<0.0001). DKT operative time was higher compared to SKT (+1.4 hours, p<0.0001). There were no differences in delayed graft function (54.1% vs. 51.5%, p = 0.77) and hospital length of stay (median 4.0 vs. 3.0 days, p = 0.21) between DKT and SKT. Grade I Clavien-Dindo complications occurred in 8.1% of DKT and 13.7% of SKT (p = 0.008). There were no grade IVa, IVb or V complications in either group. DKT had more glomerulosclerosis (p = 0.04), interstitial fibrosis (p = 0.02), tubular atrophy (p = 0.01), and arterial thickening (p = 0.03) on one-year protocol biopsies. Estimated glomerular filtration was higher for DKT at one- (p = 0.004) and two-years post-transplant (p = 0.01). There were no differences in patient (HR 1.3, 95% CI 0.5-3.3, p = 0.58) or graft (HR 1.1, 95% CI 0.5-2.3, p = 0.83) survival. Good outcomes can be achieved with DKT using high KDPI kidneys with moderate chronic changes. DKT is a good option to help further utilize high KDPI kidneys and minimize discard. This article is protected by copyright. All rights reserved.

Dual kidney transplants from adult marginal donors: Review and perspective

The practice of dual kidney transplantation (DKT) from adult marginal deceased donors (MDDs) dates back to the mid-1990s with initial pioneering experiences reported by the Stanford and Maryland groups, at which time the primary indication was estimated insufficient nephron mass from older donors. Multiple subsequent studies of short and long-term success have been reported focusing on three major aspects of DKT: Identifying appropriate selection criteria and developing scoring systems based on pre- and post-donation factors; refining technical aspects; and analyzing mid-term outcomes. The number of adult DKTs performed in the United States has declined in the past decade and only about 60 are performed annually. For adult deceased donor kidneys meeting double allocation criteria, >60% are ultimately not transplanted. Deceased donors with limited renal functional capacity represent a large proportion of potential kidneys doomed to either discard or non-recovery. However, DKT may reduce organ discard and optimize the use of kidneys from MDDs. In an attempt to promote utilization of MDD kidneys, the United Network for Organ Sharing introduced new allocation guidelines pursuant to DKT in 2019. The purpose of this review is to chronicle the history of DKT and identify opportunities to improve utilization of MDD kidneys through DKT. This article is protected by copyright. All rights reserved.

Long-term survival benefit from dual kidney transplantation using kidneys from donors with very extended criteria - A French cohort between 2002 and 2014

BACKGROUND

This national multicenter retrospective cohort study aimed to assess the long-term outcomes of dual kidney transplantation (DKT) and compare them with those obtained from single kidney transplantation (SKT).

METHODS

Our first analysis concerned all first transplants performed between May 2002 and December 2014, from marginal donors, defined as brain death donors older than 65, with an estimated glomerular filtration rate (eGFR) lower than 90 ml/min/1.73m². The second analysis was restricted to transplants adequately allocated according to the French DKT program based on donor eGFR: DKT for eGFR between 30 and 60, SKT for eGFR between 60 and 90 ml/min/1.73m². Recipients younger than 65 years or with a panel-reactive antibody percentage ≥ 25% were excluded.

RESULTS

The first analysis included 461 DKT and 1131 SKT. DKT donors were significantly older (77.6 versus 74 years), had a more frequent history of hypertension and a lower eGFR (55.1 versus 63.6 ml/min/1.73m²). While primary nonfunction and delayed graft function did not differ between SKT and DKT, 1-year eGFR was lower in SKT recipients (39 vs. 49 ml/min/1.73m², P < 0.001). Graft survival was significantly better in DKT, even after adjustment for recipient and donor risk factors. Nevertheless, patient survival did not differ between these groups. The second analysis included 293 DKT and 687 SKT adequately allocated with donor eGFR and displayed similar results but with a smaller benefit in terms of graft survival.

CONCLUSIONS

In a context of organ shortage, DKT is a good option for optimizing the use of kidneys from very expanded criteria donors.

Dual Kidney Transplantation from Donors at the Extremes of Age

BACKGROUND

The study purpose was to analyze outcomes in recipients of pediatric dual en bloc (PEB) kidneys from small pediatric donors (SPDs, age ≤ 3 years) and dual kidney transplants (KTs) from adult marginal deceased donors (DDs) in the context of the Kidney Donor Profile Index (KDPI).

STUDY DESIGN

This was a single center retrospective review. Recipient selection included primary transplant, low BMI, low immunologic risk, and informed consent. All patients received antibody induction with FK/MPA/± prednisone.

RESULTS

From 2002 to 2015, we performed 34 PEB and 73 adult dual KTs. Mean donor ages were 17 months for the PEB and 59 years for the dual KTs; mean KDPIs were 73% for PEB and 83% for dual KT, and mean cold ischemia times were 21.0 hours for PEB and 26.5 hours for dual KT. Adult dual KT recipients were older (mean age 38 years for PEB and 60 years for dual KT) and had shorter waiting times (mean 25 months for PEB and 12 months for dual KT). With a mean follow-up of 7.6 years, actual patient survival (88% for PEB and 62% for dual KT) and graft survival (71% for PEB and 44% for dual KT) rates were higher in PEB compared with dual KT. Death-censored kidney graft survival rates were 77% for PEB and 58% for dual KT. Delayed graft function (DGF) rates were 15% for PEB and 23% for dual KT; incidences of DGF in single kidney transplantations from SPDs and adult nonmarginal DDs were 20% and 32%, respectively. Based on actual 5-year graft survival rates, the adjusted KDPIs for dual PEB and dual KTs were 3% and 60%, respectively.

CONCLUSIONS

Acceptable mid-term outcomes are associated with PEB and adult dual KTs, which may expand the donor pool and prevent kidney discard. The KDPI is inaccurate for predicting outcomes from either PEB from SPDs or dual KT from adult marginal DDs, which may prevent acceptance of these organs.

Dual Kidney Transplantation: A Review of Past and Prospect for Future

Kidney transplantation (KT) is one of the treatment options for patients with chronic kidney disease. The number of patients waiting for kidney transplantation is growing day by day. Various strategies have been put in place to expand the donor pool. Extended criteria donors are now accepted more frequently. Increasing number of elderly donors with age > 60 years, history of diabetes or hypertension, and clinical proteinuria are accepted as donor. Dual kidney transplantation (DKT) is also more frequently done and experience with this technique is slowly building up. DKT not only helps to reduce the number of patients on waiting list but also limits unnecessary discard of viable organs. Surgical complications of DKT are comparable to single kidney transplantation (SKT). Patient and graft survivals are also promising. This review article provides a summary of evidence available in the literature.

Dual kidney transplants from adult marginal donors successfully expand the limited deceased donor organ pool

BACKGROUND

The need to expand the organ donor pool remains a formidable challenge in kidney transplantation (KT). The use of expanded criteria donors (ECDs) represents one approach, but kidney discard rates are high because of concerns regarding overall quality. Dual KT (DKT) may reduce organ discard and optimize the use of kidneys from marginal donors.

STUDY DESIGN

We conducted a single-center retrospective review of outcomes in adult recipients of DKTs from adult marginal deceased donors (DD) defined by limited renal functional capacity. If the calculated creatinine clearance in an adult DD was <65 mL/min, then the kidneys were transplanted as a DKT.

RESULTS

Over 11.5 yr, 72 DKTS were performed including 45 from ECDs, 17 from donation after cardiac death (DCD) donors, and 10 from standard criteria donors (SCD). Mean adult DD and recipient ages were both 60 yr, including 29 DDs and 26 recipients ≥65 yr of age. Mean pre-DKT waiting and dialysis vintage times were 12 months and 25 months, respectively. Actual patient and graft survival rates were 84.7% and 70.8%, respectively, with a mean follow-up of 58 months. One yr and death-censored graft survival rates were 90% and 80%, respectively. Outcomes did not differ by DD category, recipient age, or presence of delayed graft function (DGF). Eleven patients died at a mean of 32 months post-DKT (eight with functioning grafts) and 13 other patients experienced graft losses at a mean of 33 months. The incidence of DGF was 25%; there were two cases (2.8%) of primary non-function. Mean length of initial hospital stay was 7.2 d. Mean serum creatinine and glomerular filtration rate levels at 12 and 24 months were 1.5 and 53 and 1.5 mg/dL and 51 mL/min/1.73 m(2) , respectively. DKT graft survival and function were superior to concurrent single ECD and similar to concurrent SCD KTs. Two patients underwent successful kidney retransplantation, so the dialysis-free rate in surviving patients was 87%. The proportion of total renal function transplanted from adult DD to DKT recipients was 77% compared to 56% for patients receiving single KTs.

CONCLUSIONS

Dual kidney transplantation using kidneys from adult marginal DDs that otherwise might be discarded offer a viable option to counteract the growing shortage of acceptable single kidneys. Excellent medium-term outcomes can be achieved and waiting times can be reduced in a predominantly older recipient population.

Dual kidney transplantation involving organs from expanded criteria donors: a review of our series and an update on current indications

BACKGROUND

Our purpose was to review our kidney transplantation program based on the use of expanded criteria donors, and to determine current indications for dual kidney transplantation (DKT). In 1996, a program was initiated to transplant kidneys from donors of over 60 years performing single or dual transplantation.

METHODS

In 1996, a program was initiated to transplant kidneys from donors of over 60 years performing single or dual transplantation. DKT were performed with donors >75 and donors between 60 and 74 years of age and glomerulosclerosis of >15%. The kidneys of donors between 60 and 74 years of age and with glomerulosclerosis of <15% were used for single kidney transplantation (SKT). In 2005, we started to perform SKT despite glomerulosclerosis being >15%, taking into account donor and recipient characteristics.

RESULTS

From 1996 to 2004, 222 SKTs and 88 DKTs were performed. Graft survival after 1 and 4 years was, respectively, 91% and 78% for SKT and 95% and 79% for DKT. In 2005, we started to perform SKT despite glomerulosclerosis being >15%, taking into account donor and recipient characteristics. From 2005 to 2011, 328 SKT and 32 DKT were performed. During this period most kidneys used for DKT were from female donors >75 years old, weighing <65 kg, with a creatinine of >1 mg/dL and glomerulosclerosis of >15%. The recipients for DKT were mostly male, <70 years old and whose weight was >75 kg.

CONCLUSION

DKT from expanded criteria donors shows good outcomes. However, in many cases SKT may fulfill the need of the recipient. The archetype for DKT is an older female weighing <65 kg and the most common recipient is an overweight male who is <70 years old.

Can only histological evaluation determine the allocation of ECD kidneys?

INTRODUCTION

There 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.

DISCUSSION

In 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. We 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.

The Kidney Donor Profile Index (KDPI) of marginal donors allocated by standardized pretransplant donor biopsy assessment: distribution and association with graft outcomes

Pretransplant donor biopsy (PTDB)-based marginal donor allocation systems to single or dual renal transplantation could increase the use of organs with Kidney Donor Profile Index (KDPI) in the highest range (e.g. >80 or >90), whose discard rate approximates 50% in the United States. To test this hypothesis, we retrospectively calculated the KDPI and analyzed the outcomes of 442 marginal kidney transplants (340 single transplants: 278 with a PTDB Remuzzi score<4 [median KDPI: 87; interquartile range (IQR): 78-94] and 62 with a score=4 [median KDPI: 87; IQR: 76-93]; 102 dual transplants [median KDPI: 93; IQR: 86-96]) and 248 single standard transplant controls (median KDPI: 36; IQR: 18-51). PTDB-based allocation of marginal grafts led to a limited discard rate of 15% for kidneys with KDPI of 80-90 and of 37% for kidneys with a KDPI of 91-100. Although 1-year estimated GFRs were significantly lower in recipients of marginal kidneys (-9.3, -17.9 and -18.8 mL/min, for dual transplants, single kidneys with PTDB score<4 and =4, respectively; p<0.001), graft survival (median follow-up 3.3 years) was similar between marginal and standard kidney transplants (hazard ratio: 1.20 [95% confidence interval: 0.80-1.79; p=0.38]). In conclusion, PTDB-based allocation allows the safe transplantation of kidneys with KDPI in the highest range that may otherwise be discarded.

Dual kidney transplant: a single-center experience and review of the literature

OBJECTIVES

Adult dual kidney transplant is a strategy to overcome the imbalance between limited nephron mass supplied from an older donor and a recipient with a metabolic request.

MATERIALS AND METHODS

In our report, we review the literature and present our single-center experience. From June 2007 until July 2012, nine hundred twenty-eight single and seventeen dual kidney transplants from deceased donors were performed.

RESULTS

The average donor was 71.5 ± 3.6 years of age with an average serum creatinine, creatinine clearance, and an average number of sclerotic glomeruli, 106.1 ± 44.2 μmol/L, 0.97 ± 0.37 mL/s, and 22.4 ± 14.2. Immediate graft function and acute rejection episodes were observed in 75% and 6% of patients. The overall patient survival rates at 1 and 2 years after transplant were 93%. The overall graft survival rates at 1 and 2 years were 88%.

CONCLUSIONS

Previous studies and our single-center experience suggest that the dual transplant procedure may help improve results of kidney transplants from expanded criteria donors and extend the donor pool by using kidneys that would be discarded otherwise.

Kidneys at higher risk of discard: expanding the role of dual kidney transplantation

Half of the recovered expanded criteria donor (ECD) kidneys are discarded in the United States. A new kidney allocation system offers kidneys at higher risk of discard, Kidney Donor Profile Index (KDPI)>85%, to a wider geographic area to promote broader sharing and expedite utilization. Dual kidney transplantation (DKT) based on the KDPI is a potential option to streamline allocation of kidneys which otherwise would have been discarded. To assess the clinical utility of the KDPI in kidneys at higher risk of discard, we analyzed the OPTN/UNOS Registry that included the deceased donor kidneys recovered between 2002 and 2012. The primary outcomes were allograft survival, patient survival and discard rate based on different KDPI categories (<80%, 80-90% and >90%). Kidneys with KDPI>90% were associated with increased odds of discard (OR=1.99, 95% CI 1.74-2.29) compared to ones with KDPI<80%. DKTs of KDPI>90% were associated with lower overall allograft failure (HR=0.74, 95% CI 0.62-0.89) and better patient survival (HR=0.79, 95% CI 0.64-0.98) compared to single ECD kidneys with KDPI>90%. Kidneys at higher risk of discard may be offered in the up-front allocation system as a DKT. Further modeling and simulation studies are required to determine a reasonable KDPI cutoff percentile.

Outcomes of adult dual kidney transplants by KDRI in the United States

UNOS guidelines provide inadequate discriminatory criteria for kidneys that should be transplanted as single (SKT) versus dual (DKT). We evaluated the utility of the kidney donor risk index (KDRI) to define kidneys with better outcomes when transplanted as dual. Using SRTR data from 1995 to 2010 of de novo KTX recipients of adult deceased-donor kidneys, we examined outcomes of SKT and DKT stratified by KDRI group ≤1.4 (n = 49 294), 1.41-1.8 (n = 15 674), 1.81-2.2 (n = 6523) and >2.2 (n = 2791). DKT of kidneys with KDRI >2.2 was associated with significantly better overall graft survival [adjusted hazard ratio (aHR) 0.83, 95% confidence interval (CI) 0.72-0.96] compared to single kidneys with KDRI >2.2. DKT was associated with significantly decreased odds of delayed graft function (top 2 KDRI categories) and significantly decreased odds of 1-year serum creatinine level >2 mg/dL (top 3 KDRI categories). Among SKT and DKT from KDRI >2.2 there were 16.1 and 13.9 graft losses per 100 patient follow-up years, respectively. KDRI >2.2 is a useful discriminatory cut-off for the determination of graft survival benefit with the use of DKT; however, the benefit of increased graft years was less than half of single kidneys from donors in the same KDRI range.

Dual kidney transplantation from uncontrolled deceased donors after cardiac arrest: a possible option

Organ shortage is a major problem in organ transplantation. For this reason, transplantation teams have found it necessary to revisit their organ acceptance criteria. Uncontrolled deceased donors after cardiac arrest could increase the donor pool by 20%, but at the same time there is a greater risk of delayed graft function and primary non-function. Dual kidney transplantation is an option when single kidney transplantation cannot be carried out because of lack of organ quality. We report for the first time our four first dual kidney transplantation from uncontrolled deceased donors after cardiac arrest with a follow up longer than 1 year. We described graft outcomes until 5 years, and histology at 3 and 12 months after transplantation. All organs were machine perfused in order to assess their quality leading to a single kidney transplantation or dual kidney transplantation decision. After 1 year of follow up, all grafts were functional with a mean estimated glomerular filtration rate of 44.5 ± 3.3 mL/min/1.73 m(2), and a mean inulin clearance of 43.7 ± 13.6 mL/mn/1.73 m(2). These findings suggest that dual kidney transplantation can represent a viable option for kidneys unsuitable for single kidney transplantation without increasing the rate of surgical complications. Successful transplantation is linked to histological, biological and donor clinical criteria, as well as perfusion parameters.

Adult dual kidney transplantations obtained from marginal donors: two case reports

Organ shortage has led us to use grafts from expanded criteria donors (ECD). Dual kidney transplantation (DKT) using organs from an ECD, which are not acceptable for single kidney transplantation (KT), may overcome the insufficient functioning nephron mass. We performed DKTs in two recipients, the first DKT to be reported from Korea. In case 1, the donor was a 36-year-old man with hypertension. The cause of his brain death was intracranial hemorrhage. He had no known underlying renal disease; his serum creatinine level was 4.2 mg/dL. Despite the relatively young age of the donor, a biopsy revealed mild interstitial fibrosis and tubular atrophy with moderate arteriolar narrowing. The recipient's postoperative course was uneventful over the 69-month follow-up; her last serum creatinine was 1.3 mg/dL. In case 2, the 80-year-old male donor with a history of hypertension had a normal creatinine. The donor biopsy revealed mild glomerular sclerosis, tubular atrophy, and interstitial fibrosis with moderate arteriolar narrowing. The recipient had undergone a previous KT 14 years previously on the right side of the abdomen, but had resumed dialysis 2 years previously due to chronic allograft nephropathy. There was no delayed graft function. At month 4 posttransplantation, lymphoceles were treated by fenestration. At 6-month follow-up, her creatinine was 1.0 mg/dL. In our experience with these two cases, DKT with ECD kidney grafts seemed to be a successful strategy to avoid poor graft outcomes and overcome the donor organ shortage. Further studies including histological criteria for DKT, should be performed to determine the safest means to utilize ECD grafts.

Use of two expanded-criteria-donor renal allografts in a single patient

The disparity between the number of available renal donors and the number of patients on the transplant waiting list has prompted the use of expanded-criteria-donor (ECD) renal allografts to expand the donor pool. ECD allografts have shown good results in appropriately selected recipients, yet a number of renal allografts are still discarded. The use of dual renal transplantation may lower the discard rate. Additionally, the use of perfusion systems may improve acute tubular necrosis rates with these allografts. We report a successful case of a dual transplant with ECD allografts using a perfusion system. The biopsy appearance and the pump characteristics were suboptimal for these kidneys, making them unsuitable for single transplantation; however, the pair of transplanted kidneys provided increased nephron mass and functioned well. We recommend that ECD kidneys that are individually nontransplantable be evaluated for potential dual renal transplantation. Biopsy criteria and perfusion data guidelines must be developed to improve the success rates with ECD dual renal allografts. Finally, recipient selection is of utmost importance.

A review of utility-based allocation strategies to maximize graft years of deceased donor kidneys

With the continuing shortage of deceased donor kidneys coupled with a growing number of older potential recipients, there has been a greater acceptance of using older donor kidneys, including increased utility of expanded criteria donor (ECD) kidneys. In this review, we will look at the impact of using ECD kidneys on graft and patient survival, and to identify modifiable factors that may improve transplant outcomes in recipients receiving ECD kidneys. In addition, we will discuss whether the implementation of utility-based allocation strategies to maximize graft outcomes is an appropriate way forward to provide a better balance between utility and equity in the distribution of deceased donor kidneys.

Illinois statewide dual kidney transplantation experience--are we appropriately selecting kidneys?

PURPOSE

Dual kidney transplantation is a technique that some transplant centers have adopted to increase organ use. We investigated whether kidneys that were recovered and discarded were similar to those kidneys used for dual kidney transplantation.

MATERIALS AND METHODS

We reviewed all kidneys recovered, biopsied and placed on machine perfusion in the state of Illinois from January 2002 to October 2009. We selected those kidneys used in dual kidney transplant, and compared their characteristics to those of kidneys that were recovered and biopsied but ultimately discarded. The immediate and 1-year outcomes of the dual kidney transplant recipients were analyzed.

RESULTS

During the study period 60 dual transplants were performed while 94 kidney pairs were discarded. Overall donors from the used group had a lower mean creatinine clearance, older mean patient age, lower percentage of glomerulosclerosis, higher final flow rate and lower resistance. However, the comparison between those kidneys used successfully with 1-year graft survival and those discarded demonstrated only 3 less favorable parameters among the discarded group, namely a higher percentage of glomerulosclerosis (18.5% vs 13.9%, p=0.024), a higher degree of interstitial fibrosis and a higher final resistance (0.39 vs 0.31, p<0.001).

CONCLUSIONS

The considerable overlap in demographics, histology and perfusion parameters between used and discarded kidneys suggests that many kidneys that were recovered and discarded could have been used in dual kidney transplantation with acceptable outcomes. This highlights the need for further study of how kidneys are selected and used.

Dual kidney transplantation from expanded criteria deceased donors: Initial experience from single center

Aim:

To evaluate results of dual kidney transplantation from expanded criteria deceased donors.

Materials and Methods:

Between January 2000 and December 2009, 23 dual kidney transplantations were performed from expanded criteria deceased donors; 11 were from non-heart-beating donors and 12 from brain-dead heart-beating donors. All transplantations were performed in monolateral iliac fossa.

Results:

Two perioperative deaths occurred due to sepsis and multiorgan failure in non-heart-beating group, and one in brain dead group. One- and five-year graft and patient survival in recipients having organs from brain-death heart-beating group were 91.67%. In non-heart-beating group, 1- and 5-year graft survival was 65.45% and 81.82%, and 1- and 5-year patient survival was 43.64% and 61.36%, respectively.

Conclusion:

Dual kidney transplantation from expanded criteria brain dead donors has better graft and patient survival than from non-heart-beating donors.

Dual-kidney transplants as an alternative for very marginal donors: long-term follow-up in 63 patients

BACKGROUND

Organ shortage has led to the use of dual-kidney transplant (DKT) of very marginal donors into a single recipient to increase the use of marginal organs. To date, few data are available about the long-term outcome of DKT and its usefulness to increase the pool of available organ.

METHODS

We conducted a single-center cohort study of DKTs with longitudinal follow-up over an 8-year period. Between 1999 and 2007, 63 DKTs were performed. All kidneys from donors younger than 75 years refused by all centers for single transplantation, and kidneys from donors aged 75 years or older were routinely evaluated based on preimplantation glomerulosclerosis. Renal function, patient or graft survival, and perioperative complications were compared with 66 single kidneys from expanded criteria donors (ECD) and 63 ideal kidney donors.

RESULTS

After a median follow-up of 56 months, patient or graft survival was similar between the three groups. Twelve-, 36-, and 84-month creatinine clearance were similar for DKT and ECD (12 months: 58 and 59 mL/min; 36 months: 54 and 60 mL/min; and 84 months: 62 and 51 mL/min, respectively). For the study period, the routine evaluation of very marginal kidneys for DKT in our center has led to an increase of 47% in the transplants from donors aged 50 years or older, which represent 12% at the level of our organ procurement organization.

CONCLUSIONS

DKT patients can expect long-term results comparable with single kidney ECD. The implementation of a DKT program in our unit safely increased the pool of organs from marginal donors.

Technical aspects of unilateral dual kidney transplantation from expanded criteria donors: experience of 100 patients

One option for using organs from donors with a suboptimal nephron mass, e.g. expanded criteria donors (ECD) kidneys, is dual kidney transplantation (DKT). In adult recipients, DKT can be carried out by several techniques, but the unilateral placement of both kidneys (UDKT) offers the advantages of single surgical access and shorter operating time. One hundred UDKT were performed using kidneys from ECD donors with a mean age of 72 years (Group 1). The technique consists of transplanting both kidneys extraperitoneally in the same iliac fossa. The results were compared with a cohort of single kidney transplants (SKT) performed with the same selection criteria in the same study period (Group 2, n = 73). Ninety-five percent of UDKTs were positioned in the right iliac fossa, lengthening the right renal vein with an inferior vena cava patch. In 69% of cases, all anastomoses were to the external iliac vessels end-to-side. Surgical complications were comparable in both groups. At 3-year follow-up, patient and graft survival rates were 95.6 and 90.9% in Group 1, respectively. UDKT can be carried out with comparable surgical complication rates as SKT, leaving the contralateral iliac fossa untouched and giving elderly recipients a better chance of receiving a transplant, with optimal results up to 3-years follow-up.

Single versus dual renal transplantation from donors with significant arteriosclerosis on pre-implant biopsy

BACKGROUND

Transplantation of kidneys from donor with arteriosclerosis seen on pre-implantation biopsy has not been well studied.

METHODS

We retrospectively evaluated 20 dual kidney transplant (DKT) and 28 single (SKT) kidney transplant recipients with >or=12 months follow-up from donors with moderate arteriosclerosis (>or=25% luminal diameter narrowing).

RESULTS

Death censored graft survival was 100% and 79%, respectively (p = 0.0339). DKT recipients had significantly lower mean creatinine levels at one, three, six, and nine months and spent somewhat less time on the waiting list (181 +/- 160 vs. 318 +/- 306 d, p = 0.1429). DKT patients received kidneys from significantly older donors (64 +/- 7 vs. 54 +/- 11 yr; p = 0.0012), proportionately more expanded criteria donors (95% vs. 54%; p = 0.0029), and more donors with hypertension (81% vs. 48%, p = 0.0344) and death related to cerebrovascular accident (100% vs. 71%, p = 0.0143); however, more DKT kidneys underwent machine perfusion (95% vs. 57%, p = 0.0068). Baseline recipient variables were comparable between the two groups including age, race, gender, retransplantation, and HLA mismatch. Pre-implant biopsy was notable for similar frequencies of moderate interstitial fibrosis (10% vs. 14%, respectively) and glomerulosclerosis.

CONCLUSION

Among recipients of deceased-donor kidneys with >25% arteriosclerosis, short-term outcomes after DKT were superior to that of SKT grafts. This approach may help to expand the donor-organ pool while optimizing outcomes.

Donor-estimated GFR as an appropriate criterion for allocation of ECD kidneys into single or dual kidney transplantation

It has been suggested that dual kidney transplantation (DKT) improves outcomes for expanded criteria donor (ECD) kidneys. However, no criteria for allocation to single or dual transplantation have been assessed prospectively. The strategy of DKT remains underused and potentially eligible kidneys are frequently discarded. We prospectively compared 81 DKT and 70 single kidney transplant (SKT) receiving grafts from ECD donors aged >65 years, allocated according to donor estimated glomerular filtration rate (eGFR): DKT if eGFR between 30 and 60 mL/min, SKT if eGFR greater than 60 mL/min. Patient and graft survival were similar in the two groups. In the DKT group, 13/81 patients lost one of their two kidneys due to hemorrhage, arterial or venous thrombosis. Mean eGFR at month 12 was similar in the DKT and SKT groups (47.8 mL/min and 46.4 mL/min, respectively). Simulated allocation of kidneys according to criteria based on day 0 donor parameters such as those described by Remuzzi et al., Andres et al. and UNOS, did not indicate an improvement in 12-month eGFR compared to our allocation based on donor eGFR.

Renal transplantation in the elderly

Elderly patients are increasingly being considered for kidney transplantation due to a global explosion of the aging population with end-stage renal disease (ESRD). However, mounting scarcity of available organs for transplant has led to a wider disparity between organ supply and demand. Consequently, the criteria for accepting kidneys for transplantation have been extended in an attempt to allow the use of organs from elderly donors or those with significant co-morbidities, so-called "expanded criteria donor" (ECD) kidneys. Excellent outcomes have been achieved from ECD kidneys with appropriate donor and recipient profiling and selection. With increasing recovery efforts directed at older donors, the concept of age-matching is becoming more accepted as a method of optimizing utilization of organs in elderly donors and recipients. Utilization of pulsatile perfusion has further improved ECD outcomes and helped the decision-making process for the UNOS (United Network for Organ Sharing) offer. However, age-related immune dysfunction and associated co-morbidities make the elderly transplant recipients ever more susceptible to complications associated with immunosuppressive agents. Consequently, the elderly population is at a higher risk to develop infections and malignancy in the post-transplant period notwithstanding improved transplant outcomes. Appropriate immunosuppressive agents and dosages should be selected to minimize adverse events while reducing the risk of acute rejections and maximizing patient and renal allograft survival.

Glomerular function, structure, and number in renal allografts from older deceased donors

The 5-yr survival rate of renal allografts is significantly lower for grafts from older deceased donors than from younger deceased donors. For evaluation of the potential contribution of renal senescence in this shortened graft survival, glomerular function and structure were analyzed in allografts from deceased donors older than 55 yr ("aging") or younger than 40 yr ("youthful"). Aging donors had a significantly higher prevalence of sclerotic glomeruli (P < 0.002), and their nonsclerotic glomeruli tended to be larger, had a larger filtration surface area (P = 0.02), and had a higher single-nephron ultrafiltration coefficient (K(f); P = 0.07), suggesting a compensatory response to functional loss of glomeruli. After serum creatinine reached a stable nadir in the transplant recipients, GFR and its hemodynamic determinants were evaluated and the whole allograft K(f) was computed. Compared with the allografts from youthful donors, allografts from aging donors exhibited a 32% lower GFR, which was exclusively attributable to a 45% reduction in allograft K(f) (both P < 0.001). In addition, the number of functioning glomeruli per allograft was profoundly lower in grafts from aging donors than from youthful donors (3.6 +/- 2.1 x 10(5) versus 8.5 +/- 3.4 x 10(5); P < 0.01), and this could not be explained by the relatively modest 17% prevalence of global glomerulosclerosis in the aging group. The marked reduction in overall glomerular number in many aging donors may lead to a "remnant kidney" phenomenon, potentially explaining the shorter mean survival of these allografts.

Renal transplantation from extended criteria cadaveric donors: problems and perspectives overview

The critical shortage of organs available for renal transplantation has led to the consideration of alternative strategies for increasing the donor pool. Recently, the cadaveric kidney donor pool extended to donors who might have been deemed unsuitable in early times, leading to the concept of marginal donors and more recently to the notion of expanded criteria donors. Such organs are eligible for organ donation but, because of extreme age and other clinical characteristics, are expected to produce allograft at risk for diminished post-transplant function. Thus, the challenge is now to reduce the difference between graft outcome from patients grafted with marginal and 'optimal' donors. This implies appropriate transplantation strategies during pre-, peri- and post-transplantation phases including reduction of cold ischemia time, recipient selection, adaptation of immunosuppressive drug regimens, increase in nephron mass by dual kidney transplantation, and improvement in the graft selection process using histological criteria. This review summarizes current definition of a marginal donor and provides some guidance for clinical management of such transplant.

Dual Kidney Transplantation: A Case-Control Comparison With Single Kidney Transplantation From Standard and Expanded Criteria Donors

BACKGROUND

The purpose of this study was to perform a case-matched cohort analysis of dual kidney transplantation (DKT) from expanded criteria donors (ECDs) compared to single kidney transplantation (SKT) from concurrent ECDs and standard criteria donors (SCDs, defined as non-ECD).

METHODS

Deceased donor (DD) kidney transplants (KTs) performed at a single center between October 2001 and February 2006 were reviewed retrospectively. If the calculated DD creatinine clearance (CrCl) was <65 mL/min, then the kidneys were transplanted dually into a single patient. In the case of DKT and SKT from ECDs, low risk patients were chosen and informed consent was obtained. Patients in each group were matched for age, gender, race, transplant number, and time of transplant.

RESULTS

Of 294 adult DD KTs performed, 16 (5%) were DKTs, which were matched with 16 concurrent SCD and 16 ECD SKT patients. Mean donor age in years (65 DKT vs. 33 SCD vs. 61 ECD; P<0.0001) and mean donor CrCl in ml/min (54 DKT vs. 91 SCD vs. 76 ECD; P=0.002) were different between groups. Patient survival was 100% in the DKT and SCD SKT groups and 94% in the ECD SKT group (mean follow up 23-28 months); graft survival rates in the DKT, SCD, and ECD groups were 81%, 81%, and 94%, respectively (P=NS). Graft function, rejection, and morbidity were similar between groups.

CONCLUSIONS

DKT using kidneys from marginal ECDs is a viable option to counteract the growing shortage of available organs. Excellent short-term results and renal function can be achieved with older, low nephron mass donors provided that both kidneys are transplanted into a single recipient.

Dual Kidney Transplantation Using Midline Extraperitoneal Approach: Description of a Technique

Dual kidney transplantation is performed using organs from marginal donors that are considered unsuitable for single kidney transplantation. In this report, we describe a simple technique of transplanting these organs extraperitoneally through a lower midline incision.

[Double kidney transplantation--a method to increase the donor pool]

The patients number on the transplant waiting lists are continuously increasing. The number of donors and transplantations can not reach this acceleration. To increase the number of organs we can use living donor organs or carefully selected extended criteria organs. To achieve appropriate function with marginal donor kidneys we need to transplant both kidneys into the same recipient. At the Transplant Division of University of Texas during a two years period we performed 5 double kidney transplantations with organs refused by the local transplant services. We placed both kidneys to the same side, retroperitoneally. The recipients mean age was 44.4 years and two of them belonged to the immunological risk ethnic group. After the transplantation all kidneys showed immediate function. During the patients mean hospital stay (6.25 days) the serum creatinine level decreased from 1000 micromol/l to 350 micromol/l. The Glomerular Filtration Rate (GFR) increased from 7 ml/min to 41 ml/min. Two patients suffered acute rejection which influenced their kidney function. During our two year follow up all patients avoided haemodyalsis. Double kidney transplantation is an acceptable solution for expanding the donor pool. After consistent and cautious selection previously rejected kidneys can be used.

Immunosuppression for dual kidney transplantation with marginal organs: the old is better yet

Immunosuppressive protocols in dual kidney transplantation (DKT) are based on calcineurin inhibitors (CNI). We wonder whether a CNI-free immunosuppression can improve outcome in older patients receiving a DKT with marginal donor organs. Thirty-six were treated with CsA, MMF and prednisone (CsA group) and 42 with rATG, SRL, MMF and prednisone (SRL group). Incidence of delayed graft function and acute rejection was 44% and 11% in the CsA group, and 40% and 8% in the SRL group. CMV infection incidence was low in both protocols. Three-year patient survival was 89% in the CsA and 76% in the SRL group. One- and 3-year graft survival after censoring for dead with a functioning allograft was 94.2% and 94% in CsA and 95% and 90% in SRL, respectively. Renal function was similar in both groups whereas proteinuria was higher in the SRL group. Uninephrectomy due to graft thrombosis or urinary-related complications was numerically higher in the SRL (21%) than in the CsA group (8%) (p = 0.13) and it was associated with renal failure and proteinuria. In DKT, a new induction immunosuppressive protocol based on rATG, SRL, MMF and prednisone does not offer any advantage in comparison to the old CsA, MMF and prednisone.

Results of En Bloc Renal Transplants of Pediatric Deceased Donors into Adult Recipients

Various strategies have evolved to expand the donor pool due to the extreme shortage of organs. Herein we reviewed our experience with en bloc pediatric kidney transplantation since 1998.

METHODS

From January 1998 to December 2004, nine adult patients underwent kidney transplantation using en bloc kidneys from donors <5 years old (range, 1 to 4). The mean age of the recipients was 45.1 years (range, 34 to 57).

RESULTS

In recipients of en bloc pediatric transplantation, cold ischemia time ranged from 14 to 26.2 hours (mean, 21.3 hours). Mean serum creatinine at 3, 6, and 12 months after transplantation was 1.53 +/- 0.57, 1.27 +/- 0.27, and 1.15 +/- 0.26 mg/dL compared with 1.93 +/- 1.35, 1.81 +/- 1.17, and 1.73 +/- 0.85 (P = .08) in recipients of single kidneys from ideal cadaveric donors (UNOS criteria, n = 368). Patient and graft survival at 1 year were 88.8% compared with 91.2% and 85% with ideal donors (P = NS), respectively. Three cases required additional surgery. There was one death due to a cerebral vascular accident.

CONCLUSION

The present study confirmed the excellent results achieved with transplantation using en bloc kidneys from young donors.

Ways to boost kidney transplant viability: a real need for the best use of older donors

Using kidneys from expanded criteria donors (ECD) increased transplant activity but resulted in a reduced graft survival. The relatively poor long-term outcome of ECD grafts may be the consequence of an imbalance between the number of viable nephrons supplied and the metabolic demand of the recipient. Providing more nephrons by dual transplants may improve outcomes but fails, per se, to confer the same benefit of single transplants from young donors. A biopsy-based score system has been presented by a panel of pathologists to assess whether kidneys from donors older than 60 years still contain enough viable nephrons to be made available for transplantation, and whether single or dual transplantation should be used. Allocating kidneys from older donors to a single or dual transplant on the basis of this scoring system allowed achieving a graft survival similar to that of single transplants from ideal donors and remarkably superior to that of single transplants from older donors not evaluated histologically before implantation. Thus, preimplantation histologic evaluation maximizes the success of ECD transplants and protects recipients from receiving organs at increased risk of premature failure. This may limit the number of patients who eventually must resume dialysis and need second transplants.

Renal transplantation: older recipients and donors

The majority of patients receiving a renal allograft, including a kidney from an older donor, do well. Renal transplantation from a living donor is associated with distinct advantages, including prolonged allograft survival. When live donors are not available, however, deceased donor kidneys provide suitable renal function that frequently lasts the lifetime of elderly recipients. Elderly patients who receive a kidney transplant enjoy improved survival, better quality of life, and lower medical costs than those who remain on dialysis.

Experience with dual kidney transplants from donors at the extremes of age

BACKGROUND

Dual kidney transplantation (DKT) from donors at the extremes of age represents one approach to expanding the organ donor pool. The purpose of this study was to review our experience with DKT from older donors and en bloc KT (EBKT) from small pediatric donors.

METHODS

Deceased donor KTs performed at our center between October 2001 and November 2005, were reviewed retrospectively. If the calculated creatinine clearance in an expanded criteria donor was <65 mL/min, then the kidneys were transplanted dually into a single adult recipient. If a pediatric donor weighed <15 kg, then the kidneys were transplanted en bloc. In both instances, low-risk recipients were chosen (primary transplant, low sensitization, body mass index <25 kg/m(2), human leukocyte antigen matching). Donor, recipient, and transplant characteristics, waiting time, and outcomes were examined.

RESULTS

Of a total of 279 deceased donor KTs during the 49-month study period, 15 (5%) recipients underwent DKT and 5 (2%) underwent EBKT. Mean donor age was 65.4 years and 21.4 months in the DKT and EBKT groups, respectively. Patient survival rates in both groups were 100% with a mean follow-up of 22 months (minimum, 6 months). Kidney graft survival rates were 80% (12/15) and 60% (3/5) in the DKT and EBKT groups, respectively. The combined incidence of delayed graft function was 10%. Mean 12-month glomerular filtration rates were 46 mL/min and 66 mL/min in the DKT and EBKT groups, respectively.

CONCLUSIONS

DKT using kidneys from marginal elderly donors and EBKT from small pediatric donors appear to offer a viable option to counteract the shortage of acceptable kidney donors.

Intermediate-term outcomes with expanded criteria deceased donors in kidney transplantation: a spectrum or specter of quality?

OBJECTIVE

To compare intermediate-term outcomes in adult recipients of expanded criteria (ECD) versus concurrent standard criteria (SCD) deceased donor kidney transplants at a single center using a standardized approach.

SUMMARY BACKGROUND DATA

Expanded criteria donors (ECDs) are a source of kidneys that increase the donor organ pool, but the value of transplanting these kidneys has been questioned because of concerns regarding diminished survival and predicted poorer intermediate-term outcomes.

METHODS

Over a 47-month period, we performed 244 deceased donor kidney transplants into adult recipients, including 143 from SCDs and 101 from ECDs. Management algorithms were implemented to preserve nephron function, and recipient selection for an ECD kidney transplant was based on low immunologic risk. All patients received depleting antibody induction in combination with tacrolimus and mycophenolate mofetil. A total of 188 patients (77%) had at least a 1-year follow-up.

RESULTS

ECDs were older, had a higher BMI, had an increased incidence of cerebrovascular brain death and preexisting donor hypertension, and had a lower estimated creatinine clearance (CrCl, all P < 0.01) compared with SCDs. Cold ischemic times were similar between groups, but more ECD kidneys were preserved with pulsatile perfusion (P < 0.01). ECD kidney recipients were older, less sensitized, had a lower BMI, had fewer 0-antigen mismatches, and had a shorter waiting time (all P < 0.01) compared with SCD kidney recipients. Actual patient (93%) and kidney graft (83%) survival rates were similar between groups with a mean follow-up of 24 months. The rates of delayed graft function (DGF), acute rejection, readmissions, operative complications, major infections, and resource utilization were comparable between groups. Renal function followed longitudinally was consistently better in SCD patients (P < 0.05). Black recipients had higher rates of DGF, acute rejection, and graft loss (P < 0.05), but the effects were less pronounced in the ECD group.

CONCLUSIONS

By appropriate donor and recipient profiling and the use of management algorithms to project and protect renal function, excellent intermediate-term outcomes can be achieved with ECD kidney transplants that are comparable to SCD kidney transplants.