Duration of delayed graft function and outcomes after kidney transplantation from controlled donation after circulatory death donors: a retrospective study

The impact of the duration of delayed graft function (DGF) on graft survival is poorly characterized in controlled donation after circulatory death (DCD) donor kidney transplantation. A retrospective analysis was performed on 225 DCD donor kidney transplants between 2011 and 2016. When patients with primary nonfunction were excluded (n = 9), 141 recipients (65%) had DGF, with median (IQR) duration of dialysis dependency of 6 (2–11.75) days. Longer duration of dialysis dependency was associated with lower estimated glomerular filtration rate at 1 year, and a higher rate of acute rejection. On Kaplan–Meier analysis, the presence of DGF was associated with lower graft survival (log‐rank test P = 0.034), though duration of DGF was not (P = 0.723). However, multivariable Cox regression analysis found that only acute rejection was independently associated with lower graft survival [HR (95% CI) 4.302 (1.617–11.450); P = 0.003], whereas the presence of DGF and DGF duration were not. In controlled DCD kidney transplantation, DGF duration itself may not be independently associated with graft survival; rather, it may be that acute rejection associated with prolonged DGF is the poor prognostic factor.     

Urinary metabolites predict prolonged duration of delayed graft function in DCD kidney transplant recipients

Extending kidney donor criteria, including donation after circulatory death (DCD), has resulted in increased rates of delayed graft function (DGF) and primary nonfunction. Here, we used Nuclear Magnetic Resonance (NMR) spectroscopy to analyze the urinary metabolome of DCD transplant recipients at multiple time points (days 10, 42, 180, and 360 after transplantation). The aim was to identify markers that predict prolonged duration of functional DGF (fDGF). Forty‐seven metabolites were quantified and their levels were evaluated in relation to fDGF. Samples obtained at day 10 had a different profile than samples obtained at the other time points. Furthermore, at day 10 there was a statistically significant increase in eight metabolites and a decrease in six metabolites in the group with fDGF (N = 53) vis‐à‐vis the group without fDGF (N = 22). In those with prolonged fDGF (≥21 days) (N = 17) urine lactate was significantly higher and pyroglutamate lower than in those with limited fDGF (<21 days) (N = 36). In order to further distinguish prolonged fDGF from limited fDGF, the ratios of all metabolites were analyzed. In a logistic regression analysis, the sum of branched‐chain amino acids (BCAAs) over pyroglutamate and lactate over fumarate, predicted prolonged fDGF with an AUC of 0.85. In conclusion, kidney transplant recipients with fDGF can be identified based on their altered urinary metabolome. Furthermore, two ratios of urinary metabolites, lactate/fumarate and BCAAs/pyroglutamate, adequately predict prolonged duration of fDGF.     

A novel genomic model for predicting the likelihood of delayed graft function in DCD kidney transplantation

BackgroundThe high incidence of delayed graft function (DGF) following kidney transplantation with donation after cardiac death allografts (DCD-KT) poses great challenges to transplant clinicians. This study aimed to explore the DGF-related biomarkers and establish a genomic model for DGF prediction specific to DCD KT.MethodsBy data mining a public dataset ({"type":"entrez-geo","attrs":{"text":"GSE43974","term_id":"43974"}}GSE43974), the key DGF-related genes in DCD kidney biopsies taken after short-time reperfusion (45–60 min) were identified by differential expression analysis and a LASSO-penalized logistic regression model. Their coefficients for modeling were calculated by multivariate logistic regression. Receiver operating characteristic curves and a nomogram were generated to evaluate its predictive ability for DGF occurrence. Gene set enrichment analysis (GSEA) was performed to explore biological pathways underlying DGF in DCD KT.ResultsFive key DGF-related genes (CHST3, GOLPH3, ZBED5, AKR1C4, and ERRFI1) were first identified, all of which displayed good discrimination for DGF occurrence after DCD KT (all P<0.05). A five-mRNA-based risk score was further established and showed excellent predictive ability (AUC =0.9708, P<0.0001), which was obviously higher than that of the five genes alone. Eight DGF-related biological pathways in DCD kidneys, such as “arachidonic acid metabolism”, “lysosome”, “proximal tubule bicarbonate reclamation”, “glutathione metabolism”, were identified by GSEA (all P<0.05). Moreover, a convenient and visual nomogram based on the genomic risk score was also constructed and displayed high accuracy for DGF prediction specific to DCD KT.ConclusionsThe novel genomic model may effectively predict the likelihood of DGF immediately after DCD KT or even prior to transplantation in the context of normothermic machine perfusion in the future.     

Kidney transplantation from donation after cardiac death donors: lack of impact of delayed graft function on post‐transplant outcomes

Singh RP, Farney AC, Rogers J, Zuckerman J, Reeves‐Daniel A, Hartmann E, Iskandar S, Adams P, Stratta RJ. Kidney transplantation from donation after cardiac death donors: lack of impact of delayed graft function on post‐transplant outcomes.
Clin Transplant 2011: 25: 255–264. © 2010 John Wiley & Sons A/S. Abstract: Introduction: Delayed graft function (DGF) is more common in recipients of kidney transplants from donation after cardiac death (DCD) donors compared to donation after brain death (DBD) donors. Methods: Single‐center retrospective study to evaluate the impact of DGF on controlled (Maastricht category III) DCD donor kidney transplant outcomes. Results: From 10/01 to 6/08, 578 adult deceased donor kidney transplants were performed including 70 (12%) from DCD and 508 (88%) from DBD donors. Mean follow‐up was 36 months. DCD donor kidney transplants had significantly greater rates of DGF (57% DCD vs. 21% DBD, p < 0.0001)) and acute rejection (29% DCD vs. 16% DBD, p = 0.018) compared to DBD donor kidney transplants, but patient and graft survival rates were similar. DBD donor kidney transplants with DGF (n = 109) had significantly greater rates of death‐censored graft loss (12.5% DCD vs. 31% DBD), primary non‐function (0 DCD vs. 10% DBD) and higher 2 year mean serum creatinine levels (1.4 DCD vs. 2.7 mg/dL DBD) compared to DCD donor kidney transplants with DGF (n = 40, all p < 0.04). On univariate analysis, the presence of acute rejection and older donor age were the only significant risk factors for death‐censored graft loss in DCD donor kidney transplants, whereas DGF was not a risk factor. Conclusion: Despite higher rates of DGF and acute rejection in DCD donor kidney transplants, subsequent outcomes in DCD donor kidney transplants with DGF are better than in DBD donor kidney transplants experiencing DGF, and similar to outcomes in DCD donor kidney transplants without DGF.     

Risk factors for delayed kidney function and impact of delayed function on patient and graft survival in adult graft recipients

The influence of delayed kidney graft function on allograft outcome is described controversially in the literature. The aim of the study was to evaluate possible risk factors for delayed graft function (DGF) and investigate the impact of DGF on short- and long-term renal allograft function. Two groups were formed: the first one consisted of patients who gained immediate graft function (IGF) (n = 64) after transplantation and the second group included patients with DGF (n = 31; with at least one dialysis needed in first week after transplantation). The DGF group had a statistically significant longer duration on dialyses prior to transplantation (DGF 54 vs. IGF 33 months; p < 0.05), on average more frequently a re-transplantation (DGF 1.7 vs. IGF 1.3; p < 0.01), a longer re-anastomosis time (DGF 52.9 vs. 44.2 min; p < 0.01), a lower systolic (DGF 136 +/-24 mmHg vs. IGF 158 +/- 25; p < 0.001) and diastolic blood pressure (DGF 78 +/- 14 vs. IGF 89 +/- 16 mmHg; p < 0.01) at admission to the hospital and a higher serum (S)-creatinine at discharge (DGF 2.5 +/- 1.6 vs. IGF 1.6 +/- 0.4 mg/dL; p < 0.01). Prior to transplantation the DGF group had more often advanced vascular diseases (DGF 29.0 vs. IGF 12.5%; p < 0.01) and these patients incurred more frequently new ones during the next 3 yr after transplantation (DGF 22.6 vs. IGF 6.3%; p < 0.001). After 3 yr the graft survival tended to be lower in the DGF group (DGF 74.2 vs. IGF 84.4%; NS), but this difference was not statistically significant.     

Impact of donor age on long‐term outcomes after delayed graft function: 10‐year follow‐up

Delayed graft function (DGF) has a negative impact on graft survival in donation after brain death (DBD) but not for donation after cardiac death (DCD) kidneys. However, older donor age is associated with graft loss in DCD transplants. We sought to examine the interaction between donor age and DGF in DBD kidneys. This is a single‐center, retrospective review of 657 consecutive DBD recipients transplanted between 1990 and 2005. We stratified the cohort by decades of donor age and studied the association between DGF and graft failure using Cox models. The risk of graft loss associated with DGF was not significantly increased for donor age below 60 years (adjusted hazard ratio [aHR] 1.12, 1.51, and 0.90, respectively, for age <40, 41–50 and 51–60 years) but significantly increased after 60 years (aHR 2.67; P = 0.019). Analysis of death‐censored graft failure yielded similar results for donor age below 60 years and showed a substantially increased risk with donors above 60 years (aHR 6.98, P = 0.002). This analysis reveals an unexpectedly high impact of older donor age on the association between DGF and renal transplant outcomes. Further research is needed to determine the best use of kidneys from donors above 60 years old, where DGF is expected.     

Financial impact of delayed graft function in kidney transplantation

Increased utilization of suboptimal organs in response to organ shortage has resulted in increased incidence of delayed graft function (DGF) after transplantation. Although presumed increased costs associated with DGF are a deterrent to the utilization of these organs, the financial burden of DGF has not been established. We used the Premier Healthcare Database to conduct a retrospective analysis of healthcare resource utilization and costs in kidney transplant patients (n = 12 097) between 1/1/2014 and 12/31/2018. We compared cost and hospital resource utilization for transplants in high-volume (n = 8715) vs low-volume hospitals (n = 3382), DGF (n = 3087) vs non-DGF (n = 9010), and recipients receiving 1 dialysis (n = 1485) vs multiple dialysis (n = 1602). High-volume hospitals costs were lower than low-volume hospitals ($103 946 vs $123 571, P < .0001). DGF was associated with approximately $18 000 (10%) increase in mean costs ($130 492 vs $112 598, P < .0001), 6 additional days of hospitalization (14.7 vs 8.7, P < .0001), and 2 additional ICU days (4.3 vs 2.1, P < .0001). Multiple dialysis sessions were associated with an additional $10 000 compared to those with only 1. In conclusion, DGF is associated with increased costs and length of stay for index kidney transplant hospitalizations and payment schemes taking this into account may reduce clinicians’ reluctance to utilize less-than-ideal kidneys.     

移植肾功能延迟恢复的临床诊治体会

目的．探讨肾移植术后移植肾功能延迟恢复（DGF）的病因及治疗方法。方法分析本组发生的43例肾移植术后DGF患者的临床资料，主要原因：急性排斥（AR）17例（39．5％），急性肾小管坏死（ATN）16例（37．2％），输尿管梗阻4例（9．3％），免疫抑制剂肾毒性4例（9．3％），动脉吻合口狭窄2例（4．6％）。经血液透析治疗16例，ATG／ALG或OKT3治疗12例，外科手术6例。结果36例肾移植术后8—113d（平均23．8d）肾功能恢复正常，2例肌酐在176—300μmol／L之间，4例恢复血透，1例死于肺部感染。结论AR和ATN是引起肾移植术后DGF的主要因素，术前严格配型、合理筛选受者及保证供肾质量等是成功的关键。     

The relative influence of delayed graft function and acute rejection on renal transplant survival

Three hundred and eight cadaveric renal transplants were analysed to establish the effects of acute rejection in the first 90 days and delayed graft function (DGF) on graft outcome. There were 120 patients (39%) with no DGF and no rejection (group 1), 101 patients (33%) with rejection but no DGF (group 2), 41 patients (13%) with DGF but no rejection (group 3) and 46 patients (15%) with both rejection and DGF (group 4). The actuarial 4-year graft survival rates for groups 1,2,3 and 40.4%, respectively. The acute rejection rate was 101/221 (46%) in patients with initial graft function compared with 46/87 (53%) for those with DGF (²=1.02, P=0.31). Cox stepwise logistic regression analysis demonstrated that DGF was a more powerful predictive factor for poor graft survival (P=0.001) than acute rejection occurring in the first 90 days post-transplant (P=0.034). Further efforts at improving graft outcome should concentrate on reducing the incidence of DGF.     

Influence of CIT-induced DGF on kidney transplant outcomes

Increased cold ischemia time (CIT) predisposes to delayed graft function (DGF). DGF is considered a risk factor for graft failure after kidney transplantation, but DGF has multiple etiologies. To analyze the risk of CIT-induced DGF on graft survival, we evaluated paired deceased-donor kidneys (derived from the same donor transplanted to different recipients) in which one donor resulted in DGF and the other did not, using national Scientific Registry of Transplant Recipients data between 2000 and 2009. Of 54 565 kidney donors, 15 833 were excluded for mate kidney non-transplantation, 27 340 because both or neither kidney developed DGF and 2310 for same/unknown CIT. The remaining 9082 donors (18 164 recipients) were analyzed. The adjusted odds (aOR) of DGF were significantly higher when CIT was longer by ≥ 1 h (aOR 1.81, 95% CI 1.7-2.0), ≥ 5 h (aOR 2.5, 95% CI 2.3-2.9), ≥ 10 h (aOR 3.3, 95% CI 2.7-2.9) and ≥ 15 h (aOR 4.4, 95% CI 3.4-5.8) compared to shorter CIT transplants. In the multivariable models adjusted for recipient characteristics, graft survival between paired donor transplants, with and without DGF, were similar. These results suggest that DGF, specifically induced by prolonged CIT, has limited bearing on long-term outcomes, which may have important implications for kidney utilization.     

Peri‐operative hyperglycemia is associated with delayed graft function in deceased donor renal transplantation

Increasing evidence indicates that recipient diabetes is a risk factor for delayed graft function (DGF) after renal transplant and that peri‐operative hyperglycemia increases ischemia–reperfusion injury. To evaluate whether peri‐operative hyperglycemia as measured in the post‐anesthesia care unit (PACU) after transplant is a risk factor for DGF, we retrospectively reviewed 976 adult recipients of deceased donor renal transplants between January 1, 1997 and December 1, 2004. Logistic regression was used to evaluate risk factors for DGF. In our final multivariate model, recipient blood glucose level in the PACU (odds ratio [OR] 1.10 per 25 unit increase, 95% confidence interval (CI) 1.14–2.46, p = 0.03) was a statistically significant predictor of DGF along with donor age (OR 1.02, 95% CI 1.01–1.03, p < 0.01), cold ischemia time (OR 1.04, 95% CI 1.02–1.07, p < 0.01), recipient male gender (OR 1.68, 95% CI 1.14–2.68, p = 0.01), and a panel‐reactive antibody >30% (OR 1.92, 95% CI 1.20–3.05, p = 0.01). We conclude that recipient blood glucose measured in the PACU is associated with DGF and begs the question of whether improved peri‐operative glucose control will decrease the incidence of DGF.     

Early post‐transplant conversion from tacrolimus to belatacept for prolonged delayed graft function improves renal function in kidney transplant recipients

Prolonged delayed graft function (DGF) in kidney transplant recipients imparts a risk of poor allograft function; tacrolimus may be detrimental in this setting. We conducted a retrospective single center analysis of the first 20 patients converted to belatacept for prolonged DGF as part of a clinical protocol as a novel treatment strategy to treat prolonged DGF. Prior to conversion, patients underwent an allograft biopsy to rule out rejection and confirm tubular injury. The primary outcome was the estimated glomerular filtration rate (eGFR) at 12 months post‐transplant; secondary outcome was the change in eGFR 30 days post‐belatacept conversion. At 1 year post‐transplant, the mean eGFR was 54.2 (SD 19.2) mL/min/1.73 m². The mean eGFR on the day of belatacept conversion was 16 (SD 12.7) mL/min/1.73 m² and rose to 43.1 (SD 15.8) mL/min/1.73 m² 30 days post‐conversion (P<.0001). The acute rejection rate was 20% with 100% patient survival at 12 months post‐transplant. There was one graft loss in the setting of an invasive Aspergillus infection that resulted in withdrawal of immunosuppression and transplant nephrectomy. Belatacept conversion for prolonged DGF is a novel treatment strategy that resulted in an improvement in eGFR. Additional follow‐up is warranted to confirm the long‐term benefits of this strategy.     

Transplanting kidneys from donation after cardiac death donors with acute kidney injury

Donation after cardiac death (DCD) and acute kidney injury (AKI) donors have historically been considered independent risk factors for delayed graft function (DGF), allograft failure, and inferior outcomes. With growing experience, updated analyses have shown good outcomes. There continues to be limited data, however, on outcomes specific to DCD donors who have AKI. Primary outcomes for this study were post–kidney transplant patient and allograft survival comparing two donor groups: DCD AKIN stage 2‐3 and DBD AKIN stage 2‐3. In comparing these groups, there were no short‐ or long‐term differences in patient (hazard ratio [HR] 1.07, 95% confidence interval [CI] 0.54‐1.93, P = .83) or allograft survival (HR 1.47, 95% CI 0.64‐2.97, P = .32). In multivariate models, the DCD/DBD status had no significant impact on the estimated GFR (eGFR) at 1 (P = .38), 2 (P = .60), and 3 years (P = .52). DGF (57.9% vs 67.9%, P = .09), rejection (12.1% vs 13.9%, P = .12), and progression of interstitial fibrosis/tubular atrophy (IFTA) on protocol biopsy (P = .16) were similar between the two groups. With careful selection, good outcomes can be achieved utilizing severe AKI DCD kidneys. Historic concerns regarding primary nonfunction, DGF resulting in interstitial fibrosis and rejection, and inferior outcomes were not observed. Given the ongoing organ shortage, increased effort should be undertaken to further utilize these donors.     

Kidney donation after circulatory death in a country with a high number of brain dead donors: 10-year experience in Belgium

Worldwide shortage of standard brain dead donors (DBD) has revived the use of kidneys donated after circulatory death (DCD). We reviewed the Belgian DCD kidney transplant (KT) experience since its reintroduction in 2000. Risk factors for delayed graft function (DGF) were identified using multivariate analysis. Five-year patient/graft survival was assessed using Kaplan-Meier curves. The evolution of the kidney donor type and the impact of DCDs on the total KT activity in Belgium were compared with the Netherlands. Between 2000 and 2009, 287 DCD KT were performed. Primary nonfunction occurred in 1% and DGF in 31%. Five-year patient and death-censored graft survival were 93% and 95%, respectively. In multivariate analysis, cold storage (versus machine perfusion), cold ischemic time, and histidine-tryptophan-ketoglutarate solution were independent risk factors for the development of DGF. Despite an increased number of DCD donations and transplantations, the total number of deceased KT did not increase significantly. This could suggest a shift from DBDs to DCDs. To increase KT activity, Belgium should further expand controlled DCD programs while simultaneously improve the identification of all potential DBDs and avoid their referral for donation as DCDs before brain death occurs. Furthermore, living donation remains underused.     

Impact of cold ischemia time on renal allograft outcome using kidneys from young donors

Prolonged cold ischemia time (CIT) is associated with delayed graft function and worse kidney transplant (KT) outcome, but the effect of CIT on long‐term allograft survival in KT from younger donors has not been well established. We investigated the predictive value of CIT exposure on long‐term death‐censored graft loss in 829 KT recipients from younger donors (<50 years) that were performed in our center between 1991 and 2005. Overall death‐censored graft failure rate was significantly higher in CIT≥19 h group versus CIT<19 h group (26 vs. 16.5%; P = 0.002). Significant differences were also observed when patients with primary nonfunctioning graft were excluded (21 vs. 14%; P = 0.020) and in patients who received tacrolimus plus mycophenolate mofetil (12 vs. 4%; P = 0.05). By multivariate Cox analysis, CIT was found to be independently associated with death‐censored graft loss with a 20% increase for every 5 h of CIT [relative risk (RR) 1.04; 95% Confidence Interval (CI): 1.01–1.1; P = 0.021]. Likewise, graft loss risk significantly increased in CIT≥19 h group versus CIT<19 h group (RR 1.5; 95%CI: 1.1–2.1; P = 0.023). Prolonged CIT is an independent predictor of graft survival in KT from younger donors. Efforts at minimizing CIT (<19 h) should improve transplant outcome significantly in this population.