Donor acute kidney injury and short-term graft outcome in renal transplantation

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.

MicroRNA-192-5p downregulates Fat Mass and Obesity-associated Protein to aggravate renal ischemia/reperfusion injury

Acute kidney injury (AKI) is a common disorder without effective therapy yet. Renal ischemia/reperfusion (I/R) injury is a common cause of AKI. MicroRNA miR-192-5p has been previously reported to be upregulated in AKI models. However, its functional role in renal I/R injury is not fully understood. This study aimed to investigate the effects and the underlying mechanism of miR-192-5p in renal I/R progression. Hypoxia/reoxygenation (H/R)-induced cell injury model in HK-2 cells and I/R-induced renal injury model in mice were established in this study. Cell counting kit-8 assay was performed to determine cell viability. Quantitative real-time PCR and western blot analysis were performed to detect gene expressions. Hematoxylin-eosin and periodic acid-Schiff staining were performed to observe the histopathological changes. Enzyme-linked immunosorbent assay was performed to detect the kidney markers' expression. In vivo and in vitro results showed that miR-192-5p was up-regulated in the I/R-induced mice model and H/R-induced cell model, and miR-192-5p overexpression exacerbated I/R-induced renal damage. Then, the downstream target of miR-192-5p was analyzed by combining the differentially expressed mRNAs and the predicted genes and confirmed using a dual-luciferase reporter assay. It was found that miR-192-5p was found to regulate fat mass and obesity-associated (FTO) protein expression by directly targeting the 3' untranslated region of FTO mRNA. Moreover, in vivo and in vitro studies unveiled that FTO overexpression alleviated renal I/R injury and promoted HK-2 cell viability via stimulating autophagy flux. In conclusion, miR-192-5p aggravated I/R-induced renal injury by blocking autophagy flux via down-regulating FTO.

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.

Deceased Donor Kidney Transplantation From Donors With Acute Kidney Injury: Realities and Costs

OBJECTIVES

Transplant of kidneys from donors with acute kidney injury has shown favorable outcomes. We investigated the outcomes of kidney transplant recipients with deceased donors who developed acute kidney injury before organ procurement.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of recipients from January 2016 to December 2021 in a single center. Outcomes in recipients of kidney grafts from donors with and without acute kidney injury were compared.

RESULTS

The mean follow-up time was 40 months. Our study included 129 (34%) kidneys transplanted from donors with acute kidney injury and 251 (66%) kidneys from donors without acute kidney injury. Delayed graft function rate in recipients was 33% in the acute kidney injury group and 25.5% in the group without acute kidney injury (P = .099). Readmission rate at 30 days was significantly higher among recipients of kidneys with acute kidney injury compared with recipients of kidneys without acute kidney injury (45% vs 33.5%; P = .02). The mean overall costs of transplant in the acute kidney injury group were comparable to the group without acute kidney injury ($253 865 vs $253 611; P = .97). The acute rejection rate was comparable between the 2 groups (4% in both groups; P = .96). Delayed graft function rate was increased with increased stage of acute kidney injury (18% stage 1, 45% stage 2, 36% stage 3; P = .03). However, the overall length of hospital stay and costs were comparable among recipients of different stages of acute kidney injury.

CONCLUSIONS

Our study showed that kidney transplants from donors with acute kidney injury have early and late outcomes comparable to kidney transplants from donors without acute kidney injury. Allografts from donors with acute kidney injury can be used safely and can expand the donor pool in kidney transplant without increasing perioperative resource utilization.

The benefits of initiating continuous renal replacement therapy after brain death in organ donors with oligoanuric acute kidney injury

Acute kidney injury (AKI) in deceased organ donors is increasing due to the escalation in anoxic brain-deaths. The management of an organ donor with oligoanuric AKI is frequently curtailed due to hemodynamic and electrolyte instability. Although continuous renal replacement therapy (CRRT) corrects the effects of AKI, it is rarely started after the diagnosis of brain-death (BD). Since 2017, we have initiated CRRT in organ donors with oligoanuric AKI to allow more time to stabilize the donor and improve the function of the thoracic organs. We now report our experience with the first 27 donors with oligoanuric AKI that received CRRT after the diagnosis of BD, with organs transplanted as the primary outcome. The average duration of CRRT was 30.1±14.4 hours and the mean ultrafiltration volume was 5,141±4,272 milliliters. The time from BD declaration to cross clamp was significantly longer in the CRRT group versus a historical cohort with oligoanuric AKI that was not dialyzed (62.8±18.3 vs 37.1±14.9 hours; p<0.01) The mean number of total organs transplanted per donor in the CRRT group was greater than the historical cohort, 2.9±1.7 vs 1.4±0.6 (p = 0.<01), respectively. The mean number of thoracic organs transplanted per donor also increased between the two groups, 1.4±1.2 vs 0.6±0.9 (p = 0.02). Thirty-seven percent of the kidneys were successfully transplanted with a mean serum creatinine of 1.4 mg/dL at six months. We suggest that OPOs consider starting CRRT in organ donors with oligoanuric AKI to possibly increase the number of organs transplanted. This article is protected by copyright. All rights reserved.

Outcome of kidney transplantations from ≥65-year-old deceased donors with acute kidney injury

Kidney transplantation (KT) from donors with acute kidney injury (AKI) has been associated with delayed graft function (DGF) but similar graft survival compared with KT from donors without AKI. Kidneys from ≥65-year-old donors with comorbidities are more susceptible to cold ischemia time and DGF and it is unknown whether such elderly kidneys with AKI can also be transplanted with satisfactory outcomes. All KTs from ≥65-year-old donors performed at our centre from 1999 to 2019 (n = 233) were retrospectively analysed and short- as well as long-term outcomes were compared for KTs from donors with (n = 64) and without AKI (n = 169). There were no significant differences regarding the frequency of DGF as well as the estimated glomerular filtration rate (eGFR) one and three years post-transplant between the no-AKI and the AKI group (DGF: no-AKI 30.2% vs. AKI 40.6%, P = 0.17; eGFR at one-year: 31.9 ml/min/1.73m² vs. 35.5 ml/min/1.73m² , P = 0.32; at three-years: 33.8 ml/min/1.73m² vs. 40.9 ml/min/1.73m² , P = 0.18; respectively). Death-censored graft survival and patient survival were also not significantly different. Multivariable Cox regression analysis did not identify AKI as a significant risk factor for graft loss or death. Following careful donor and recipient selection, kidneys from ≥65-year-old AKI donors may potentially be transplanted with satisfactory outcomes. This article is protected by copyright. All rights reserved.

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.

MicroRNA-27a-3p aggravates renal ischemia/reperfusion injury by promoting oxidative stress via targeting growth factor receptor-bound protein 2

Renal ischemia-reperfusion (RI/R) injury with high morbidity and mortality is one common clinical disease. Development of drug targets to treat the disorder is critical important. MiR-27a-3p plays important roles in regulating oxidative stress. However, its effects on RI/R injury have not been reported. In this paper, hypoxia/reoxygenation (H/R) models on NRK-52E and HK-2 cells, and RI/R model in C57BL/6 mice were established. The results showed that H/R in vitro decreased cell viability and increased ROS levels in cells, and RI/R caused renal injury and oxidative damage in mice. The expression levels of miR-27a-3p were up-regulated based on real-time PCR and FISH assays in model groups compared with control groups, which directly targeted Grb2 based on dual luciferase reporter assay and co-transfaction test. In addition, miR-27a- 3p markedly reduced Grb2 expression to down-regulate the expression levels of p-PI3K, p-AKT, Nrf2, HO-1, and up-regulate Keap1 expression in model groups. MiR-27a-3p mimics in vitro enhanced H/R-caused oxidative stress via increasing ROS levels and decreasing Grb2 expression to down-regulate PI3K-AKT signal. In contrary, miR-27a-3p inhibitor in vitro significantly reduced H/R-caused oxidative damage via decreasing ROS levels and increasing Grb2 expression to up-regulate PI3K-AKT signal. In vivo, miR-27a- 3p agomir exacerbated RI/R-caused renal damage by decreasing SOD level and increasing Cr, BUN, MDA levels via suppressing Grb2 expression to down-regulate PI3K- AKT signal. However, miR-27a -3p antagomir alleviated RI/R-caused oxidative damage via increasing Grb2 expression to up-regulate PI3k-AKT signal. Grb2siRNA in mice further enhanced RI/R-caused renal injury by increasing Cr, BUN, MDA levels and decreasing SOD level via inhibiting the expression levels of Grb2, Nrf2, HO-1, and increasing Keap1 expression. Our data showed that miR-27a-3p aggravated RI/R injury by promoting oxidative stress via targeting Grb2, which should be considered as one new drug target to treat RI/R injury.

Association of Deceased Donor Acute Kidney Injury With Recipient Graft Survival

IMPORTANCE

The shortage of deceased donor kidneys for transplants is an ongoing concern. Prior studies support transplanting kidneys from deceased donors with acute kidney injury (AKI), but those investigations have been subject to selection bias and small sample sizes. Current allocation practices of AKI kidneys in the United States are not well characterized.

OBJECTIVES

To evaluate the association of deceased donor AKI with recipient graft survival and to characterize recovery and discard practices for AKI kidneys by organ procurement organizations.

DESIGN, SETTING, AND PARTICIPANTS

Registry-based, propensity score-matched cohort study from January 1, 2010, to December 31, 2013, in the United States. The dates of analysis were March 1 to November 1, 2019. From 2010 to 2013, a total of 6832 deceased donors with AKI and 15 310 deceased donors without AKI had at least 1 kidney transplanted. This study used a 1:1, propensity score-matched analysis to match deceased donors with AKI to deceased donors without AKI and investigated outcomes in their corresponding kidney recipients.

EXPOSURE

Deceased donor AKI, defined as at least 50% or 0.3-mg/dL increase in terminal serum creatinine level from admission.

MAIN OUTCOMES AND MEASURES

Recipients were assessed for the time to death-censored graft failure and the following secondary outcomes: delayed graft function, primary nonfunction, and the time to all-cause graft failure.

RESULTS

Ninety-eight percent (6722 of 6832) of deceased donors with AKI were matched to deceased donors without AKI. The mean (SD) age of the 13 444 deceased donors was 40.4 (14.4) years, and 63% (8529 of 13 444) were male. A total of 25 323 recipients were analyzed (15 485 [61%] were male), and their mean (SD) age was 52.0 (14.7) years. Recipients were followed up for a median of 5 (interquartile range, 4-6) years. Deceased donor AKI status had no association with death-censored graft failure (hazard ratio, 1.01; 95% CI, 0.95-1.08) or all-cause graft failure (hazard ratio, 0.97; 95% CI, 0.93-1.02). The results were consistent after examining by AKI stage and adjusting for recipient and transplant characteristics. More recipients of AKI kidneys developed delayed graft function (29% vs 22%, P < .001). Few recipients (120 of 25 323 [0.5%]) developed primary nonfunction regardless of deceased donor AKI status. Recovery and transplantation of AKI kidneys varied by organ procurement organization; most (39 of 58) had high recovery and high discard of AKI kidneys.

CONCLUSIONS AND RELEVANCE

Deceased donor AKI kidneys transplanted in the study period had recipient graft survival comparable to that of non-AKI kidneys. This study's findings suggest that the transplant community should evaluate whether currently discarded AKI kidneys from donors without substantial comorbidities can be used more effectively.

Factors of Acute Kidney Injury Donors Affecting Outcomes of Kidney Transplantation From Deceased Donors

BACKGROUND

This study aimed to investigate the outcomes of kidney transplantation (KT) from deceased acute kidney injury (AKI) donors and analyzed the factors affecting these outcomes.

METHODS

All patients who underwent KT from deceased donors at our institution from 1998 to 2016 were retrospectively reviewed. Recipients were divided into the AKI and non-AKI donor groups. We analyzed delayed graft function (DGF), serum creatinine levels at 1 month and 1 year after KT, cold ischemia time, donors' initial and terminal serum creatinine levels, Kidney Donor Profile Index, and patient and graft survival in each group.

RESULTS

Of 181 recipients, 30 received kidneys from 21 AKI donors, whereas the remaining 151 received kidneys from donors without AKI. DGF more frequently developed in the AKI donor group than in the non-AKI donor group (40% vs 7.28%; P = .001). Allograft functions at 1 month and 1 year after KT did not differ between the AKI and non-AKI donor groups (1 month: P = .469; 1 year: P = .691). Factors affecting DGF were recipient weight and donor AKI. Recipient factors affecting graft function at 1 year were recipient height, length of hospital stay, serum creatinine levels at 1 month and 6 months, and biopsy-proven acute rejection. Older donor age was the only donor factor that affected graft function at 1 year.

CONCLUSION

KT from deceased AKI donors showed a higher DGF rate but favorable patient and graft survival and graft functions. Donor AKI and recipient weight affected DGF, and only older donor age affected graft function at 1 year.

Frequency and outcomes of kidney donation from intensive care patients with acute renal failure requiring renal replacement therapy

BACKGROUND

Kidney transplantation is the preferred treatment for end-stage renal failure. Unfortunately, donor organ shortages prevent many individuals receiving a renal transplant and there is a need to increase the pool of appropriate donors. The presence of acute kidney injury (AKI) in deceased donors has traditionally been a relative contraindication to renal transplantation, even though renal recovery may be favorable in the absence of chronic renal disease.

METHODS

We undertook an 8 years retrospective observational study of potential deceased organ donors with AKI requiring renal replacement therapy (RRT). We evaluated the rate of successful transplantation as well as short term and outcomes at a median of 19.5 (13.0-52.7) months after donation.

RESULTS

Amongst 1058 consented potential organ donors, 39 patients had AKI requiring RRT, of which 19 became donors (13 not medically suitable, 7 did not proceed to donation). The median (interquartile range (IQR)) donor age was 41 (34-50) years and norepinephrine, epinephrine and vasopressin were given to 18, 14 and 9 donors, respectively. From the 38 donated kidneys 34 were transplanted. The median (IQR) age of recipients was 53 (42.8-58.5) years and they were dialysis free in a median (IQR) of 5.5 (2.3-10.8) days. Only minor abnormalities were found at 3 and 6 months renal biopsies, and two patients experienced graft failure in the first 12 months.

CONCLUSION

Amongst deceased donors with AKI receiving RRT and vasoactive medications outcomes of renal transplantation seems acceptable in the absence of pre-existing renal failure and other donor co-morbidity. Such patients may be an important additional source of kidney donation.

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.

Expanding the donor pool in kidney transplantation: Should organs with acute kidney injury be accepted?-A retrospective study

BACKGROUND

Given the gap between patients in need of a renal transplantation (RTx) and organs available, transplantation centers increasingly accept organs of suboptimal quality, e.g. from donors with acute kidney injury (AKI).

METHODS

To determine the outcome of kidney transplants from deceased donors with AKI (defined as ≥ AKIN stage 1), all 107 patients who received a RTx from donors with AKI between August 2004 and July 2014 at our center were compared to their respective consecutively transplanted patients receiving kidneys from donors without AKI. 5-year patient and graft survival, frequencies of delayed graft function (DGF), acute rejections and glomerular filtration rate (eGFR, CKD-EPI) were assessed.

RESULTS

Patient survival was similar in both groups, whereas death-censored and overall graft survival were decreased in AKI kidney recipients. AKI kidney recipients showed higher frequencies of DGF and had a reduced eGFR at 7 days, three months and one and three years after RTx. However, mortality was noticeably lower compared to waiting list candidates. Rejection-free survival was similar between groups.

CONCLUSIONS

In our cohort, both short-term and long-term renal function was inferior in recipients of AKI kidneys, while patient survival was similar. Our data indicates that recipients of donor AKI kidneys should be carefully selected and additional factors impairing short- and long-term outcome should be minimized to prevent further deterioration of graft function.

Histopathology and Long-Term Outcome of Kidneys Transplanted From Donors With Severe Acute Kidney Injury

Background:

Acute kidney injury is a treatable entity although difficult to recognize without diagnostic biopsy. We investigated the potential association between clinically defined deceased donors and acute kidney injury with preimplantation histological findings and recipient outcomes.

Methods:

Kidney biopsies from donors were classified using the Acute Kidney Injury Network criteria and assessed for percentage glomerulosclerosis, tubular atrophy, interstitial fibrosis, and vascular narrowing with the Remuzzi score and for acute tubular necrosis. Differences in incidence rates of delayed graft function (DGF) and cumulative rejection episodes were compared between recipients transplanted with normal and 3 levels of acute kidney injury using the analysis of variance with Bonferroni correction ( P = .0012).

Results:

Sixteen out of 335 donors showed a severe acute kidney injury level 3 with a median serum creatinine of 458 µmol/L. Fourteen (88%) had 0-3 Remuzzi score and were used for single kidney transplantation and 2 (12%) were used for dual kidney transplantation (score: 4-6). Recipients who received a kidney from a donor with level 3 acute kidney injury had a higher percentage of DGF (47%) without statistical significance ( P = .008). The rate of cumulative rejection (45%) at 2 years was not significantly increased ( P = .09).

Conclusions:

Recipients receiving level 3 acute kidney injury kidneys, selected with Remuzzi histopathological score and acute tubular necrosis assessment, had a greater incidence of DGF but a similar long-term cumulative rejection compared to no injury and level 1 and level 2 acute kidney injury donors. The application of the histopathological examination allowed expansion of the kidney donor pool.

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.

Is prolonged cold ischemia a contraindication to using kidneys from acute kidney injury donors?

To determine the impact of prolonged cold ischemia time (CIT) on the outcome of acute kidney injury (AKI) renal grafts, we therefore performed a single-center retrospective analysis in adult patients receiving kidney transplantation (KT) from AKI donors. Outcomes were stratified according to duration of CIT. A total of 118 patients receiving AKI grafts were enrolled. Based on CIT, patients were stratified as follows: (i) <20 hours, 27 patients; (ii) 20-30 hours, 52 patients; (iii) 30-40 hours, 30 patients; (iv) ≥40 hours, nine patients. The overall incidence of delayed graft function DGF was 41.5%. According to increasing CIT category, DGF rates were 30%, 42%, 40%, and 78%, respectively (P = .03). With a mean follow-up of 48 months, overall patient and graft survival rates were 91% and 81%. Death-censored graft survival (DCGS) rates were 84% and 88% for patients with and without DGF (P = NS). DCGS rates were 92% in patients with CIT <20 hours compared to 85% with CIT >20 hours (P = NS). In the nine patients with CIT >40 hours, the 4-year DCGS rate was 100%. We conclude that prolonged CIT in AKI grafts may not adversely influence outcomes and so discard of AKI kidneys because of projected long CIT is not warranted when donors are wisely triaged.

The Need for New Donor Stratification to Predict Graft Survival in Deceased Donor Kidney Transplantation

PURPOSE

The aim of this study was to determine whether stratification of deceased donors by the United Network for Organ Sharing (UNOS) criteria negatively impacts graft survival.

MATERIALS AND METHODS

We retrospectively reviewed deceased donor and recipient pretransplant variables of kidney transplantations that occurred between February 1995 and December 2009. We compared clinical outcomes between standard criteria donors (SCDs) and expanded criteria donors (ECDs).

RESULTS

The deceased donors consisted of 369 patients. A total of 494 transplant recipients were enrolled in this study. Mean age was 41.7±11.4 year (range 18-69) and 273 patients (55.4%) were male. Mean duration of follow-up was 8.8±4.9 years. The recipients from ECD kidneys were 63 patients (12.8%). The overall mean cold ischemia time was 5.7±3.2 hours. Estimated glomerular filtration rate at 1, 2, and 3 years after transplantation were significantly lower in ECD transplants (1 year, 62.2±17.6 vs. 51.0±16.4, p<0.001; 2 year, 62.2±17.6 vs. 51.0±16.4, p=0.001; 3 year, 60.9±23.5 vs. 54.1±18.7, p=0.047). In multivariate analysis, donor age (≥40 years) was an independent risk factor for graft failure. In Kaplan-Meier analyses, there was no significant difference in death-censored graft survival (Log rank test, p>0.05), although patient survival was lower in ECDs than SCDs (Log rank test, p=0.011).

CONCLUSION

Our data demonstrate that stratification by the UNOS criteria does not predict graft survival. In order to expand the donor pool, new criteria for standard/expanded donors need to be modified by regional differences.

Excellent graft and patient survival after renal transplantation from donors after brain death with acute kidney injury: a case-control study

BACKGROUND

Whether organs from donors after brain death (DBD) with acute kidney injury (AKI) should be accepted for transplantation is still a matter of debate.

METHODS

This was a retrospective, center-based, matched cohort study of 33 renal transplant patients who received a renal allograft from a DBD with AKI. Sixty-five kidney transplants without donor AKI transplanted directly before and after the index transplantation served as controls.

RESULTS

All AKI donors were classified according to RIFLE criteria: 9.1 % Risk, 54.6 % Injury, and 36.4 % Failure. Mean serum creatinine was 2.41 ± 0.88 mg/dL at procurement and 1.06 ± 0.32 mg/dL on admission. AKI donors had lower 24-h urine production (3.22 ± 1.95 vs. 4.59 ± 2.53 L, p = 0.009) and received more frequently noradrenaline (93.9 vs. 72.3 %, p = 0.02) and/or adrenaline (15.2 vs. 1.5 %, p = 0.02). Recipient and transplant characteristics were similar except a more favorable HLA match in control patients (p = 0.01). Hemodialysis posttransplant was more frequently used in AKI recipients (14/33 [42.4 %] vs. 18/65 [27.7 %], p = 0.17). While significant elevations in serum creatinine were noted in these patients until 10 days after transplantation, this difference lost statistical significance by day 14. One-year graft survival was very similar when comparing the groups (93.6 % [95 % CI 76.8-98.4 %] vs. 90.3 % [95 % CI 79.6-95.5 %], log rank p = 0.58).

CONCLUSIONS

Kidneys from AKI donors can be transplanted with excellent intermediate prognosis and should not be discarded.

Influence of Deceased Donor and Pretransplant Recipient Parameters on Early Overall Kidney Graft-Survival in Germany

Background. Scarcity of grafts for kidney transplantation (KTX) caused an increased consideration of deceased donors with substantial risk factors. There is no agreement on which ones are detrimental for overall graft-survival. Therefore, we investigated in a nationwide multicentre study the impact of donor and recipient related risks known before KTX on graft-survival based on the original data used for allocation and graft acceptance. Methods. A nationwide deidentified multicenter study-database was created of data concerning kidneys donated and transplanted in Germany between 2006 and 2008 as provided by the national organ procurement organization (Deutsche Stiftung Organtransplantation) and BQS Institute. Multiple Cox regression (significance level 5%, hazard ratio [95% CI]) was conducted (n = 4411, isolated KTX). Results. Risk factors associated with graft-survival were donor age (1.020 [1.013-1.027] per year), donor size (0.985 [0.977-0.993] per cm), donor's creatinine at admission (1.002 [1.001-1.004] per µmol/L), donor treatment with catecholamine (0.757 [0.635-0.901]), and reduced graft-quality at procurement (1.549 [1.217-1.973]), as well as recipient age (1.012 [1.003-1.021] per year), actual panel reactive antibodies (1.007 [1.002-1.011] per percent), retransplantation (1.850 [1.484-2.306]), recipient's cardiovascular comorbidity (1.436 [1.212-1.701]), and use of IL2-receptor antibodies for induction (0.741 [0.619-0.887]). Conclusion. Some donor characteristics persist to impact graft-survival (e.g., age) while the effect of others could be mitigated by elaborate donor-recipient match and care.