Cold ischemia time and allograft outcomes in live donor renal transplantation: is live donor organ transport feasible?

Delayed graft function post renal transplantation: a review on animal models and therapeutics

The incidence of end-stage renal disease (ESRD) has been increasing worldwide. Its treatment involves renal replacement therapy, either by dialyses or renal transplantation from a living or deceased donor. Although the initial mortality rates for patients on dialysis are comparable with kidney transplant recipients, the quality of life and long-term prognosis are greatly improved in transplanted patients. However, there is a large gap between availability and need for donor kidneys. This has led to the increase in the use of expanded kidney donor criteria. Allograft dysfunction immediately after transplant sets it up for many complications, such as acute rejection and shorter allograft survival. Delayed graft function (DGF) is one of the immediate posttransplant insults to the kidney allograft, which is increasing in prevalence due to efforts to maximize the available donor pool for kidneys and use of expanded kidney donor criteria. In this review, we discuss the risk factors for DGF, its implications for long-term allograft survival, animal models of DGF, and the therapeutic options currently under evaluation for prevention and management of DGF.

The Impact of Cold Ischaemia Time on Outcomes of Living Donor Kidney Transplantation: A Systematic Review and Meta-Analysis

Studies have been carried out to investigate the effect of a prolonged cold ischaemia time (CIT) on the outcomes of living donor kidney transplantation (LDKT). There is no clear consensus in the literature about the effects of CIT on LDKT outcomes, and therefore, we performed a systematic review and meta-analysis to provide evidence on this subject. Searches were performed in five databases up to 12 July 2021. Articles comparing different CIT in LDKT describing delayed graft function (DGF), graft and patient survival, and acute rejection were considered for inclusion. This study is registered with PROSPERO, CRD42019131438. In total, 1452 articles were found, of which eight were finally eligible, including a total of 164,179 patients. Meta-analyses showed significantly lower incidence of DGF (odds ratio (OR) = 0.61, p < 0.01), and significantly higher 1-year graft survival (OR = 0.72, p < 0.001) and 5-year graft survival (OR = 0.88, p = 0.04), for CIT of less than 4 h. Our results underline the need to keep CIT as short as possible in LDKT (ideally < 4 h), as a shorter CIT in LDKT is associated with a statistically significant lower incidence of DGF and higher graft survival compared to a prolonged CIT. However, clinical impact seems limited, and therefore, in LDKT programmes in which the CIT might be prolonged, such as kidney exchange programmes, the benefits outweigh the risks. To minimize these risks, it is worth considering including CIT in kidney allocation algorithms and in general take precautions to protect high risk donor/recipient combinations.

Advances in Kidney Preservation Techniques and Their Application in Clinical Practice

The use of cold preservation solutions to rapidly flush and cool the kidney followed by static cold storage in ice has been the standard kidney preservation technique for the last 50 y. Nonetheless, changing donor demographics that include organs from extended criteria donors and donation after circulatory death donors have led to the adoption of more diverse techniques of preservation. Comparison of hypothermic machine perfusion and static cold storage techniques for deceased donor kidneys has long been debated and is still contested by some. The recent modification of hypothermic machine perfusion techniques with the addition of oxygen or perfusion at subnormothermic or near-normothermic temperatures are promising strategies that are emerging in clinical practice. In addition, the use of normothermic regional perfusion to resuscitate abdominal organs of donation after circulatory death donors in situ before cold flushing is also increasingly being utilized. This review provides a synopsis of the different types of preservation techniques including their mechanistic effects and the outcome of their application in clinical practice for different types of donor kidney.

The Impact of Cold Ischaemia Time On Outcomes of Living Donor Kidney Transplantation in the UK Living Kidney Sharing Scheme

OBJECTIVE

To assess the impact of cold ischaemia time (CIT) on living donor kidney transplantation (LDKT) outcomes in the UK living kidney sharing scheme (UKLKSS) versus outside the scheme.

BACKGROUND

LDKT provides the best treatment option for end-stage kidney disease (ESKD) patients. ESKD patients with an incompatible living donor still have an opportunity to be transplanted through Kidney Exchange Programmes (KEP). In KEPs where kidneys travel rather than donors, CIT can be prolonged.

METHODS

Data from all UK adult LDKT between 2007 and 2018 were analysed.

RESULTS

9969 LDKT were performed during this period, of which 1396 (14%) were transplanted through the UKLKSS, which we refer to as KEP. Median CIT was significantly different for KEP versus non-KEP (339 versus 182 minutes, p < 0.001). KEP LDKT had a higher incidence of delayed graft function (DGF) (4.08% versus 6.97%, p < 0.0001), lower 1-year (eGFR 57.90 versus 55.25 ml/min, p = 0.04) and 5-year graft function (eGFR 55.62 versus 53.09 ml/min, p = 0.01) compared to the non-KEP group, but 1- and 5-year graft survival were similar. Within KEP, a prolonged CIT was associated with more DGF (9.26% versus 4.80%, p = 0.03), and lower graft function at 1-year and 5-years (eGFR = 55 vs 50 ml/min, p = 0.02), but had no impact on graft survival.

CONCLUSION

Whilst CIT was longer in KEP, associated with more DGF and lower graft function, excellent 5-year graft survival similar to non-KEP was found.

Long Hemodialysis Duration Predicts Delayed Graft Function in Renal Transplant Recipients From Living Donor: A Single-Center Study

BACKGROUND

This study aims to determine the ratio of delayed graft function in renal transplant recipients from living donors and the predictive value of hemodialysis time before transplant for delayed graft function.

METHODS

We conducted a study on 116 adult patients who were diagnosed with end-stage kidney disease and were treated with hemodialysis and transplanted kidneys from living donors for 2 years (from June 2018 to June 2020). Delayed graft function event was collected for each patient.

RESULTS

The recipients had a median age of 36.5 years old, in which 55.2% of them were men, 4.3% of them had the diabetic mellitus, and the median hemodialysis duration was 6 months. The ratio of positive panel-reactive antibody was 33.6% and vascular reconstruction of the donor's kidney was 16.4%. The ratio of delayed graft function was 12.2% (14 of 116 patients). Delayed graft function significantly related to positive panel-reactive antibody, long duration of hemodialysis before transplant, and vascular reconstruction of donor's kidney with P < .001. Duration of hemodialysis before kidney transplant had a predictive value for delayed graft function (area under the curve, 0.83; P < .001).

CONCLUSION

Delayed graft function was not rare in renal transplant recipients from living donors. Duration of hemodialysis before kidney transplant was a good predictor for delayed graft function.

Winter is coming: the future of cryopreservation

The preservative effects of low temperature on biological materials have been long recognised, and cryopreservation is now widely used in biomedicine, including in organ transplantation, regenerative medicine and drug discovery. The lack of organs for transplantation constitutes a major medical challenge, stemming largely from the inability to preserve donated organs until a suitable recipient is found. Here, we review the latest cryopreservation methods and applications. We describe the main challenges-scaling up to large volumes and complex tissues, preventing ice formation and mitigating cryoprotectant toxicity-discuss advantages and disadvantages of current methods and outline prospects for the future of the field.

Risk factors for delayed graft function and their impact on graft outcomes in live donor kidney transplantation

BACKGROUND

Delayed graft function (DGF) is a manifestation of acute kidney injury uniquely framed within the transplant process and a predictor of poor long-term graft function1. It is less common in the setting of living donor (LD) kidney transplantation. However, the detrimental impact of DGF on graft survival is more pronounced in LD2.

PURPOSE

To study the effects of DGF in the setting of LD kidney transplantation.

METHODS

We performed a retrospective analysis of LD kidney transplantations performed between 2010 and 2018 in the UNOS/OPTN database for DGF and its effect on graft survival.

RESULTS

A total of 42,736 LD recipients were identified, of whom 1115 (2.6%) developed DGF. Recipient dialysis status, male gender, diabetes, end-stage renal disease, donor age, right donor nephrectomy, panel reactive antibodies, HLA mismatch, and cold ischemia time were independent predictors of DGF. Three-year graft survival in patients with and without DGF was 89% and 95%, respectively. DGF was the greatest predictor of graft failure at three years (hazard ratio = 1.766, 95% CI: 1.514-2.059, P = 0.001) and was associated with higher rates of rejection (9% vs. 6.28%, P = 0.0003). Among patients with DGF, the graft survival rates with and without rejection were not different.

CONCLUSION

DGF is a major determinant of poor graft functional outcomes, independent of rejection.

The "oldest and coldest" shipped living donor kidneys transplanted through kidney paired donation

To date, thousands of living donor kidneys have been shipped through kidney paired donation (KPD). To expand on this growing segment of living donor transplantation, we evaluated the effect of advanced age donation ("oldest kidneys") and prolonged cold ischemia time ("coldest kidneys") on graft function and survival using the National Kidney Registry database from February 2008 to May 2018. Donors were stratified by age at time of donation (<65 or ≥65 years) and kidneys were stratified by cold ischemia time (<16 or ≥16 hours). We evaluated delayed graft function and death-censored graft failure (DCGF) for up to seven posttransplant years. Of the 2363 shipped living donor kidney transplants, 4.1% of donors were ≥65 years and 6.0% of transplanted kidneys had cold ischemia times ≥16 hours. Delayed graft function and DCGF occurred in 5.2% and 4.7% of cases. There were no significant associations between delayed graft function and donor age (P = .947) or cold ischemia (P = .532). Donor age and cold ischemia time were not predictive of delayed graft function (OR = 0.86,1.20; P = .8, .6) or DCGF (HR = 1.38,0.35, P = .5, .1). These findings may alleviate concerns surrounding the utilization of kidneys from older donors or those originating from distant transplant centers.

Anti-donor MHC Class II Alloantibody Induces Glomerular Injury in Mouse Renal Allografts Subjected to Prolonged Cold Ischemia

BACKGROUND

The mechanisms underlying the effects of prolonged cold-ischemia storage on kidney allografts are poorly understood.

METHODS

To investigate effects of cold ischemia on donor-reactive immune responses and graft pathology, we used a mouse kidney transplantation model that subjected MHC-mismatched BALB/c kidney allografts to cold-ischemia storage for 0.5 or 6 hours before transplant into C57BL/6 mice.

RESULTS

At day 14 post-transplant, recipients of allografts subjected to 6 versus 0.5 hours of cold-ischemia storage had increased levels of anti-MHC class II (but not class I) donor-specific antibodies, increased donor-reactive T cells, and a significantly higher proportion of transplant glomeruli infiltrated with macrophages. By day 60 post-transplant, allografts with a 6 hour cold-ischemia time developed extensive glomerular injury compared with moderate pathology in allografts with 0.5 hour of cold-ischemia time. Pathology was associated with increased serum levels of anti-class 2 but not anti-class 1 donor-specific antibodies. Recipient B cell depletion abrogated early macrophage recruitment, suggesting augmented donor-specific antibodies, rather than T cells, increase glomerular pathology after prolonged cold ischemia. Lymphocyte sequestration with sphingosine-1-phosphate receptor 1 antagonist FTY720 specifically inhibited anti-MHC class II antibody production and abrogated macrophage infiltration into glomeruli. Adoptive transfer of sera containing anti-donor MHC class II antibodies or mAbs against donor MHC class II restored early glomerular macrophage infiltration in FTY720-treated recipients.

CONCLUSIONS

Post-transplant inflammation augments generation of donor-specific antibodies against MHC class II antigens. Resulting MHC class II-reactive donor-specific antibodies are essential mediators of kidney allograft glomerular injury caused by prolonged cold ischemia.

Intraoperative Fluid Restriction is Associated with Functional Delayed Graft Function in Living Donor Kidney Transplantation: A Retrospective Cohort Analysis

Background: In 2016 we observed a marked increase in functional delayed graft function (fDGF) in our living donor kidney transplantation (LDKT) recipients from 8.5% in 2014 and 8.8% in 2015 to 23.0% in 2016. This increase coincided with the introduction of a goal-directed fluid therapy (GDFT) protocol in our kidney transplant recipients. Hereupon, we changed our intraoperative fluid regimen to a fixed amount of 50 mL/kg body weight (BW) and questioned whether the intraoperative fluid regimen was related to this increase in fDGF. Methods: a retrospective cohort analysis of all donors and recipients in our LDKT program between January 2014–February 2017 (n = 275 pairs). Results: Univariate analysis detected various risk factors for fDGF. Dialysis dependent recipients were more likely to develop fDGF compared to pre-emptively transplanted patients (p < 0.001). Recipients developing fDGF received less intraoperative fluid (36 (25.9–50.0) mL/kg BW vs. 47 (37.3–55.6) mL/kg BW (p = 0.007)). The GDFT protocol resulted in a reduction of intraoperative fluid administration on average by 850 mL in total volume and 21% in mL/kg BW compared to our old protocol (p < 0.001). In the unadjusted analysis, a higher intraoperative fluid volume in mL/kg BW was associated with a lower risk for the developing fDGF (OR 0.967, CI (0.941–0.993)). After adjustment for the confounders, prior dialysis and the use of intraoperative noradrenaline, the relationship of fDGF with fluid volume was still apparent (OR 0.970, CI (0.943–0.998)). Conclusion: Implementation of a GDFT protocol led to reduced intraoperative fluid administration in the LDKT recipients. This intraoperative fluid restriction was associated with the development of fDGF.

Association of Cold Ischemia Time With Acute Renal Transplant Rejection

BACKGROUND

Kidney transplantation holds much promise as a treatment of choice for patients with end-stage kidney disease. The impact of cold ischemia time (CIT) on acute renal transplant rejection (ARTR) remains to be fully studied in a large cohort of renal transplant patients.

METHODS

From the Organ Procurement and Transplantation Network database, we analyzed 63 798 deceased donor renal transplants performed between 2000 and 2010. We assessed the association between CIT and ARTR. We also evaluated the association between recipient age and ARTR.

RESULTS

Six thousand eight hundred two (11%) patients were clinically diagnosed with ARTR. Longer CIT was associated with an increased risk of ARTR. After multivariable adjustment, compared with recipients with CIT < 12 hours, the relative risk of ARTR was 1.13 (95% confidence interval, 1.04-1.23) in recipients with CIT ≥ 24 hours. The association of CIT and ARTR was more pronounced in patients undergoing retransplantation: compared with recipients with CIT less than 12 hours, the relative risk of ARTR was 1.66 (95% confidence interval, 1.01-2.73) in recipients with CIT of 24 hours or longer. Additionally, older age was associated with a decreased risk of ARTR. Compared with recipients aged 18 to 29 years, the relative risk of ARTR was 0.50 (95% confidence interval, 0.45-0.57) in recipients 60 years or older. Longer CIT was also associated with increased risk of death-censored graft loss. Compared with recipients with CIT less than 12 hours, the hazard ratio of death-censored graft loss was 1.22 (95% confidence interval, 1.14-1.30) in recipients with CIT of 24 hours or longer.

CONCLUSIONS

Prolonged CIT is associated with an increased risk of ARTR and death-censored graft loss. Older age was associated with a lower risk of ARTR.

The first 9 years of kidney paired donation through the National Kidney Registry: Characteristics of donors and recipients compared with National Live Donor Transplant Registries

The practice of kidney paired donation (KPD) is expanding annually, offering the opportunity for live donor kidney transplant to more patients. We sought to identify if voluntary KPD networks such as the National Kidney Registry (NKR) were selecting or attracting a narrower group of donors or recipients compared with national registries. For this purpose, we merged data from the NKR database with the Scientific Registry of Transplant Recipients (SRTR) database, from February 14, 2008, to February 14, 2017, encompassing the first 9 years of the NKR. Compared with all United Network for Organ Sharing (UNOS) live donor transplant patients (49 610), all UNOS living unrelated transplant patients (23 319), and all other KPD transplant patients (4236), the demographic and clinical characteristics of NKR transplant patients (2037) appear similar to contemporary national trends. In particular, among the NKR patients, there were a significantly (P < .001) greater number of retransplants (25.6% vs 11.5%), hyperimmunized recipients (22.7% vs 4.3% were cPRA >80%), female recipients (45.9% vs 37.6%), black recipients (18.2% vs 13%), and those on public insurance (49.7% vs 41.8%) compared with controls. These results support the need for greater sharing and larger pool sizes, perhaps enhanced by the entry of compatible pairs and even chains initiated by deceased donors, to unlock more opportunities for those harder-to-match pairs.

Association of Slow Graft Function with Long-Term Outcomes in Kidney Transplant Recipients

Background

Whether slow graft function (SGF) represents an intermediate phenotype between immediate graft function (IGF) and delayed graft function (DGF) in kidney transplant recipients is unknown.

Material/Methods

In a retrospective cohort analysis of 1,222 kidney transplant recipients, we classified patients as having IGF, SGF, and DGF using two different schemas. SGF was defined as serum creatinine (Cr) ≥3.0 mg/dL by postoperative day 5 in Schema 1, and in Schema 2, SGF was defined as Cr >1.5 mg/dL plus a creatinine reduction ratio <20% between postoperative days 1 and 3. A complementary log-log model was used to examine the association of graft function with graft survival and patient survival.

Results

Mean age of study patients was 51.5±13.3 years, 59.9% were male, and 66.7% were white. In Schema 1, SGF and DGF were associated with comparable increases in risk of graft failure compared to IGF (hazard ratio (HR) 1.46, 95% confidence intervals (CI) 1.02–2.10 for SGF and HR 1.56, CI 1.11–2.22 for IGF); estimates were similar for Schema 2 (HR 1.52, CI 1.05–2.20 for SGF and HR 1.54, CI 1.10–2.17 for IGF). However, for mortality, outcomes for SGF were similarly to IGF, both SGF and IGF were associated with lower risk relative to DGF (HR 0.54, CI 0.36–0.80 for SGF in Schema 1; HR 0.58, CI 0.39–0.85 for SGF in Schema 2).

Conclusions

These findings suggest that SGF may be a marker for graft failure but not for mortality, and SGF may therefore represent a phenotype separate from IGF and DGF.

Cold ischemia time up to 16 hours has little impact on living donor kidney transplant outcomes in the era of kidney paired donation

In living donor transplantation, cold ischemia time is a concern in transplants involving kidney paired donation. The impact of cold ischemia time over eight hours is unknown. Here we examined the association of cold ischemia time with delayed graft function and allograft loss among 48,498 living recipients in the Scientific Registry of Transplant Recipients registry. The incidence of delayed graft function was low but significantly higher among patients with longer cold ischemia times (0-2.0 hours: 3.3%; 2.1-4.0 hours: 3.9%; 4.1-8.0 hours: 4.3%; 8.1-16.0 hours: 5.5%). In multivariate analyses, only those with cold ischemia times of 8.1-16.0 hours had increased odds of delayed graft function (odds ratio 1.47; 95% confidence interval 1.05-2.05) compared to patients with times of 0-2.0 hours. In multivariate time-to-event analyses, cold ischemia times of 16 hours or less were not associated with allograft loss from any cause including death or death-censored graft loss with hazard ratios for cold ischemia times between 8.0-16.0 hours of 0.97 (95% confidence interval 0.74-1.26) and 1.09 (0.81-1.48) compared to patients with times of 0-2.0 hours). The results were consistent in paired and non-kidney paired donation transplants and in those with living donors over 50 years of age. In subgroup analysis restricted to kidney paired donation recipients, there was no difference in the risk of delayed graft function with an odds ratio of 1.40 (0.88, 2.40) or all-cause graft loss with a hazard ratio of 0.89 (0.62, 1.30) in transplant recipients who received kidneys that were shipped versus not shipped. Thus, a cold ischemia time up to 16 hours has limited impact on living donor outcomes. These findings may help expand living donor transplantation through kidney paired donation.

International kidney paired donation transplantations to increase kidney transplant of O group and highly sensitized patient: First report from India

AIM

To report the first international living related two way kidney paired donation (KPD) transplantation from India which occurred on 17^th February 2015 after legal permission from authorization committee.

METHODS

Donor recipient pairs were from Portugal and India who were highly sensitized and ABO incompatible with their spouse respectively. The two donor recipient pairs had negative lymphocyte cross-matching, flow cross-match and donor specific antibody in two way kidney exchange with the intended KPD donor. Local KPD options were fully explored for Indian patient prior to embarking on international KPD.

RESULTS

Both pairs underwent simultaneous uneventful kidney transplant surgeries and creatinine was 1 mg/dL on tacrolimus based immunosuppression at 11 mo follow up. The uniqueness of these transplantations was that they are first international KPD transplantations in our center.

CONCLUSION

International KPD will increases quality and quantity of living donor kidney transplantation. This could be an important step to solving the kidney shortage with additional benefit of reduced costs, improved quality and increased access for difficult to match incompatible pairs like O blood group patient with non-O donor and sensitized patient. To the best of our knowledge this is first international KPD transplantation from India.

Six end-stage renal disease patients benefited from first non-simultaneous single center 6-way kidney exchange transplantation in India

AIM

To avoid desensitization protocols and ABO incompatible kidney transplantation (KT) due to high costs and increased risk of infections from intense immunosuppression.

METHODS

We present institutional ethical review board - approved study of single center 6-way kidney exchange transplantation. The participants comprised ABO incompatibility (n = 1); positive cross-match and/or presence of donor specific antibody (n = 5). The average time required from registration in kidney paired donation (KPD) registry to find suitable donors was 45 d and time required to perform transplants after legal permission was 2 mo.

RESULTS

Graft and patient survival were 100%, and 100%, respectively. One patient had biopsy-proven acute borderline T cell rejection (Banff update 2013, type 3). Mean serum creatinine was 0.8 mg/dL at 9 mo follow-up. The waiting time in KPD was short as compared to deceased donor KT.

CONCLUSION

We report first non-simultaneous, single center, 6-way kidney exchange transplantation from India. Our experience will encourage other centers in India to undertake this practice.

Impact of grafting using thin upper pole artery ligation on living-donor adult kidney transplantation: The STROBE study

This study aimed to investigate the impact of grafting using thin upper pole artery ligation for living-donor adult kidney transplantation. Few reports have examined the safety of thin upper pole artery ligation.Between January 2008 and May 2015, 613 consecutive living-donor adult kidney transplantations were performed. We excluded 21 recipients who experienced graft loss due to factors that were unrelated to surgical complications and 3 recipients with grafts treated with arterial reconstruction and thin upper pole artery ligation for 3 arteries. We included 439 kidney grafts with single arteries (Single Artery Group), 123 with reconstructed arteries (Arterial Reconstruction Group) and 27 with ligated thin upper pole arteries (Arterial Ligation Group) in this retrospective cohort study. To evaluate the safety of thin upper pole artery ligation, we compared the Arterial Ligation Group with the Single Artery and Arterial Reconstruction groups. We evaluated the characteristics of the enrolled donors, recipients, and their grafts. Thereafter, we investigated recipients' perioperative and postoperative estimated glomerular filtration rate (eGFR) and complication rates.Significant differences among the 3 groups were identified for donor sex and endoscopic nephrectomy rates. Recipient eGFR and the complication rates were adjusted according to these factors. The perioperative and postoperative eGFR of recipients did not differ significantly in the Arterial Reconstruction and Single Artery groups with low complication rates.Thin upper pole artery ligation is a safe procedure for living-donor adult kidney transplantation and may prevent unnecessary arterial reconstruction and associated complications.

Prolonged Ischemic Time, Delayed Graft Function, and Graft and Patient Outcomes in Live Donor Kidney Transplant Recipients

The association between prolonged cold ischemic time (CIT) and graft and patient outcomes in live donor kidney transplant recipients remains unclear. The aims of this study were to examine the association of CIT with delayed graft function and graft loss in live donor kidney transplant recipients and those who participated in the Australian Paired Kidney Exchange program using data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry. Of 3717 live donor transplant recipients between 1997 and 2012 who were followed for a median of 6.6 years (25 977 person-years), 224 (25%) experienced CIT >4-8 h. Donor age was an effect modifier between CIT and graft outcomes. In recipients who received kidneys from older donors aged >50 years, every hour of increase in CIT was associated with adjusted odds of 1.28 (95% confidence interval [CI] 1.07-1.53, p = 0.007) for delayed graft function, whereas CIT >4-8 h was associated with adjusted hazards of 1.93 (95% CI 1.21-3.09, p = 0.006) and 1.91 (95% CI 1.05-3.49, p = 0.035) for overall and death-censored graft loss, respectively, compared with CIT of 1-2 h. Attempts to reduce CIT in live donor kidney transplants involving older donor kidneys may lead to improvement of graft outcomes.

Effect of cold ischaemia time on outcome after living donor renal transplantation

BACKGROUND

The aim of the present study was to determine the effects of cold ischaemia time (CIT) on living donor kidney transplant recipients in a large national data set.

METHODS

Data from the National Health Service Blood and Transplant and UK Renal Registry databases for all patients receiving a living donor kidney transplant in the UK between January 2001 and December 2014 were analysed. Patients were divided into three groups depending on CIT (less than 2 h, 2-4 h, 4-8 h). Risk-adjusted outcomes were assessed by multivariable analysis adjusting for discordance in both donor and recipient characteristics.

RESULTS

Outcomes of 9156 transplants were analysed (CIT less than 2 h in 2662, 2-4 h in 4652, and 4-8 h in 1842). After adjusting for confounders, there was no significant difference in patient survival between CIT groups. Recipients of kidneys with a CIT of 4-8 h had excellent graft outcomes, although these were slightly inferior to outcomes in those with a CIT of less than 2 h, with risk-adjusted rates of delayed graft function of 8·6 versus 4·3 per cent, and 1-year graft survival rates of 96·2 versus 97·1 per cent, respectively.

CONCLUSION

The detrimental effect of prolonging CIT for up to 8 h in living donation kidney transplantation is marginal.

Challenges of kidney paired donation transplants involving multiple donor and recipient surgeons across Australia

BACKGROUND

The Australian kidney paired donation program adopted the principles of within-chain simultaneous live donor surgery and of organ transport, with the requirement of keeping cold ischemia time (CIT) to <12 h. Whether these principles could be adhered to and what impact on transplant outcome they might have is unknown.

METHODS

We evaluated the logistic challenges and outcomes of the first 100 kidney transplants performed in the Australian kidney paired donation program.

RESULTS

Within 4 years, 17 donor surgeons at 12 centres were involved in 37 chain exchange surgeries. Sixteen kidneys were transplanted at the same hospital and 84 required transport to the recipient hospital. Mean (±SD) within chain anaesthetic induction time variability was 8 ± 18 min and mean individual surgeon operating time was 115 ± 44 min. In two cases, delays during donor surgery resulted in increased CIT by 1 h because of deferred transport. CIT was 2.6 ± 0.6 h for non-shipped and 6.8 ± 2.8 h for shipped kidneys, four kidneys had CIT of 12-14 h. Immediate allograft function was observed in 85% of recipients, with no difference between shipped and non-shipped kidneys. There were only two cases of delayed graft function requiring temporary dialysis; both had CIT <7 h. There was no difference in serum creatinine at 1 month between non-shipped and shipped kidneys (105 ± 26 versus 112 ± 50 µmol/L) and allograft survival at 1 year was 97%.

CONCLUSION

The study provided a favourable audit of kidney transplant activity, despite challenges of simultaneous surgery, organ transport coordination and prolonged CIT. The decision to ship donor kidneys rather than the donor was demonstrated to be feasible and safe.

Outcomes of kidney paired donation transplants in relation to shipping and cold ischaemia time

To assess the impact of shipping distance and cold ischaemia time (CIT) of shipped organs in a kidney paired donation (KPD) programme, we evaluated the outcomes of the initial 100 kidney transplants performed in the Australian KPD programme. In a 44-month period, 12 centres were involved in fifteen 2-way, twenty 3-way, one 4-way and one 6-way exchanges. Sixteen kidneys were transplanted at the same hospital (CIT 2.6 ± 0.6 h) and 84 required transport to the recipient hospital (CIT 6.8 ± 2.8 h). A spontaneous fall in serum creatinine by at least 10% within 24 h was observed in 85% of recipients, with no difference between nonshipped and shipped kidneys. There were two cases of transient delayed graft function requiring dialysis and patient and graft survival at 1 year were 99% and 97%, respectively. There was no difference in recipients of nonshipped compared with shipped kidneys with regard to serum creatinine at 1 month (mean difference (MD) 7.3 μmol/l, 95% CI -20.2 to 34.8, P = 0.59), 1-year graft survival (MD 3.9%, 95% CI -5.4 to 13.2, P = 0.41) or patient survival (MD -2.4%, 95% CI -10.0 to 5.2, P = 0.54). Despite prolonged CIT for interstate exchanges, the programme's decision to ship donor kidneys rather than the donor appears to be safe.

Validating Early Post-Transplant Outcomes Reported for Recipients of Deceased Donor Kidney Transplants

BACKGROUND AND OBJECTIVES

Data reported to the Organ Procurement and Transplantation Network (OPTN) are used in kidney transplant research, policy development, and assessment of center quality, but the accuracy of early post-transplant outcome measures is unknown.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Deceased Donor Study (DDS) is a prospective cohort study at five transplant centers. Research coordinators manually abstracted data from electronic records for 557 adults who underwent deceased donor kidney transplantation between April of 2010 and November of 2013. We compared the post-transplant outcomes of delayed graft function (DGF; defined as dialysis in the first post-transplant week), acute rejection, and post-transplant serum creatinine reported to the OPTN with data collected for the DDS.

RESULTS

Median kidney donor risk index was 1.22 (interquartile range [IQR], 0.97-1.53). Median recipient age was 55 (IQR, 46-63) years old, 63% were men, and 47% were black; 93% had received dialysis before transplant. Using DDS data as the gold standard, we found that pretransplant dialysis was not reported to the OPTN in only 11 (2%) instances. DGF in OPTN data had a sensitivity of 89% (95% confidence interval [95% CI], 84% to 93%) and specificity of 98% (95% CI, 96% to 99%). Surprisingly, the OPTN data accurately identified acute allograft rejection in only 20 of 47 instances (n=488; sensitivity of 43%; 95% CI, 17% to 73%). Across participating centers, sensitivity of acute rejection varied widely from 23% to 100%, whereas specificity was uniformly high (92%-100%). Six-month serum creatinine values in DDS and OPTN data had high concordance (n=490; Lin concordance correlation =0.90; 95% CI, 0.88 to 0.92).

CONCLUSIONS

OPTN outcomes for recipients of deceased donor kidney transplants have high validity for DGF and 6-month allograft function but lack sensitivity in detecting rejection. Future studies using OPTN data may consider focusing on allograft function at 6 months as a useful outcome.

The Incorporation of an Advanced Donation Program Into Kidney Paired Exchange: Initial Experience of the National Kidney Registry

The continued growth of kidney paired donation (KPD) to facilitate transplantation for otherwise incompatible or suboptimal living kidney donors and recipients has depended on a balance between the logistics required for patients and the collaborating transplant centers. The formation of chains for KPD and the shipping of kidneys have permitted networks such as the National Kidney Registry (NKR) to offer KPD to patients over a transcontinental area. However, over the last 3 years, we have encountered patient requests for a more flexible experience in KPD to meet their individual needs often due to rigid time constraints. To accommodate these requests, we have developed an Advanced Donation Program (ADP) in which the donor desires to donate by a specific date, but their paired recipient has not yet been matched to a specific donor or scheduled for surgery. After obtaining careful informed consent from both the donor and paired recipient, 10 KPD chains were constructed using an ADP donor. These 10 ADP donors have facilitated 47 transplants, and thus far eight of their paired recipients have received a kidney within a mean of 178 (range 10-562) days. The ADP is a viable method to support time limited donors in a KPD network.

Dopamine treatment of brain-dead Fisher rats improves renal histology but not early renal function in Lewis recipients after prolonged static cold storage

BACKGROUND

Brain death (BD) and cold preservation are major risk factors for an unfavorable transplantation outcome. Although donor dopamine treatment in brain-dead rats improves renal function and histology in allogeneic recipients, it remains to be assessed if this also holds true for the combinations of BD and prolonged static cold preservation.

METHODS

BD was induced in F344 donor rats, which were subsequently treated with NaCl 1 mL/h (BD, n = 11), NaCl/hydroxy ethyl starch (BD-norm, n = 10), or 10 μg/min/kg dopamine (BD-dopa, n = 10). Renal grafts were harvested 4 h after BD and transplanted into bilateral nephrectomized Lewis recipients 6 h after cold preservation in University of Wisconsin solution. Renal function was evaluated by use of serum creatinine and urea concentrations at days 0, 1, 3, 5, and 10. Ten days after transplantation, recipients were killed and the renal allografts were processed for light microscopy and immune histology.

RESULTS

Serum urea concentrations at days 5 and 10 were significantly lower in recipients that received a renal graft from dopamine-treated rats; for serum creatinine, only a trend was observed at day 10. Immune histology revealed a lower degree of ED1-positive cells in the donor dopamine-treated group. Under light microscopy, Banff classification revealed significantly less intimal arteritis in these grafts (P < .05).

CONCLUSIONS

Although donor dopamine treatment clearly improves renal histology in this model, the beneficial effect on early renal function was marginal. It remains to be assessed if donor dopamine treatment has a beneficial effect on renal function in long-term follow-up.

Outcomes of paired-exchange live-donor kidney transplantation: a single-center experience

INTRODUCTION

Paired-exchange kidney transplantation (PEKT) enables recipients with willing but incompatible donors to find potential matches from a larger pool of donors. It involves transportation of donor kidneys to the intended recipient with a consequent increase in the cold ischemia time (CIT).

PATIENTS AND METHODS

Our single-center study compared the outcomes of PEKT versus traditional in-center live-donor kidney transplants (ICKT). Retrospective chart review of adult patients who underwent PEKT and ICKT from January 2009 to February 2012 at our institution was performed. Delayed graft function, acute rejection rates, incidence of proteinuria, trends in serum creatinine, and graft and patient survival rates were compared between groups.

RESULTS

Baseline demographic data were similar between the PEKT group (n = 15) and the ICKT group (n = 30) except that CIT (13.1 vs 3.8 hours; P < .001) and panel reactive antibody titers (12.6% ± 22.9% vs 0.9% ± 4.9%; P = .01) were significantly higher in the PEKT group. No patient developed delayed graft function. At a median follow-up of 12.4 months (range: 2-27.5 months), graft and patient survival rates were 100% in both groups. Serial creatinine levels were similar between the groups. There were no significant differences between groups in acute rejection rates (3 of 15 vs 3 of 30) and development of proteinuria posttransplantation (8 of 15 vs 22 of 30).

CONCLUSIONS

Our study found similar outcomes between the PEKT and ICKT groups despite longer CIT and higher panel reactive antibody titers in the PEKT group. These findings support the current practice of PEKT with transporting of donor kidneys, with the resultant increase in the chances of living-donor kidney transplantation.

Increasing access to kidney transplantation in countries with limited resources: the Indian experience with kidney paired donation

According to the Indian chronic kidney disease registry, in 2010 only 2% of end stage kidney disease patients were managed with kidney transplantation, 37% were managed with dialysis and 61% were treated conservatively without renal replacement therapy. In countries like India, where a well-organized deceased donor kidney transplantation program is not available, living donor kidney transplantation is the major source of organs for kidney transplantation. The most common reason to decline a donor for directed living donation is ABO incompatibility, which eliminates up to one third of the potential living donor pool. Because access to transplantation with human leukocyte antigen (HLA)-desensitization protocols and ABO incompatible transplantation is very limited due to high costs and increased risk of infections from more intense immunosuppression, kidney paired donation (KPD) promises hope to a growing number of end stage kidney disease patients. KPD is a rapidly growing and cost-effective living donor kidney transplantation strategy for patients who are incompatible with their healthy, willing living donor. In principle, KPD is feasible for any centre that performs living donor kidney transplantation. In transplant centres with a large living donor kidney transplantation program KPD does not require extra infrastructure, decreases waiting time, avoids transplant tourism and prevents commercial trafficking. Although KPD is still underutilized in India, it has been performed more frequently in recent times. To substantially increase donor pool and transplant rates, transplant centres should work together towards a national KPD program and frame a uniform acceptable allocation policy.

Helicopter patient transportation service on the Ulleung Island, South Korea

INTRODUCTION

Despite numerous studies of helicopter emergency medical services, few reports have examined the outcomes of patients transported by helicopter across the sea from isolated islands. We analyzed helicopter transportation from the isolated Ulleung Island, which lies to the east of the South Korean mainland.

METHODS

This study included 284 patients transported from the Ulleung Island to mainland hospitals between January 2007 and March 2013. Emergency Severity Index and Injury Severity Score were calculated. Hospital stay time and flight duration was measured. Data were analyzed using Student's t-test.

RESULTS

The mean age of the patients was 53.5 years. Of the transported patients, 19.0% were visitors to the island and 29.6% were traumatically injured. The mortality rate after transportation was 11.6% (33 patients).

CONCLUSION

Helicopter transportation has been very beneficial for the treatment of emergency patients on Ulleung Island. A national level of interest and investment is required to improve this service.

Big data in organ transplantation: registries and administrative claims

The field of organ transplantation benefits from large, comprehensive, transplant-specific national data sets available to researchers. In addition to the widely used Organ Procurement and Transplantation Network (OPTN)-based registries (the United Network for Organ Sharing and Scientific Registry of Transplant Recipients data sets) and United States Renal Data System (USRDS) data sets, there are other publicly available national data sets, not specific to transplantation, which have historically been underutilized in the field of transplantation. Of particular interest are the Nationwide Inpatient Sample and State Inpatient Databases, produced by the Agency for Healthcare Research and Quality. The USRDS database provides extensive data relevant to studies of kidney transplantation. Linkage of publicly available data sets to external data sources such as private claims or pharmacy data provides further resources for registry-based research. Although these resources can transcend some limitations of OPTN-based registry data, they come with their own limitations, which must be understood to avoid biased inference. This review discusses different registry-based data sources available in the United States, as well as the proper design and conduct of registry-based research.

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.

Clinicopathological findings in non-human primate recipients of porcine renal xenografts: quantitative and qualitative evaluation of proteinuria

BACKGROUND

Immunological and histopathological features in pig-to-primate renal xenotransplantation are widely studied. Only limited data have been reported about clinicopathological findings in primate recipients of life-supporting renal xenografts. In human medicine, proteinuria represents a common complication in kidney transplantation and is associated with impaired graft survival. The detection of low molecular weight proteins of tubular origin is considered an early method for predicting potential graft rejection. In this study, the presence and the significance of quantitative and qualitative proteinuria were evaluated in xenotransplanted non-human primates in which kidney function was supported only by the transplanted organ.

METHODS

Eight bilaterally nephrectomized cynomolgus monkeys (Macaca fascicularis) were transplanted with a single kidney from α1,3-galactosyltransferase gene-knockout (GTKO) pigs transgenic for human CD39, CD55, CD59, and α1,2-fucosyltransferase. In addition to hematological and biochemical analyses, quantitative and qualitative analysis of proteinuria was evaluated by urinary protein-to-creatinine ratio (UPC ratio) and sodium dodecyl sulfate-agarose gel electrophoresis (SDS-AGE), respectively.

RESULTS

The main hematological and biochemical changes recorded after transplantation were a progressive anemia and a severe and progressive decrease in total proteins. In urine samples, the UPC ratio was low before transplantation and increased after transplantation. Similarly, SDS-AGE was negative before transplantation, but bands consistent with mixed (i.e., tubular and glomerular) proteinuria were observed in all samples collected post-transplantation.

CONCLUSIONS

The study of clinicopathological changes in cynomolgus monkey renal xenograft recipients provides a valid help in monitoring the health conditions in the post-transplant period. Moreover, the evaluation of UPC ratio and the use of SDS-AGE technique in urine samples of cynomolgus monkey renal xenograft recipients may be considered a valid, inexpensive, and less time-consuming method than more sophisticated techniques in monitoring proteinuria. Proteinuria and presence of low molecular weight (LMW) proteins were consistently found in urine after transplantation, independent of fluctuations in renal function.

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.

Ten kidney paired donation transplantation on World Kidney Day 2013: raising awareness and time to take action to increase donor pool

BACKGROUND

Kidney paired donation (KPD) is feasible for any center that performs living related donor renal transplantation (LRDRTx). Lack of awareness, counseling and participation are important hurdles in KPD patients with incompatible donors.

MATERIALS AND METHODS

This is an institutional review board approved study of 10 ESRD patients who consented to participate in the KPD transplantation at our center. All the surgeries were carried out on the same day at the same center on the occasion of World Kidney Day (WKD) (14 March 2013). All recipients had anatomic, functional and immunological similar donors.

RESULTS

KPD were performed to avoid blood group incompatibility (n = 8) or to avoid a positive crossmatch (n = 2). None of the patients experienced delayed graft function and surgical complications. At 3 month follow-up, median serum creatinine was 1 (range 0.6 to 1.25) mg/dL and two patients developed allograft biopsy-proven acute rejection and responded to antirejection therapy. Due to impact of our awareness activity, 20 more KPD patients are medically fit for transplantation and waiting for permission from the authorization committee before transplantation.

CONCLUSION

This is a report of 10 simultaneous KPD transplantations in a single day in a single centre on WKD raising awareness of KPD. KPD is viable, legal and rapidly growing modality for facilitating LRDRTx for patients who are incompatible with their healthy, willing LRD.

Kidney paired donation in the presence of donor-specific antibodies

Incompatible donor/recipient pairs with broadly sensitized recipients have difficulty finding a crossmatch-compatible match, despite a large kidney paired donation pool. One approach to this problem is to combine kidney paired donation with lower-risk crossmatch-incompatible transplantation with intravenous immunoglobulin. Whether this strategy is non-inferior compared with transplantation of sensitized patients without donor-specific antibody (DSA) is unknown. Here we used a protocol including a virtual crossmatch to identify acceptable crossmatch-incompatible donors and the administration of intravenous immunoglobulin to transplant 12 HLA-sensitized patients (median calculated panel reactive antibody 98%) with allografts from our kidney paired donation program. This group constituted the DSA(+) kidney paired donation group. We compared rates of rejection and survival between the DSA(+) kidney paired donation group with a similar group of 10 highly sensitized patients (median calculated panel reactive antibody 85%) that underwent DSA(-) kidney paired donation transplantation without intravenous immunoglobulin. At median follow-up of 22 months, the DSA(+) kidney paired donation group had patient and graft survival of 100%. Three patients in the DSA(+) kidney paired donation group experienced antibody-mediated rejection. Patient and graft survival in the DSA(-) kidney paired donation recipients was 100% at median follow-up of 18 months. No rejection occurred in the DSA(-) kidney paired donation group. Thus, our study provides a clinical framework through which kidney paired donation can be performed with acceptable outcomes across a crossmatch-incompatible transplant.

Dynamic challenges inhibiting optimal adoption of kidney paired donation: findings of a consensus conference

While kidney paired donation (KPD) enables the utilization of living donor kidneys from healthy and willing donors incompatible with their intended recipients, the strategy poses complex challenges that have limited its adoption in United States and Canada. A consensus conference was convened March 29-30, 2012 to address the dynamic challenges and complexities of KPD that inhibit optimal implementation. Stakeholders considered donor evaluation and care, histocompatibility testing, allocation algorithms, financing, geographic challenges and implementation strategies with the goal to safely maximize KPD at every transplant center. Best practices, knowledge gaps and research goals were identified and summarized in this document.

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.

Donor chimera model for tolerance induction in transplantation

Tolerance induction is the basis of a successful transplantation with the goal being the re-establishment of homeostasis after transplantation. Non-autograft transplantation disrupts this maintenance drastically which would be avoided by administration of a novel procedure. At present, the blood group antigens and the genotypes of the donor and recipient are cross-matched before transplantation combined with a drug regimen that confers general immunosuppression. But the 'specific' unresponsiveness of the recipient to the donor organ, implied by 'tolerance', is not achieved in this process. This article introduces the 'donor chimera model' via the concept of the 'closed transplantation loop' approach for tolerance induction which seeks to limit the use of immunosuppressive therapy after transplantation.