Clinical Outcomes in Kidney Transplantation Patients From Deceased Donors With Acute Kidney Injury

Short-Term, Mid-Term, and Long-Term Outcomes after Deceased Donor Kidney Transplantation in Patients with AKI: A Systematic Review and Meta-Analysis

Key Points

This study reviews the willingness to use kidneys from donors who have experienced AKI during transplantation and provides a thorough analysis of the existing literature. While delayed graft function is more common, primary nonfunction and acute rejection rates appear comparable, as do allograft function and graft survival compared with non-AKI donor kidneys. Considering the shortage of available organs and the high mortality rate of patients on dialysis, the use of donors with AKI as a source for kidney transplantation is a viable alternative.

Background

AKI is a common complication in hospitalized patients and may occur in potential kidney donors. Observational studies have suggested that kidney transplantation in patients with AKI is feasible and safe, but no systematic evaluation has been performed.

Methods

We performed a systematic review and meta-analysis to evaluate the outcomes of kidney transplantation in patients with AKI. We searched MEDLINE, Embase, Cochrane, Google Scholar, and other databases for studies reporting outcomes of donor kidneys with AKI. We included single-center, multicenter, and registry-based studies and analyzed them according to the definition and severity of AKI. End points were primary and delayed graft function (DGF), primary nonfunction (PNF), length of hospital stay, rejection, graft function, and patient and graft survival at 1, 3, 5, and 8–10 years after transplantation. This study was registered in PROSPERO, number CRD42021260088.

Results

We identified 33 single-center, four multicenter, and seven registry studies with more than 100,000 patients published between 2005 and 2022. Recipients from donors with AKI had a higher risk of DGF (relative risk, 1.51; 95% confidence interval [CI], 1.35 to 1.68). Graft function at discharge was worse in the AKI group (MDCrea [95% CI]: 0.96 mg/dl [0.36 to 1.56, I2=96%], MDGFR [95% CI]: −8.88 ml/min per 1.73 m2 [−15.32 to −2.44, I2=93%]), but improved thereafter and was similar in both groups at 3 months after transplantation (MDCrea [95% CI]: −0.05 mg/dl [−0.18 to 0.07, I2=0%], MDGFR [95% CI]: −1.83 ml/min per 1.73 m2 [−5.29 to 1.63, I2=91%]). Primary nonfunction and patient and graft survival were similar at 1, 3, 5, and 8–10 years after transplantation. There were no differences in rejections regardless of AKI definition and severity.

Conclusions

Transplantation of kidneys with AKI is associated with satisfactory short-term and long-term outcomes and should be pursued to increase the donor pool.

Kidney Transplantation From Donors With Acute Kidney Injury: Are the Concerns Justified? A Systematic Review and Meta-Analysis

Renal transplantation improves quality of life and prolongs survival in patients with end-stage kidney disease, although challenges exist due to the paucity of suitable donor organs. This has been addressed by expanding the donor pool to include AKI kidneys. We aimed to establish whether transplanting such kidneys had a detrimental effect on graft outcome. The primary aim was to define early outcomes: delayed graft function (DGF) and primary non-function (PNF). The secondary aims were to define the relationship to acute rejection, allograft survival, eGFR and length of hospital stay (LOS). A systematic literature review and meta-analysis was conducted on the studies reporting the above outcomes from PubMed, Embase, and Cochrane Library databases. This analysis included 30 studies. There is a higher risk of DGF in the AKI group (OR = 2.20, p < 0.00001). There is no difference in the risk for PNF (OR 0.99, p = 0.98), acute rejection (OR 1.29, p = 0.08), eGFR decline (p = 0.05) and prolonged LOS (p = 0.11). The odds of allograft survival are similar (OR 0.95, p = 0.54). Transplanting kidneys from donors with AKI can lead to satisfactory outcomes. This is an underutilised resource which can address organ demand.

Impact of acute kidney injury on graft outcomes of deceased donor kidney transplantation: A nationwide registry-based matched cohort study in Korea

BACKGROUND

Favorable long-term and short-term graft survival and patient survival after kidney transplantation (KT) from deceased donors with acute kidney injury (AKI) have been reported. However, few studies have evaluated effects of donor AKI status on graft outcomes after KT in Asian population. Thus, the purpose of this study was to evaluate graft function after KTs from donors with AKI compared to matched KTs from donors without AKI using a multicenter cohort in Korea.

METHODS

We analyzed a total of 1,466 KTs collected in Korean Organ Transplant Registry between April 2014 and December 2017. KTs from AKI donors (defined as donors with serum creatinine level ≥ 2 mg/dL) and non-AKI donors (275 cases for each group) were enrolled using a 1:1 propensity score matching. Graft outcomes including graft and patient survival, delayed graft function (DGF), rejection rate, and serially measured estimated glomerular filtration rate (eGFR) were evaluated.

RESULTS

After propensity matching, KTs from AKI donors showed higher rate of DGF (44.7% vs. 24.0%, p < 0.001). However, the rejection rate was not significantly different between the two groups (KTs from AKI donors vs. KTs from non-AKI donors). eGFRs measured after 6 months, 1 year, 2 years and 3 years were not significantly different by donor AKI status. With median follow-up duration of 3.52 years, cox proportional hazards models revealed hazard ratio of 0.973 (95% confidence interval [CI], 0.584 to 1.621), 1.004 (95% CI, 0.491 to 2.054) and 0.808 (95% confidence interval [CI], 0.426 to 1.532) for overall graft failure, death-censored graft failure and patient mortality, respectively, in KTs from AKI donors compared to KTs from non-AKI donors as a reference.

CONCLUSIONS

KTs from AKI donors showed comparable outcomes to KTs from non-AKI donors, despite a higher incidence of DGF. Results of this study supports the validity of using kidneys from deceased AKI donors in Asian population.

Outcomes and factors leading to graft failure in kidney transplants from deceased donors with acute kidney injury-A retrospective cohort study

Due to shortage of donor, kidney transplants (KTs) from donors with acute kidney injury (AKI) are expanding. Although previous studies comparing clinical outcomes between AKI and non-AKI donors in KTs have shown comparable results, data on high-volume analysis of KTs outcomes with AKI donors are limited. This study aimed to analyze the selection trends of AKI donors and investigate the impact of AKI on graft failure using the United states cohort data. We analyzed a total 52,757 KTs collected in the Scientific Registry of Transplant Recipient (SRTR) from 2010 to 2015. The sample included 4,962 (9.4%) cases of KTs with AKI donors (creatinine ≥ 2 mg/dL). Clinical characteristics of AKI and non-AKI donors were analyzed and outcomes of both groups were compared. We also analyzed risk factors for graft failure in AKI donor KTs. Although the incidence of delayed graft function was higher in recipients of AKI donors compared to non-AKI donors, graft and patient survival were not significantly different between the two groups. We found donor hypertension, cold ischemic time, the proportion of African American donors, and high KDPI were risk factors for graft failure in AKI donor KTs. KTs from deceased donor with AKI showed comparable outcomes. Thus, donors with AKI need to be considered more actively to expand donor pool. Caution is still needed when donors have additional risk factors of graft failure.

Impact of deceased donor with acute kidney injury on subsequent kidney transplant outcomes-an ANZDATA registry analysis

BACKGROUND

The need for kidney transplantation drives efforts to expand organ donation. The decision to accept organs from donors with acute kidney injury (AKI) can result in a clinical dilemma in the context of conflicting reports from published literature.

MATERIAL AND METHODS

This observational study included all deceased donor kidney transplants performed in Australia and New Zealand between 1997 and 2017. The association of donor-AKI, defined according to KDIGO criteria, with all-cause graft failure was evaluated by multivariable Cox regression. Secondary outcomes included death-censored graft failure, death, delayed graft function (DGF) and acute rejection.

RESULTS

The study included 10,101 recipients of kidneys from 5,774 deceased donors, of whom 1182 (12%) recipients received kidneys from 662 (11%) donors with AKI. There were 3,259 (32%) all-cause graft failures, which included 1,509 deaths with functioning graft. After adjustment for donor, recipient and transplant characteristics, donor AKI was not associated with all-cause graft failure (adjusted hazard ratio [HR] 1.11, 95% CI 0.99-1.26), death-censored graft failure (HR 1.09, 95% CI 0.92-1.28), death (HR 1.15, 95% CI 0.98-1.35) or graft failure when death was evaluated as a competing event (sub-distribution hazard ratio [sHR] 1.07, 95% CI 0.91-1.26). Donor AKI was not associated with acute rejection but was associated with DGF (adjusted odds ratio [OR] 2.27, 95% CI 1.92-2.68).

CONCLUSION

Donor AKI stage was not associated with any kidney transplant outcome, except DGF. Use of kidneys with AKI for transplantation appears to be justified.

Urine Injury Biomarkers Are Not Associated With Kidney Transplant Failure

BACKGROUND

Kidneys transplanted from deceased donors with serum creatinine-defined acute kidney injury (AKI) have similar allograft survival as non-AKI kidneys but are discarded at a higher rate. Urine injury biomarkers are sensitive markers of structural kidney damage and may more accurately predict graft outcomes.

METHODS

In the 2010-2013 multicenter Deceased Donor Study of 2430 kidney transplant recipients from 1298 donors, we assessed the association of donor urine injury biomarkers microalbumin, neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, IL-18, and liver-type fatty acid binding protein with graft failure (GF) and death-censored GF (dcGF) using Cox proportional hazard models (median follow-up 4 y). We examined if serum creatinine-defined donor AKI modified this association to assess the relationship between subclinical donor AKI (elevated biomarkers without creatinine-defined AKI) and GF. Through chart review of a subcohort (1137 recipients), we determined associations between donor injury biomarkers and a 3-year composite outcome of GF, mortality, or estimated glomerular filtration rate ≤ 20mL/min/1.73m.

RESULTS

Risk of GF, dcGF, and 3-year composite outcome did not vary with donor injury biomarker concentrations after adjusting for donor, transplant, and recipient characteristics (adjusted hazard ratio ranged from 0.96 to 1.01 per log-2 increase in biomarker). Subclinical injury in transplanted kidneys without AKI was not associated with GF.

CONCLUSIONS

AKI measured using injury biomarkers was not associated with posttransplant graft outcomes (at median 4 y posttransplant). When assessing posttransplant graft viability, clinicians can prioritize other donor and recipient factors over donor kidney injury, measured by either serum creatinine or urine injury biomarkers.

A Review of Donor Acute Kidney Injury and Posttransplant Outcomes

Although over 90 000 people are on the kidney transplant waitlist in the United States, some kidneys that are viable for transplantation are discarded. Transplant surgeons are more likely to discard deceased donors with acute kidney injury (AKI) versus without AKI (30% versus 18%). AKI is defined using changes in creatinine from baseline. Transplant surgeons can use DonorNet data, including admission, peak, and terminal serum creatinine, and biopsy data when available to differentiate kidneys with AKI from those with chronic injury. Although chronic kidney disease is associated with reduced graft survival, an abundance of literature has demonstrated similar graft survival for deceased donors with AKI versus donors without AKI. Donors with AKI are more likely to undergo delayed graft function but have similar long-term outcomes as donors without AKI. The mechanism for similar graft survival is unclear. Some hypothesized mechanisms include (1) ischemic preconditioning; (2) posttransplant and host factors playing a greater role in long-term survival than donor factors; and (3) selection bias of transplanting only relatively healthy donor kidneys with AKI. Existing literature suggests transplanting more donor kidneys with stage 1 and 2 AKI, and cautious utilization of stage 3 AKI donors, may increase the pool of viable kidneys. Doing so can reduce the number of people who die on the waitlist by over 500 every year.

An international comparison of deceased donor kidney utilization: What can the United States and the United Kingdom learn from each other?

In transplant, meaningful international comparisons in organ utilization are needed. This collaborative study between the United Kingdom (UK) and the United States (US) aimed to develop a kidney utilization metric allowing for legitimate intercountry comparisons. Data from the UK and US transplant registries, including all deceased donor kidneys recovered from 2006 to 2017, were analyzed. To identify a potentially comparable kidney utilization rate (UR), several denominators were assessed. We discovered that the proportion of transplanted kidneys from elderly donors in the UK (10.7%) was 18 times greater than that in the US (0.6%). Conversely, en bloc pediatric kidney transplant was more common in the US. Donation after circulatory death utilization has risen in both countries but is twice as prevalent in the UK (39% of transplants) vs the US (20%). In addition, US and UK URs are not directly comparable due to fundamental system differences. However, using a suite of URs revealed practice areas likely to yield the most benefit if improved, such as efforts to increase kidney offer acceptance in the US and to reduce postacceptance discard in the UK. Methods used in this study, including novel intracountry risk-adjusted UR trend logistic regression analyses, can be translated to other international transplant registries in pursuit of further global learning opportunities.

Impact of Donor Age on the Outcomes of Kidney Transplantation From Deceased Donors With Histologic Acute Kidney Injury

PURPOSE

Kidney transplantation from elderly donors with acute kidney injury (AKI) has increased recently due to donor shortage, but the safety and prognosis are not well known. We examined the effect of donor age on the outcomes of kidney transplantation (KT) from donors with histologic AKI.

MATERIALS AND METHODS

We retrospectively analyzed the medical records of 59 deceased-donor KTs with acute tubular necrosis (ATN) on preimplantation donor kidney biopsy between March 2012 and October 2017. Histologic evaluations of ATN, inflammation, glomerulosclerosis (GS), interstitial fibrosis, tubular atrophy, and arterial sclerosis were performed.

RESULTS

Twenty and 39 recipients received kidneys from elderly (> 60, 68.9 ± 5.0 years) and young (≤ 60, 45.9 ± 9.6 years) donors with ATN, respectively. Among the elderly donors, significantly increased donor creatinine was observed in only 44% donors, and there were more diabetic patients and women and a higher proportion of GS than among the young donors. Six months after KT, estimated glomerular filtration rate was significantly lower in recipients who received kidneys from elderly donors compared to young donors. Donor creatinine level and AKI severity did not significantly affect the recipient outcomes in either group. However, the presence of ATN and GS were significant factors that exacerbated renal outcomes after KT from elderly donors only. On multivariate analysis, severe ATN was the strongest independent predictor of elderly recipient renal function.

CONCLUSIONS

Histologic injury may predict renal outcomes in KT from elderly donors. A donor allocation protocol including preimplantation renal histology should be established for KT from elderly donors.

Single kidney transplantation from donors with acute kidney injury: A single-center experience

INTRODUCTION

Despite a severe shortage of organ supply, patients are reluctant to accept organs from deceased donors with AKI, let alone from pediatric AKI donors.

METHODS

We assessed 70 patients who received kidneys from donors with AKI (10 with pediatric and 60 with adult donors) and 176 contemporaneous patients who received kidneys from non-AKI donors (41 with pediatric and 135 with adult donors) between March 2012 and February 2017 for retrospectively evaluating the clinical outcomes.

RESULTS

AKI was defined and staging by the RIFLE criteria and pediatric-modified RIFLE criteria. Median age was 11.00 years IQR (4.50-14.00 years), and median weight was 25.00 kg (IQR, 17.00-45.00 kg) for all pediatric donors. Median follow-up was 8 months (range, 1-49 months). Adult AKI group had the highest incidence of DGF (35.0% vs 10%, 9.8%, and 19.3%, P = 0.011). There was a significant increase in DGF in higher AKI stages (Risk: 20.7%, Injury: 46.7%, Failure: 50.0%; P = 0.014) among patients with adult donors. No significant differences were noted in 1-year (100.0%, 95.1%, 98.3%, and 97.8%; P = 0.751) and 3-year (100.0%, 95.1%, 98.3%, and 97.8%; P = 0.751) patient survival, and 1-year (90.0%, 97.6%, 98.3%, and 95.6%; P = 0.535) and 3-year (90.0%, 97.6%, 98.3%, and 95.6%; P = 0.535) graft survival.

CONCLUSION

Transplants procured from donors with AKI, particularly pediatric ones, could achieve excellent intermediate-term clinical outcomes and thus potentially expand the donor pool.

Successful transplantation of kidneys from deceased donors with terminal acute kidney injury

BACKGROUND

There are many doubts with regards to accepting deceased kidneys with acute kidney injury (AKI) for transplantation.

PURPOSE

The aim of this study was to present the 5-years outcome of kidney transplantation cases where deceased donors developed AKI before organ procurement.

METHODS

Two hundred twenty-six deceased renal transplants were analyzed. Data regarding donors and recipients were collected. Terminal AKI was defined as terminal serum creatinine concentration higher than 1.99 mg/dL and 66 such cases were diagnosed. All kidney transplant recipients were followed for 60 months.

RESULTS

AKI group presented more episodes of delayed graft function (DGF) compared to the non-AKI group (56% vs 35%, p < .05). No differences were observed between the groups in the rate of acute rejection episodes, kidney function as well as patient and graft survival.

CONCLUSIONS

Transplants with AKI present more often DGF and comparable graft survival to transplants without AKI. Kidneys with AKI can be a valuable source of organs provided attentive selection and appropriate care of deceased donors.

Impact of acute kidney injury in donors on renal graft survival: a systematic review and Meta-Analysis

The acute kidney injury (AKI) of deceased donors was an important strategy to address donor shortage. This meta-analysis was conducted to explore the clinical effect of kidney transplantation from donors with AKI. PubMed, Embase, and Cochrane Library were searched through July 2017. Fourteen cohort studies, involving a total of 15,345 donors, were included. Studies were pooled, and the hazard ratio (HR), relative risk (RR), weighted mean difference (WMD), and their corresponding 95% confidence interval (CI) were calculated. The present meta-analysis showed no significant difference in allograft survival between the AKI and non-AKI groups (HR = 1.16, 95% CI = 0.99–1.37, P_{heterogeneity} = 0.238, I² = 21.6%) from 12 months to 120 months after kidney transplantation. However, the time of hospital stay was significantly longer (WMD = 2.49, 95% CI = 1.06–3.92, P_{heterogeneity} = 0.458, I² = 0%) and the incidence of delayed graft function (DGF) was significantly higher (RR = 1.76, 95% CI = 1.52–2.04, P_{heterogeneity} < 0.001, I² = 71.2%) in the AKI group than in the non-AKI group. We concluded that even though hospital stay time was longer and the incidence of DGF was significantly higher in the AKI group, there is no significant difference in allograft survival between the two groups.

Success of kidney transplantations from deceased donors with acute kidney injury

Background

The acceptance of organs from deceased donors with acute kidney injury (AKI) varies considerably, with uncertain outcomes. The current organ shortage has led to increased use of marginal donor organs.

Material/Methods

This retrospective, single-center study included 642 patients who underwent kidney allograft transplantation between 2005 and 2016. The recipients were categorized into 3 groups: AKI-1 (n=214), comprising donors with a peak serum creatinine (SCr) level of 1.1–2.0 mg/dl; AKI-2 (n=89), comprising donors with a peak SCr level >2 mg/dl; and non-AKI (n=339), comprising donors with normal kidney function (SCr <1.1 mg/dl).

Results

The cumulative survival rates for patients and grafts did not significantly differ among the AKI-1, AKI-2, and non-AKI groups at the 1-year (91.6%/79.4%, 92.1%/83.1%, 95.3%/88.5%, respectively) and 5-year assessments (79.4%/67.8%, 86.8%/71.7%, 80.5%/71.1%, respectively). These findings were corroborated by mean SCr values and estimated glomerular filtration rates at the 1-year (2.08±1.7/51.16±23.45, 2.01±1.52/56.46±23.63, 1.81±1.13/ 55.44±23.26 mg/dl, respectively) and 5-year assessments (1.91±1.28/51.06±24.65, 1.74±0.66/57.44±31.21, 1.7±0.88/ 58.56±26.04 mg/dl, respectively). The incidence of delayed graft function in each group was 29.9%, 44.9%, and 28.6%, respectively.

Conclusions

Kidney transplantation from donors with AKI, although associated with a higher rate of delayed graft function, results in good long-term transplant survival and reliable kidney functionality after 5 years. The inclusion of donors with AKI may widely extend the pool of available organs; however, careful donor selection is necessary.

Deceased-donor acute kidney injury is not associated with kidney allograft failure

Deceased-donor acute kidney injury (AKI) is associated with organ discard and delayed graft function, but data on longer-term allograft survival are limited. We performed a multicenter study to determine associations between donor AKI (from none to severe based on AKI Network stages) and all-cause graft failure, adjusting for donor, transplant, and recipient factors. We examined whether any of the following factors modified the relationship between donor AKI and graft survival: kidney donor profile index, cold ischemia time, donation after cardiac death, expanded-criteria donation, kidney machine perfusion, donor-recipient gender combinations, or delayed graft function. We also evaluated the association between donor AKI and a 3-year composite outcome of all-cause graft failure or estimated glomerular filtration rate ≤ 20 mL/min/1.73 m² in a subcohort of 30% of recipients. Among 2,430 kidneys transplanted from 1,298 deceased donors, 585 (24%) were from donors with AKI. Over a median follow-up of 4.0 years, there were no significant differences in graft survival by donor AKI stage. We found no evidence that pre-specified variables modified the effect of donor AKI on graft survival. In the subcohort, donor AKI was not associated with the 3-year composite outcome. Donor AKI was not associated with graft failure in this well-phenotyped cohort. Given the organ shortage, the transplant community should consider measures to increase utilization of kidneys from deceased donors with AKI.

Kidney transplantation using expanded criteria deceased donors with terminal acute kidney injury: a single center experience in Korea

Purpose

We investigated the clinical outcomes of deceased donor kidney transplantation (KT) using kidneys with terminal acute kidney injury (AKI).

Methods

Between February 2000 and December 2013, we performed 202 deceased donor renal transplants from 159 brain dead donors. According to the expanded criteria donor (ECD) and AKI network criteria, we divided 202 recipients into 4 groups: Group I: Non-AKI & standard criteria donor (SCD) (n = 97); group II: Non-AKI & ECD (n = 15); group III: AKI & SCD (n = 52); and group IV: AKI & ECD (n = 38).

Results

The incidence of delayed graft function (DFG) was significantly higher in patients with AKI than it was in the non-AKI group (P = 0.008). There were no significant differences among the 4 groups in graft survival (P = 0.074) or patient survival (P = 0.090). However, the long-term allograft survival rate was significantly lower in group IV than it was in other groups (P = 0.024).

Conclusion

Allografts from deceased donors with terminal AKI had a higher incidence of DGF than did those from donors without AKI. However, there is no significant difference in graft and patient survival rates among the groups. So, the utilization of renal grafts from ECDs with terminal AKI is a feasible approach to address the critical organ shortage.

Kidney Donor Risk Index as the Predictor for the Short-term Clinical Outcomes After Kidney Transplant From Deceased Donor With Acute Kidney Injury

BACKGROUND

The Kidney Donor Risk Index (KDRI) scoring system for deceased donors has been widely introduced for postoperative evaluation of graft function. We analyzed the usefulness of the KDRI in deceased donors with acute kidney injury (AKI).

METHODS

Forty-nine recipients from deceased donors with AKI between January 2009 and December 2014 were reviewed retrospectively. Data collected from donor medical records included age, height, weight, hypertension or diabetes history, cause of death, serum creatinine (sCr), and donation after cardiac death. Graft function data including sCr, estimated glomerular filtration rate (eGFR), and acute rejection episodes were monitored for 1 year. Correlations between KDRI score and factors indicating graft function were analyzed. A cutoff value for KDRI score was calculated using a receiver operating characteristic (ROC) curve for significant graft function.

RESULTS

The mean ages of donors and recipients were 46.81 ± 13.13 and 47.69 ± 11.43, respectively. The mean KDRI score was 1.24 ± 0.40. Univariable analysis of KDRI score and factors indicating graft function indicated that sCr at 6 to 12 months, eGFR at 1 year, and slow graft function (SGF) had statistical significance. The ROC curve of KDRI score for SGF showed an optimal cutoff value of 1.20, with sensitivity of 69.2% and specificity of 69.4% (area under the curve = 0.75) in deceased donors with AKI.

CONCLUSIONS

KDRI score in deceased donors with AKI was correlated with postoperative graft values including eGFR and SGF. KDRI could be used as a predictor for the short-term clinical outcome after kidney transplant from deceased donor with AKI.

Prediction of clinical outcomes after kidney transplantation from deceased donors with acute kidney injury: a comparison of the KDIGO and AKIN criteria

Background

Acute kidney injury (AKI) is frequently detected in deceased donors (DDs), and it could be associated with adverse clinical outcomes in corresponding kidney transplant recipients (KTRs). In this regard, we sought to identify which criteria is better between the KDIGO and AKIN criteria for the diagnosis of AKI in DDs in the prediction of clinical outcomes after kidney transplantation (KT).

Methods

Two hundred eighty-five cases of deceased donor kidney transplantation (DDKT) were included. We divided them into three groups; the non-AKI by both KDIGO and AKIN criteria group (n = 120), the AKI by KDIGO only group (n = 61), and the AKI by both criteria group (n = 104) according to the diagnosis of AKI using the KDIGO and AKIN criteria in the corresponding 205 DDs. We compared the development of delayed graft function (DGF), the change in allograft function, the allograft survival among the three groups.

Results

The incidence of DGF was significantly higher in the AKI by KDIGO only and the AKI by both criteria groups than in the non-AKI by both criteria group (P < 0.05 each). But no difference was detected between the AKI by KDIGO only group and the AKI by both criteria group (P > 0.05). Therefore, the KDIGO criteria had a better predictive value for DGF occurrence than the AKIN criteria (Area under the curve = 0.72 versus 0.63, P < 0.05) in Receiver Operation Characteristic analysis. On comparison of allograft function, the AKI by KDIGO only and the AKI by both criteria groups showed a significantly deteriorating pattern by 6 months after KT in comparison with the non-AKI by both criteria group (P < 0.05). However, the differences disappeared at 1 year from KT and long-term allograft survival did not differ among the three groups. AKI stage either by KDIGO or AKIN in DDs did not affect long-term allograft survival in corresponding KTRs as well.

Conclusions

The KDIGO criteria may be more useful for predicting DGF than the AKIN criteria. However, AKI or AKI stage by either criteria in DDs failed to affect long-term allograft outcomes in KTRs.

Associations of deceased donor kidney injury with kidney discard and function after transplantation

Deceased donor kidneys with acute kidney injury (AKI) are often discarded due to fear of poor outcomes. We performed a multicenter study to determine associations of AKI (increasing admission-to-terminal serum creatinine by AKI Network stages) with kidney discard, delayed graft function (DGF) and 6-month estimated glomerular filtration rate (eGFR). In 1632 donors, kidney discard risk increased for AKI stages 1, 2 and 3 (compared to no AKI) with adjusted relative risks of 1.28 (1.08-1.52), 1.82 (1.45-2.30) and 2.74 (2.0-3.75), respectively. Adjusted relative risk for DGF also increased by donor AKI stage: 1.27 (1.09-1.49), 1.70 (1.37-2.12) and 2.25 (1.74-2.91), respectively. Six-month eGFR, however, was similar across AKI categories but was lower for recipients with DGF (48 [interquartile range: 31-61] vs. 58 [45-75] ml/min/1.73m(2) for no DGF, p < 0.001). There was significant favorable interaction between donor AKI and DGF such that 6-month eGFR was progressively better for DGF kidneys with increasing donor AKI (46 [29-60], 49 [32-64], 52 [36-59] and 58 [39-71] ml/min/1.73m(2) for no AKI, stage 1, 2 and 3, respectively; interaction p = 0.05). Donor AKI is associated with kidney discard and DGF, but given acceptable 6-month allograft function, clinicians should consider cautious expansion into this donor pool.