Delayed Graft Function in Kidney Transplants: Time Evolution, Role of Acute Rejection, Risk Factors, and Impact on Patient and Graft Outcome

Kidney Tissue Proteome Profiles in Short Versus Long Duration of Delayed Graft Function - A Pilot Study in Donation After Circulatory Death Donors

Introduction

Delayed graft function (DGF) is often defined as the need for dialysis treatment in the first week after a kidney transplantation. This definition, though readily applicable, is generic and unable to distinguish between "types" of DGF or time needed to recover function that may also significantly affect longer-term outcomes. We aimed to profile biological pathways in donation after circulatory death (DCD) kidney donors that correlate with DGF and different DGF durations.

Methods

A total of N = 30 DCD kidney biopsies were selected from the UK Quality in Organ Donation (QUOD) biobank and stratified according to DGF duration (immediate function, IF n = 10; "short-DGF" (1-6 days), SDGF n = 10; "long-DGF" (7-22 days), LDGF n = 10). Samples were matched for donor and recipient demographics and analyzed by label-free quantitative (LFQ) proteomics, yielding identification of N = 3378 proteins.

Results

Ingenuity pathway analysis (IPA) on differentially abundant proteins showed that SDGF kidneys presented upregulation of stress response pathways, whereas LDGF presented impaired response to stress, compared to IF. LDGF showed extensive metabolic deficits compared to IF and SDGF.

Conclusion

DCD kidneys requiring dialysis only in the first week posttransplant present acute cellular injury at donation, alongside repair pathways upregulation. In contrast, DCD kidneys requiring prolonged dialysis beyond 7 days present minimal metabolic and antioxidant responses, suggesting that current DGF definitions might not be adequate in distinguishing different patterns of injury in donor kidneys contributing to DGF.

Review of prognostic factors for kidney transplant survival

Transplantation is the most effective treatment for end-stage chronic kidney disease, as this procedure prolongs and improves the patient's quality of life. One of the key problems is the risk of graft rejection. The purpose of this research was to identify and analyse prognostic factors that will prevent rejection. In particular, the prognostic factors grouped by methods of synthesis, generalisation and statistical processing with calculation and graphical representation of hazard ratio and correlation coefficient were grouped, namely: age of donor and recipient, time of cold kidney ischaemia, duration of preoperative dialysis, body mass index, presence of concomitant diseases (diabetes mellitus, hypertension), primary causes causing transplantation. Several molecular genetic and biochemical prognostic markers (transcription factors, immunocompetent cell signalling and receptors, cytostatin C, creatinine, citrate, lactate, etc.) are annotated. It has been demonstrated that creatinine reduction rate determines the risk of rejection, displaying the dynamics of cystatin C and creatinine changes in the postoperative period. Young recipients who underwent prolonged preoperative dialysis were identified as having the highest risk of rejection. Diabetes and hypertension bear a non-critical but commensurately equal risk of rejection. The survival rate of the graft is better when transplanted from a living donor than from a deceased donor. A correlation between cold ischaemia time, body mass index and the probability of graft failure has been proven, namely, the greater the donor and recipient body mass index and the longer the cold ischaemia time, the lower the chance of successful long-term organ acclimation. The data obtained can be used as prognostic factors for graft accommodation at different intervals after surgery.

Kidney Transplant Outcomes after Prolonged Delayed Graft Function

Background: The protracted recovery of renal function may be an actionable marker of post-transplant adverse events, but a paucity of data are available to determine if the duration of graft recovery serves to stratify risk. Materials and Methods: Single-center data of adult-isolated deceased-donor kidney transplant (KTX) recipients between 1 July 2015 and 31 December 2018 were stratified by delayed graft function (DGF) duration, defined as time to serum creatinine < 3.0 mg/dL. Results: Of 355 kidney transplants, the time to creatinine < 3.0 mg/dL was 0−3 days among 96 cases (DGF ≤ 3), 4−10 days among 85 cases (DGF4-10), 11−20 days among 93 cases (DGF11-20), and ≥21 days for 81 cases (DGF ≥ 21). DGF ≥ 21 recipients were significantly more likely to be male, non-sensitized, and receive kidneys from donors that were older, with donation after circulatory death, non-mandatory share, hypertensive, higher KDPI, higher terminal creatinine, and longer cold and warm ischemia time. On multivariate analysis, DGF ≥ 21 was associated with a 5.73-fold increased odds of 12-month eGFR < 40 mL/min compared to DGF ≤ 3. Lesser degrees of DGF had similar outcomes. Conclusions: Prolonged DGF lasting over 20 days signifies a substantially higher risk for reduced eGFR at 1 year compared to lesser degrees of DGF, thus serving as a threshold indicator of increased risk.

Predictors of Delayed Graft Function in Renal Transplantation

PURPOSE

This study aimed to analyze our data on delayed graft function (DGF) and to identify associated factors.

METHODS

This is a retrospective case-control study of all patients transplanted in our center over a period of 11 years (January 1, 2003, to December 31, 2014) comparing patients with immediate graft function (n = 332) to those with DGF (n = 165). DGF was defined as the need for hemodialysis within the first 7 days after transplantation. Donor and recipient characteristics as well as procedural factors were compared by univariate and multivariate logistic regression analyses.

RESULTS

Overall, 33% of patients had DGF. The rate of DGF declined from 2003 to 2011. In cases with DGF, donors and recipients were significantly older (p = 0.004 and p = 0.005, respectively), had longer cold ischemia times (p = 0.039), more revision surgeries (p < 0.001), and more HLA mismatches (p = 0.001), especially in the DR locus (p = 0.002). Neither donor nor recipient gender, waiting time, nor CMV status had any influence. In multivariable analysis, significant risk factors were ischemia time and mismatches at the HLA-DR loci.

CONCLUSIONS

DGF is a common complication in renal transplantation which occurred in 33% of our cases. Important factors identified were donor and recipient age, ischemia time, HLA mismatching, and revision surgery.

Intraoperative fluid management and kidney transplantation outcomes: A retrospective cohort study

BACKGROUND

Patients undergoing kidney transplantation traditionally receive liberal amounts of fluid during surgery. However, excessive fluids can lead to fluid overload and ileus. In this retrospective cohort study, we compared the effect of restrictive versus liberal fluid therapy on kidney transplantation outcomes.

METHODS

Patients who underwent deceased-donor kidney transplantation at Mayo Clinic from January 2014 to March 2019 were included. Those who received <3 L of intravenous fluids intraoperatively were categorized as "restrictive;" those who received ≥3 L were categorized as "liberal." The primary outcome was incidence of delayed graft function (DGF). Secondary outcomes included length of stay, readmission within 30 days, time to return of bowel function, and incidence of postoperative complications.

RESULTS

Of the 1171 patients included, 557 were in the restrictive group and 614 in the liberal group. The mean (SD) fluid intake was 2.17 (.54) L in the restrictive group and 3.67 (.68) L in the liberal group (P<.001). There was no difference in DGF (relative risk, 1.03; P = .56), length of stay (P = .34), readmission (P = .80), return of bowel function (P = .71), or other postoperative complications.

CONCLUSIONS

Intraoperative restrictive fluid therapy during kidney transplantation was not associated with DGF or worse outcomes when compared with liberal fluid therapy.

Risk factors and outcomes of prolonged recovery from delayed graft function after deceased kidney transplantation

Objective

We aimed to evaluate the effect of prolonged recovery from DGF on outcomes, using a new definition of DGF recovery time, among deceased donor kidney transplant recipients with DGF, and to examine the risk factors for prolonged recovery.

Methods

From 2007 to 2016, 91 deceased donor kidney transplant recipients with DGF were retrospectively analyzed. DGF recovery time was defined as the time from transplantation to achieve a stable estimated glomerular filtration rate (eGFR). Recipients with a DGF recovery time greater than or equal to the median were assigned to the prolonged recovery group, while the others were assigned to the rapid recovery group.

Result

The median DGF recovery time was 27 days. Donor terminal eGFR was significantly lower in the prolonged recovery group (n = 46) compared with the rapid recovery group (n = 45) (median 24.9 vs. 65.4 ml/min/1.73m², p = 0.004). The eGFR at 1 year post-transplant in the prolonged recovery group was significantly lower than that in the rapid recovery group (50.6 ± 20.0 vs. 63.5 ± 21.4 ml/min/1.73m², p = 0.005). The risk of adverse outcomes (acute rejection, pneumonia, graft failure, and death) was significantly greater in the prolonged recovery group (hazard ratio 2.604, 95% confidence interval 1.102–6.150, p = 0.029) compared with the rapid recovery group.

Conclusion

Decreased donor terminal eGFR is a risk factor for prolonged recovery from DGF after deceased kidney transplantation. Prolonged DGF recovery time is associated with reduced graft function at 1-year post-transplant, and poor transplant outcome.

Acute Kidney Injury (AKI) before and after Kidney Transplantation: Causes, Medical Approach, and Implications for the Long-Term Outcomes

Acute kidney injury (AKI) is a common finding in kidney donors and recipients. AKI in kidney donor, which increases the risk of delayed graft function (DGF), may not by itself jeopardize the short- and long-term outcome of transplantation. However, some forms of AKI may induce graft rejection, fibrosis, and eventually graft dysfunction. Therefore, various strategies have been proposed to identify conditions at highest risk of AKI-induced DGF, that can be treated by targeting the donor, the recipient, or even the graft itself with the use of perfusion machines. AKI that occurs early post-transplant after a period of initial recovery of graft function may reflect serious and often occult systemic complications that may require prompt intervention to prevent graft loss. AKI that develops long after transplantation is often related to nephrotoxic drug reactions. In symptomatic patients, AKI is usually associated with various systemic medical complications and could represent a risk of mortality. Electronic systems have been developed to alert transplant physicians that AKI has occurred in a transplant recipient during long-term outpatient follow-up. Herein, we will review most recent understandings of pathophysiology, diagnosis, therapeutic approach, and short- and long-term consequences of AKI occurring in both the donor and in the kidney transplant recipient.

A prediction model of delayed graft function in deceased donor for renal transplant: a multi-center study from China

Background

Kidneys obtained from deceased donors increase the incidence of delayed graft function (DGF) after renal transplantation. Here we investigated the influence of the risk factors of donors with DGF, and developed a donor risk scoring system for DGF prediction.

Methods

This retrospective study was conducted in 1807 deceased kidney donors and 3599 recipients who received donor kidneys via transplants in 29 centers in China. We quantified DGF associations with donor clinical characteristics. A donor risk scoring system was developed and validated using an independent sample set.

Results

The incidence of DGF from donors was 19.0%. Six of the donor characteristics analyzed, i.e., age, cause of death, history of hypertension, terminal serum creatinine, persistence of hypotension, and cardiopulmonary resuscitation (CPR) time were risk factors for DGF. A 49-point scoring system of donor risk was established for DGF prediction and exhibited a superior degree of discrimination. External validation of DGF prediction revealed area under the receiver-operating characteristic (AUC) curves of 0.7552.

Conclusions

Our study determined the deceased donor risk factors related to DGF after renal transplantation pertinent to the Chinese cohort. The scoring system developed here had superior diagnostic significance and consistency and can be used by clinicians to make evidence-based decisions on the quality of kidneys from deceased donors and guide renal transplantation therapy.

Evaluation of the effect of high dose intravenous vitamin C on delayed allograft function in deceased donor kidney transplantation: a preliminary report

Background

Delayed graft function (DGF) can affect short- and long-term allograft outcomes in kidney transplant recipients. One of the pathophysiological pathways in the occurrence of DGF is ischemia-reperfusion injury (IRI). High dose intravenous vitamin C has proven efficacy in decreasing IRI consequences. Accordingly, we designed this study to assess the effect of high dose intravenous vitamin C on the incidence and duration of DGF.

Methods

This is a pilot, single-center, double-blinded, randomized, placebo-controlled trial. In the treatment group, kidney transplant recipients received vitamin C infusion at the dose of 70 mg/kg diluted in 0.45% saline, and in another study arm, only the diluent solution was administered. Data regarding allograft function and other clinical information was recorded.

Results

This preliminary study on 19 patients (9 cases in the vitamin C and 10 cases in the placebo group) showed that after administration of single, high dose vitamin C the incidence of DGF was not significantly different between the groups, but the duration of DGF was substantially shorter in the vitamin C group than the placebo group (7.33 ± 5.68 versus 19.66 ± 0.57 days; P = 0.02). Acute rejection episodes were more seen in the vitamin C group than in the placebo group. Although this data was not statistically significant (P = 0.37), it led to the termination of the study.

Conclusion

A high dose of intravenous vitamin C before allograft implantation was effective in decreasing DGF duration but not DGF incidence.

Trial registration

The trial was registered in the Iranian registry of clinical trials encoded IRCT20100111003043N13 on June 24, 2019.

Intravenous Fluid Management Practices in Kidney Transplant Patients: A Multicenter Observational Cohort Pilot Study

BACKGROUND

Limited evidence exists with regard to best practices in fluid management during kidney transplantation, which may directly affect the incidence of DGF. The authors of this study embarked on a collaborative observational multicenter pilot study to evaluate fluid administration practices in different transplant centers, with a focus on the relationship between total administered crystalloid volume and its association with DGF.

METHODS

Twenty consecutive kidney transplant patients were included from 9 academic medical centers in the United States. One hundred eighty patients were included in the final cohort and variables were compared between patients with and without DGF. Administered crystalloid volume was the primary variable of interest; however, additional patient and surgical variables were compared between patients with and without DGF. Variation in crystalloid administration was explored between centers by comparing median administered crystalloid volumes per kilogram of body weight. Also, unadjusted and adjusted logistic regression analyses were performed to determine which variables were independently associated with DGF.

RESULTS

Multivariable regression modeling demonstrated that cold ischemic time and ephedrine use during surgery were independently associated with DGF. There was no independent association between administered crystalloid volume and DGF.

CONCLUSION

In this study of patients having kidney transplantation, we did not find an independent association between administered crystalloid volume and DGF, although there was significant variability in crystalloid administration between centers. Our data suggest that DGF was driven mainly by surgical factors such as cold ischemic time. Ephedrine was also independently associated with DGF, which should be explored in future studies.

Predicting urine output after kidney transplantation: development and internal validation of a nomogram for clinical use

Purpose:

To analyze pre-transplantation and early postoperative factors affecting post-transplantation urine output and develop a predictive nomogram.

Patients and Methods:

Retrospective analysis of non-preemptive first transplanted adult patients between 2001-2016. The outcomes were hourly diuresis in mL/Kg in the 1^st (UO₁) and 8^th (UO₈) postoperative days (POD). Predictors for both UO₁ and UO₈ were cold ischemia time (CIT), patient and donor age and sex, HLA I and II compatibility, pre-transplantation duration of renal replacement therapy (RRT), cause of ESRD (ESRD) and immunosuppressive regimen. UO₈ predictors also included UO₁, 1^st/0^th POD plasma creatinine concentration ratio (Cr_1/0), and occurrence of acute cellular rejection (AR). Multivariable linear regression was employed to produce nomograms for UO₁ and UO₈.

Results:

Four hundred and seventy-three patients were included, mostly deceased donor kidneys’ recipients (361, 70.4%). CIT inversely correlated with UO₁ and UO₈ (Spearman's p=-0.43 and −0.37). CR_1/0 inversely correlated with UO₈ (p=-0.47). On multivariable analysis UO₁ was mainly influenced by CIT, with additional influences of donor age and sex, HLA II matching and ESRD. UO₁ was the strongest predictor of UO₈, with significant influences of AR and ESRD.

Conclusions:

The predominant influence of CIT on UO₁ rapidly wanes and is replaced by indicators of functional recovery (mainly UO₁) and allograft's immunologic acceptance (AR absence). Mean absolute errors for nomograms were 0.08 mL/Kg h (UO₁) and 0.05 mL/Kg h (UO₈).

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.

Association of Dialysis Duration With Outcomes After Kidney Transplantation in the Setting of Long Cold Ischemia Time

Background

There is no mechanism that matches hard-to-place kidneys with the most appropriate candidate. Thus, unwanted kidney offers are typically to recipients with long renal replacement time (vintage) which is a strong risk factor for mortality and graft failure, and in combination with prolonged cold ischemia time (CIT), may promote interactive effects on outcomes.

Methods

Consecutive adult isolated kidney transplants between October 2015 and December 2017 were stratified by vintage younger than 1 year and CIT longer than 30 hours.

Results

Long (n = 169) relative to short (n = 93) vintage recipients were significantly more likely to be younger (32.2 years vs 56.9 years, P = 0.02), black race (40.8% vs 18.3%, P = 0.02), have higher estimated posttransplant survival (52.6 vs 42.0, P = 0.04), and have a comorbid condition (45.6% vs 30.1%, P = 0.02); they were less likely to receive a donation after circulatory death kidney (27.8% vs 39.8%, P = 0.05). Long vintage was significantly associated with length of stay longer than 4 days (45.5% vs 30.1%, P = 0.02), and 30-day readmission (37.3% vs 22.6%, P = 0.02) but not additional operations (17.8% vs 15.1%, P = 0.58), short-term patient mortality (3.0% vs 2.2%, P = 0.70), or overall graft survival (P = 0.23). On multivariate logistic regression, long vintage remained an independent risk factor for 30-day readmission (adjusted odds ratio, 1.92; 95% confidence interval, 1.06-3.47); however, there was no interaction of vintage and CIT for this outcome (P = 0.84).

Conclusions

Readmission is significantly associated with pretransplant dialysis duration; however, CIT is not a modifying factor for this outcome.

Perioperative Goal-Directed Therapy during Kidney Transplantation: An Impact Evaluation on the Major Postoperative Complications

Background: Kidney transplantation is considered the first-choice therapy in end-stage renal disease (ESRD) patients. Despite recent improvements in terms of outcomes and graft survival in recipients, postoperative complications still concern the health-care providers involved in the management of those patients. Particularly challenging are cardiovascular complications. Perioperative goal-directed fluid-therapy (PGDT) and hemodynamic optimization are widely used in high-risk surgical patients and are associated with a significant reduction in postoperative complication rates and length of stay (LOS). The aim of this work is to compare the effects of perioperative goal-directed therapy (PGDT) with conventional fluid therapy (CFT) and to determine whether there are any differences in major postoperative complications rates and delayed graft function (DGF) outcomes. Methods: Prospective study with historical controls. Two groups, a PGDT and a CFT group, were used: The stroke volume (SV) optimization protocol was applied for the PGDT group throughout the procedure. Conventional fluid therapy with fluids titration at a central venous pressure (CVP) of 8–12 mmHg and mean arterial pressure (MAP) >80 mmHg was applied to the control group. Postoperative data collection including vital signs, weight, urinary output, serum creatinine, blood urea nitrogen, serum potassium, and assessment of volemic status and the signs and symptoms of major postoperative complications occurred at 24 h, 72 h, 7 days, and 30 days after transplantation. Results: Among the 66 patients enrolled (33 for each group) similar physical characteristics were proved. Good functional recovery was evident in 92% of the CFT group, 98% of the PGDT group, and 94% of total patients. The statistical analysis showed a difference in postoperative complications as follows: Significant reduction of cardiovascular complications and DGF episodes (p < 0.05), and surgical complications (p < 0.01). There were no significant differences in pulmonary or other complications. Conclusions: PGDT and SV optimization effectively influenced the rate of major postoperative complications, reducing the overall morbidity and thus the mortality in patients receiving kidney transplantation.

The future of marginal kidney repair in the context of normothermic machine perfusion

Normothermic machine perfusion (NMP) is a technique that utilizes extracorporeal membrane oxygenation to recondition and repair kidneys at near body temperature prior to transplantation. The application of this new technology has been fueled by a significant increase in the use of the kidneys that were donated after cardiac death, which are more susceptible to ischemic injury. Preliminary results indicate that NMP itself may be able to repair marginal organs prior to transplantation. In addition, NMP serves as a platform for delivery of therapeutics. The isolated setting of NMP obviates problems of targeting a particular therapy to an intended organ and has the potential to reduce the harmful effects of systemic drug delivery. There are a number of emerging therapies that have shown promise in this platform. Nutrients, therapeutic gases, mesenchymal stromal cells, gene therapies, and nanoparticles, a newly explored modality, have been successfully delivered during NMP. These technologies may be effective at blocking multiple mechanisms of ischemia- reperfusion injury (IRI) and improving renal transplant outcomes. This review addresses the mechanisms of renal IRI, examines the potential for NMP as a platform for pretransplant allograft modulation, and discusses the introduction of various therapies in this setting.

Delayed graft function is associated with an increased rate of renal allograft rejection: A retrospective single center analysis

INTRODUCTION

The association of delayed graft function (DGF) and biopsy proven acute rejection (BPAR) of renal allografts is controversial. Borderline rejections comprise a major portion of biopsy results but the significance of such histologic changes is debated. The present study explores the impact of DGF on BPAR with a special emphasis on discriminating the effects of borderline rejection.

METHODS

Single center analysis of 417 deceased donor kidney recipients (age>18; transplantation date 1/2008-2/2015). Patients with primary non-function were excluded. DGF was defined as the need for dialysis within the first week after transplantation. Acute rejection was defined according to Banff criteria. Cox proportional hazards models were used to examine the relationship of DGF with BPAR within the first year.

RESULTS

No graft loss was observed during the first year after transplantation. DGF significantly associated with BPAR in the first year, irrespective of whether borderline rejections were included (HR 1.71, 95%CI 1.16,2.53) or excluded (HR 1.79, 95%CI 1.13,2.84).

CONCLUSION

DGF is significantly associated with rejection-with or without borderline changes-within the first year.

Ischemia-Reperfusion Injury Reduces Long Term Renal Graft Survival: Mechanism and Beyond

Ischemia-reperfusion injury (IRI) during renal transplantation often initiates non-specific inflammatory responses that can result in the loss of kidney graft viability. However, the long-term consequence of IRI on renal grafts survival is uncertain. Here we review clinical evidence and laboratory studies, and elucidate the association between early IRI and later graft loss. Our critical analysis of previous publications indicates that early IRI does contribute to later graft loss through reduction of renal functional mass, graft vascular injury, and chronic hypoxia, as well as subsequent fibrosis. IRI is also known to induce kidney allograft dysfunction and acute rejection, reducing graft survival. Therefore, attempts have been made to substitute traditional preserving solutions with novel agents, yielding promising results.

•

Ischaemia reperfusion injury (IRI) potentiates delayed renal graft function and causes reduction in renal graft survival

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IRI causes innate immune system activation, hypoxic injury, inflammation and graft vascular disease

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Reducing prolonged cold ischaemic time improves graft survival

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Novel protective strategies include mesenchymal stem cells, machine perfusion, and ex vivo preservation solution saturated with gas.

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Further studies are needed to investigate the long-term effects of novel ex vivo preservation agents

Comparison of graft and patient outcomes following kidney transplantation in extended hour and conventional haemodialysis patients

AIM

Differences in early graft function between kidney transplant recipients previously managed with either haemodialysis (HD) or peritoneal dialysis are well described. However, only two single-centre studies have compared graft and patient outcomes between extended hour and conventional HD patients, with conflicting results.

METHODS

This study compared the outcomes of all extended hour (≥24 h/week) and conventional HD patients transplanted in Australia and New Zealand between 2000 and 2014. The primary outcome was delayed graft function (DGF), defined in an ordinal manner as either a spontaneous fall in serum creatinine of less than 10% within 24 h, or the need for dialysis within 72 h following transplantation. Secondary outcomes included the requirement for dialysis within 72 h post-transplant, acute rejection, estimated glomerular filtration rate at 12 months, death-censored graft failure, all-cause and cardiovascular mortality, and a composite of graft failure and mortality.

RESULTS

A total of 4935 HD patients (378 extended hour HD, 4557 conventional HD) received a kidney transplant during the study period. Extended hour HD was associated with an increased likelihood of DGF compared with conventional HD (adjusted proportional odds ratio 1.33; 95% confidence interval 1.06-1.67). There was no significant difference between extended hour and conventional HD in terms of any of the secondary outcomes.

CONCLUSION

Compared to conventional HD, extended hour HD was associated with DGF, although long-term graft and patient outcomes were not different.

Evaluation of predictive models for delayed graft function of deceased kidney transplantation

Background

This study aimed to evaluate the predictive power of five available delayed graft function (DGF)-prediction models for kidney transplants in the Chinese population.

Results

Among the five models, the Irish 2010 model scored the best in performance for the Chinese population. Irish 2010 model had an area under the receiver operating characteristic (ROC) curve of 0.737. Hosmer-Lemeshow goodness-of-fit test showed that the Irish 2010 model had a strong correlation between the calculated DGF risk and the observed DGF incidence (p = 0.887). When Irish 2010 model was used in the clinic, the optimal upper cut-off was set to 0.5 with the best positive likelihood ratio, while the lower cut-off was set to 0.1 with the best negative likelihood ratio. In the subgroup of donor aged ≤ 5, the observed DGF incidence was significantly higher than the calculated DGF risk by Irish 2010 model (27% vs. 9%).

Materials and Methods

A total of 711 renal transplant cases using deceased donors from China Donation after Citizen's Death Program at our center between February 2007 and August 2016 were included in the analysis using the five predictive models (Irish 2010, Irish 2003, Chaphal 2014, Zaza 2015, Jeldres 2009).

Conclusions

Irish 2010 model has the best predictive power for DGF risk in Chinese population among the five models. However, it may not be suitable for allograft recipients whose donor aged ≤ 5-year-old.

Death with graft function after kidney transplantation: a single-center experience

BACKGROUND

Death with graft function (DWGF) is an important cause of long-term loss of grafts and patients. In this study, we investigated clinical characteristics and causes of DWGF in kidney transplant recipients.

METHODS

We recruited kidney allograft recipients who underwent surgery during 1973-2016 at Seoul National University Hospital in Korea (n = 2137). We divided recipients into four groups: alive with graft function (AWGF), alive with graft loss (AWGL), DWGF, and death with graft loss (DWGL).

RESULTS

Among 455 recipients with graft loss, 88 (19.3%) lost graft function due to death. DWGF was responsible for 38.6% of a total of 228 deaths. Recipients with DWGF were older, more often diabetic, and experienced delayed graft function more often compared to patients with AWGF, AWGL, and DWGL. Additionally, they had fewer episodes of acute rejection than AWGF and AWGL patients. The majority of DWGF developed because of infection (40.9%), malignancy (28.4%), and cardiovascular disease (11.4%). Infection-related mortality was highest within the first year after transplantation. Death due to malignancy was lowest within the first year, but increased thereafter.

CONCLUSIONS

In our center, DWGF was a significant cause of graft loss. Infection and malignancy were the leading causes of DWGF during the overall post-transplantation period. Therefore, close monitoring for infection and malignancy should be instituted to lessen the burden of graft loss.

ICU Management of the Potential Organ Donor: State of the Art

End-organ failure is associated with high mortality and morbidity, in addition to increased health care costs. Organ transplantation is the only definitive treatment that can improve survival and quality of life in such patients; however, due to the persistent mismatch between organ supply and demand, waiting lists continue to grow across the world. Careful intensive care management of the potential organ donor with goal-directed therapy has the potential to optimize organ function and improve donation yield.

Organ donation protocols

Organ transplantation improves survival and quality of life in patients with end-organ failure. Waiting lists continue to grow across the world despite remarkable advances in the transplantation process, from the creation of public engagement campaigns to the development of critical pathways for the timely identification, referral, approach, and treatment of the potential organ donor. The pathophysiology of dying triggers systemic changes that are intimately related to organ viability. The intensive care management of the potential organ donor optimizes organ function and improves the donation yield, representing a significant step in reducing the mismatch between organ supply and demand. Different beliefs and cultures reflect diverse legislations and donation practices amongst different countries, creating a challenge to standardized practices. Maintaining public trust is necessary for continued progress in organ donation and transplantation, hence the urge for a joint effort in creating uniform protocols that ensure transparent practices within the medical community.

Prediction, prevention, and management of delayed graft function: where are we now?

Delayed graft function (DGF) remains a major barrier to improved outcomes after kidney transplantation. High-risk transplant recipients can be identified, but no definitive prediction model exists. Novel biomarkers to predict DGF in the first hours post-transplant, such as neutrophil gelatinase-associated lipocalin (NGAL), are under investigation. Donor management to minimize the profound physiological consequences of brain death is highly complex. A hormonal resuscitation package to manage the catecholamine "storm" that follows brain death is recommended. Donor pretreatment with dopamine prior to procurement lowers the rate of DGF. Hypothermic machine perfusion may offer a significant reduction in the rate of DGF vs simple cold storage, but costs need to be evaluated. Surgically, reducing warm ischemia time may be advantageous. Research into recipient preconditioning options has so far not generated clinically helpful interventions. Diagnostic criteria for DGF vary, but requirement for dialysis and/or persistent high serum creatinine is likely to remain key to diagnosis until current work on early biomarkers has progressed further. Management centers on close monitoring of graft (non)function and physiological parameters. With so many unanswered questions, substantial reductions in the toll of DGF in the near future seem unlikely but concentrated research on many levels offers long-term promise.

Sex and the single transplanted kidney

Substantial ischemia-reperfusion injury (IRI) to the transplanted kidney occurs in 30% to 50% of transplantation patients who receive the organ from a deceased donor. IRI usually manifests as delayed graft function (DGF) and, in severe cases, results in primary nonfunction. Previous studies, primarily experimental, have demonstrated sex-specific susceptibility to IRI in kidney and other organs. In this issue of the JCI, Aufhauser Jr., Wang, and colleagues further demonstrate the importance of donor and recipient sex in IRI and elucidate the role of estrogen receptors in a murine model. Furthermore, analysis of data from 46,691 renal transplant patients in the United Network for Organ Sharing (UNOS) database revealed that sex affects DGF outcomes in humans. Manipulation of sex-driven molecular pathways offers a fertile opportunity to increase the number of organs available for transplantation and to reduce IRI in kidney and, likely, other organs.