Delayed graft function requiring more than one-time dialysis treatment is associated with inferior clinical outcomes

The Dual-specificity Phosphatase 3 (DUSP3): A Potential Target Against Renal Ischemia/Reperfusion Injury

Renal ischemia/reperfusion (I/R) injury is a common clinical challenge faced by clinicians in kidney transplantation. I/R is the leading cause of acute kidney injury, and it occurs when blood flow to the kidney is interrupted and subsequently restored. I/R impairs renal function in both short and long terms. Renal ischemic preconditioning refers to all maneuvers intended to prevent or attenuate ischemic damage. In this context, the present review focuses on the dual-specificity phosphatase 3 (DUSP3), also known as vaccinia H1-related phosphatase, an uncommon regulator of mitogen-activated protein kinase (MAPK) phosphorylation. DUSP3 has different biological functions: (1) it acts as a tumor modulator and (2) it is involved in the regulation of immune response, thrombosis, hemostasis, angiogenesis, and genomic stability. These functions occur either through MAPK-dependent or MAPK-independent mechanisms. DUSP3 genetic deletion dampens kidney damage and inflammation caused by I/R in mice, suggesting DUSP3 as a potential target for preventing renal I/R injury. Here, we discuss the putative role of DUSP3 in ischemic preconditioning and the potential mechanisms of such an attenuated inflammatory response via improved kidney perfusion and adequate innate immune response.

Delayed Graft Function Duration in Deceased Donor Kidney Transplants

BACKGROUND

Delayed graft function (DGF) is an important prognostic indicator after kidney transplantation. Depending on the severity of the ischemia-reperfusion injury, DGF can have several clinical presentations, with different renal function recovery times. Both the presence and duration of DGF can have an impact on kidney transplantation outcomes. However, the definition of the cutoff point, above which the outcomes are worse, varies widely in the literature.

METHODS

To investigate the impact of DGF and its duration on patient and graft survivals, a single-center retrospective study including all deceased donor kidney transplants was performed between November 2008 and December 2015 (n = 188). Through the analysis on the receiver operating characteristic curve, the cutoff point that determined the worst outcome was reached. DGF patients were then divided according to the duration of DGF (<8 days or ≥8 days).

RESULTS

The overall incidence of DGF was 62.2%. Higher HLA mismatches was an independent risk factor for prolonged DGF. DGF ≥8 days was associated with acute rejection and this one was associated with patient death in 3 years.

CONCLUSION

DGF with a duration of more than 8 days associated with higher HLA mismatches increases the risk of acute rejection, but graft loss and patient survival are not affected by DGF, regardless of its duration.

Duration of delayed graft function and its impact on graft outcomes in deceased donor kidney transplantation

BACKGROUND

There is controversy regarding the impact of delayed graft function (DGF) on kidney transplant outcomes. We hypothesize that the duration of DGF, rather than DGF itself, is associated with long-term kidney graft function.

METHODS

We analyzed all deceased donor kidney transplants (DDKT) done at our center between 2008 to 2020. We determined factors associated with DGF duration. DGF duration was assessed at three 14-day intervals: < 14 DGF days, 14-27 DGF days, > 28 DGF days. We studied the impact of DGF duration on survival and graft function and resource utilization, including hospital length of stay and readmissions.

RESULTS

1714 DDKT recipients were included, 59.4% (n = 1018) had DGF. The median DGF duration was 10 days IQR (6,15). The majority of recipients (95%) had resolution of DGF within 28 days. Donor factors associated with DGF days were longer cold ischemia time, donor on inotropes, older age, donation after circulatory death, higher terminal creatinine, and hypertension. Recipient factors associated with increased DGF duration included male sex, length on dialysis before transplant, and higher body mass index. There were no differences in acute rejection events or interstitial fibrosis progression by 4 months when comparing DGF days. The median length of stay was 3 days. However, readmissions increased with increasing DGF duration. Death-censored graft survival was not associated with the length of DGF except when DGF lasted > 28 days.

CONCLUSIONS

Inferior graft survival was observed only in recipients of DDKT with DGF lasting beyond 28 days. DGF lasting < 28 days had no impact on graft survival. Duration of DGF, rather than DGF itself, is associated with graft survival.

TRIAL REGISTRATION

Retrospective study approved by Mayo Clinic IRB number ID: 20-011561.

Tubular Cell Dropout in Preimplantation Deceased Donor Biopsies as a Predictor of Delayed Graft Function

Supplemental Digital Content is available in the text.

Background.

Delayed graft function (DGF) affects over 25% of deceased donor kidney transplants (DDKTs) and is associated with increased cost, worsened graft outcomes, and mortality. While approaches to preventing DGF have focused on minimizing cold ischemia, donor factors such as acute tubular injury can influence risk. There are currently no pharmacologic therapies to modify DGF risk or promote repair, in part due to our incomplete understanding of the biology of preimplantation tubular injury.

Methods.

We collected intraoperative, preimplantation kidney biopsies from 11 high-risk deceased donors and 10 living donors and followed transplant recipients for graft function. We performed quantitative high-dimensional histopathologic analysis using imaging mass cytometry to determine the cellular signatures that distinguished deceased and living donor biopsies as well as deceased donor biopsies which either did or did not progress to DGF.

Results.

We noted decreased tubular cells (P < 0.0001) and increased macrophage infiltration (P = 0.0037) in high-risk DDKT compared with living donor biopsies. For those high-risk DDKTs that developed postimplant DGF (n = 6), quantitative imaging mass cytometry analysis showed a trend toward reduced tubular cells (P = 0.02) and increased stromal cells (P = 0.04) versus those that did not (n = 5). Notably, these differences were not identified by conventional histopathologic evaluation.

Conclusions.

The current study identifies donor tubular cell loss as a precursor of DGF pathogenesis and highlights an area for further investigation and potential therapeutic intervention.

Poor kidney graft survival in anorexia nervosa patients

BACKGROUND

Anorexia nervosa is a condition associated with poor outcomes in a variety of circumstances such as recurrence of eating disorders, psychiatric disorders, and organ damage.

OBJECTIVE

In the present study, we first sought to determine the 5-year kidney graft survival in patients with anorexia nervosa and then to evaluate the BMI course and medical complications.

METHODS

In this multicenter, retrospective, case-control study, we analyzed the impact of anorexia nervosa on graft outcomes compared to transplant recipients with low or normal BMI.

RESULTS

We enrolled 137 women in this study: 19 with anorexia nervosa, 59 with low BMI (BMI < 18.5 kg/m²), and 59 with normal BMI (18.5-24.9 kg/m²). Anorexia nervosa was significantly associated with lower graft survival compared to either of the other groups (hazard ratio 5.5 [95% CI 3.4-8.9], p = 0.005); there was no difference in graft survival between patients with low or normal BMI. Cardiovascular complications were more frequent in the anorexia nervosa group (37%) than in patients with low (6%) or normal BMI (7%) (p = 0.001).

CONCLUSION

We conclude that patients with anorexia nervosa should be considered a high-risk group.

LEVEL OF EVIDENCE

Level III, evidence obtained from well-designed cohort or case-control analytic studies.

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.

[Ischemia-reperfusion injury after kidney transplantation]

Ischemia-reperfusion injury is an inescapable phenomenon in kidney transplantation. It combines lesional processes of biochemical origin associated with oxydative stress and of immunological origin in connection with the recruitment and activation of innate immunity cells. Histological lesions associate acute tubular necrosis and interstitial œdema, which can progress to interstitial fibrosis. The extent of these lesions depends on donor characteristics (age, expanded criteria donor, etc.) and cold ischemia time. In the short term, ischemia-reperfusion results in delayed recovery of graft function. Cold ischemia time also impacts long-term graft survival. Preclinical models, such as murine and porcine models, have furthered understanding of the pathophysiological mechanisms of ischemia-reperfusion injury. Due to its renal anatomical proximity to humans, the porcine model is relevant to assessment of the molecules administered to a donor or recipient, and also of additives to preservation solutions. Different donor resuscitation and graft perfusion strategies can be studied. In humans, prevention of ischemia-reperfusion injury is a research subject as concerns donor conditioning, additive molecules in preservation solutions, graft reperfusion modalities and choice of the molecules administered to the recipient. Pending significant advances in research, the goal is to achieve the shortest possible cold ischemia time.

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.

Hemodialysis or Peritoneal Dialysis, Which Is Better for Patients with Delayed Graft Function?

BACKGROUND/AIMS

Hemodialysis (HD) or peritoneal dialysis (PD) is an important renal replacement method in patients with delayed graft function (DGF) after kidney transplantation; however, it is not clear which dialysis modality is superior. This study determined the impact of different dialysis modalities on patients with DGF.

METHODS

It was a single-center, retrospective and descriptive study. We performed 673 kidney transplants from donors after cardiac death (DCD) between January 2010 and December 2016 at our center and 138 (20.5%) recipients developed DGF after transplantation. We classified the recipients into two groups according to post-transplant dialysis: DGF-HD (n=96) and DGF-PD (n=42). We analyzed the outcomes of the different dialysis modalities 30 days and 1 year post-transplantation.

RESULTS

There were no differences in baseline factors between patients with post-transplant HD (n = 96) or PD (n = 42). There were 10 patients with conversion from PD to HD during DGF. The DGF-PD patients had a higher rate of treatment failure than the DGF-HD patients (23.8% vs. 0%, p < 0.001), peritonitis (7.1% vs. 0%, p = 0.027), and longer duration of dialysis dependence (10.5 vs. 9 days, p = 0.003). There was no statistically significant difference between both groups with respect to acute rejection, hemorrhage, and patient and graft survival at 1 year.

CONCLUSION

In renal transplant recipients with DGF, post-transplant PD led to increased treatment failure. PD did not result in rapid recovery of transplanted renal function, and had a high probability of peritonitis.

Long-term effects of delayed graft function duration on function and survival of deceased donor kidney transplants

Introduction:

Delayed graft function (DGF) is a frequent complication after deceased donor kidney transplantation with an impact on the prognosis of the transplant. Despite this, long-term impact of DGF on graft function after deceased donor kidney transplantation has not been properly evaluated.

Objective:

The main objective of this study was to evaluate risk factors for DGF and the impact of its occurrence and length on graft survival and function.

Methods:

A retrospective cohort study was performed in 517 kidney transplant recipients who received a deceased donor organ between January 2008 and December 2013.

Results:

The incidence of DGF was 69.3% and it was independently associated with donor's final serum creatinine and age, cold ischemia time, use of antibody induction therapy and recipient's diabetes mellitus. The occurrence of DGF was also associated with a higher incidence of Banff ≥ 1A grade acute rejection (P = 0.017), lower graft function up to six years after transplantation and lower death-censored graft survival at 1 and 5 years (P < 0.05). DGF period longer than 14 days was associated with higher incidence of death-censored graft loss (P = 0.038) and poorer graft function (P < 0.001). No differences were found in patient survival.

Conclusions:

The occurrence of DGF has a long-lasting detrimental impact on graft function and survival and this impact is even more pronounced when DGF lasts longer than two weeks.

Decoding cold ischaemia time impact on kidney graft: the kinetics of the unfolded protein response pathways

The relationship between cold ischaemia time (CIT) and adverse outcome is now acknowledged. However, the underlying mechanisms remain to be defined, which slows the development of adapted therapeutics and diagnostics. We explored the impact of CIT in both preclinical and in vitro models of preservation. We determined that the endoplasmic reticulum (ER) and its stress response (unfolded protein response, UPR) were regulated in close association with CIT; the eIF2α-ATF4 pathway was inhibited early (1-8 h) at the detriment of cell survival, while the ATF6 pathway was activated late (12-24 h) and associated with cell death. The IRE1α-XBP1 branch was activated at reperfusion only if CIT extended beyond 8 h, and had a dual role on cell fate - deleterious through IRE1's RNase activity and beneficial through IRE1α other roles. Finally, the pro-apoptotic factor CHOP was a common target of both ATF6 and IRE1α pathways and was associated with elongated CIT and increased cell death. Microarray analysis of human transplanted kidney confirmed that UPR markers were regulated by CIT and that CHOP was associated with adverse outcome. We show that UPR could be a critical pathway explaining the relationship between CIT and graft outcome, highlighting the potential for UPR-based therapeutics and diagnostics to improve transplantation.

The prognostic value of the furosemide stress test in predicting delayed graft function following deceased donor kidney transplantation

OBJECTIVES AND METHODS

The Furosemide Stress Test (FST) is a novel dynamic assessment of tubular function that has been shown in preliminary studies to predict patients who will progress to advanced stage acute kidney injury, including those who receive renal replacement therapy (RRT). The aim of this study is to investigate if the urinary response to a single intraoperative dose of intravenous furosemide predicts delayed graft function (DGF) in patients undergoing deceased donor kidney transplant.

RESULTS

On an adjusted multiple logistic regression, a single 100 mg dose of intraoperative furosemide after the anastomosis of the renal vessels (FST) predicted the need for RRT at 2 and 6 h post kidney transplantation (KT). Recipient urinary output was measured at 2 and 6 h post furosemide administration. In receiver-operating characteristic (ROC) analysis, the FST predicted DGF with an area-under-the curve of 0.85 at an optimal urinary output cut-off of <600 mls at 6 h with a sensitivity of and a specificity of 83% and 74%, respectively.

CONCLUSIONS

The FST is a predictor of DGF post kidney transplant and has the potential to identify patients requiring RRT early after KT.

Factors Associated With Delayed Graft Function and Their Influence on Outcomes of Kidney Transplantation

BACKGROUND

One of the main postoperative complications of kidney transplant is delayed graft function (DGF), which means absence of graft function after transplant or the need for dialysis during the first week post procedure. The occurrence of DGF currently in our hospital is high and has been attributed to a combination of many factors. The aim of this study was to evaluate the factors associated to DGF and their influence in the outcome of kidney transplants.

METHODS

Historical cohort of 150 patients transplanted with live or deceased donor kidneys from 2011 to 2013.

RESULTS

DGF was associated to time in dialysis and the number of recipient pre-transplant transfusions, donors age, serum creatinine level, use of vasoactive drugs in the donor, distance from place of organ retrieval and transplant center, and duration of cold ischemia time. DGF influenced post-transplantation outcome in regard to length of stay in intensive care, length of hospital stay, acute rejection episodes, and higher creatinine levels at discharge. Patients and graft survival were shorter in the DGF group.

CONCLUSIONS

There are multiple factors related to DGF, the most important being those related to donors, and organ storage. The most important factor related to the recipient was the dialysis vintage. We did not find a correlation between DGF and HLA-compatibility. DGF consequences are important, including worse graft function and survival, as well as impact in recipient morbidity and mortality.

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.

Efficacy of everolimus with reduced-exposure cyclosporine in de novo kidney transplant patients at increased risk for efficacy events: analysis of a randomized trial

The efficacy of de novo everolimus with reduced-exposure calcineurin inhibitor (CNI) was examined in kidney transplant subpopulations from the A2309 study that were identified to be at increased risk for efficacy events. A2309 was a 24-month, multicenter, open-label trial in which 833 de novo kidney transplant recipients were randomized to everolimus targeting 3-8 or 6-12 ng/ml with reduced-exposure cyclosporine (CsA), or mycophenolic acid (MPA) with standard-exposure CsA, all with basiliximab induction. The composite efficacy endpoint was treated biopsy-proven acute rejection (BPAR), graft loss, death, or loss to follow-up. Cox proportional hazard modeling showed male gender, younger recipient age, black race, delayed graft function, human leukocyte antigen (HLA) mismatch ≥3 and increasing donor age to be significantly predictive for the composite efficacy endpoint at months 12 or 24 post-transplant. CsA exposure was 53-75 % lower, and 46-75 % lower, in patients receiving everolimus 3-8 ng/ml or receiving everolimus 6-12 ng/ml, respectively, versus MPA-treated patients. The incidence of the composite endpoint was similar in all three treatment groups within each subpopulation analyzed. The incidence of treated BPAR was similar with everolimus 3-8 ng/ml or MPA in all subpopulations, but less frequent with everolimus 6-12 ng/ml versus MPA in patients with HLA mismatch ≥3 (p = 0.049). This post hoc analysis of a large, randomized trial suggests that a de novo regimen of everolimus with reduced-exposure CsA maintains immunosuppressive efficacy even in kidney transplant patients at increased risk for efficacy events despite substantial reductions in CsA exposure.

Molecular pathogenesis of post-transplant acute kidney injury: assessment of whole-genome mRNA and miRNA profiles

Acute kidney injury (AKI) affects roughly 25% of all recipients of deceased donor organs. The prevention of post-transplant AKI is still an unmet clinical need. We prospectively collected zero-hour, indication as well as protocol kidney biopsies from 166 allografts between 2011 and 2013. In this cohort eight cases with AKI and ten matched allografts without pathology serving as control group were identified with a follow-up biopsy within the first twelve days after engraftment. For this set the zero-hour and follow-up biopsies were subjected to genome wide microRNA and mRNA profiling and analysis, followed by validation in independent expression profiles of 42 AKI and 21 protocol biopsies for strictly controlling the false discovery rate. Follow-up biopsies of AKI allografts compared to time-matched protocol biopsies, further baseline adjustment for zero-hour biopsy expression level and validation in independent datasets, revealed a molecular AKI signature holding 20 mRNAs and two miRNAs (miR-182-5p and miR-21-3p). Next to several established biomarkers such as lipocalin-2 also novel candidates of interest were identified in the signature. In further experimental evaluation the elevated transcript expression level of the secretory leukocyte peptidase inhibitor (SLPI) in AKI allografts was confirmed in plasma and urine on the protein level (p<0.001 and p = 0.003, respectively). miR-182-5p was identified as a molecular regulator of post-transplant AKI, strongly correlated with global gene expression changes during AKI. In summary, we identified an AKI-specific molecular signature providing the ground for novel biomarkers and target candidates such as SLPI and miR-182-5p in addressing AKI.

Pre-transplant immune state defined by serum markers and alloreactivity predicts acute rejection after living donor kidney transplantation

Acute rejection (AR) remains a major cause for long-term kidney allograft failure. Reliable immunological parameters suitable to define the pre-transplant immune state and hence the individual risk of graft rejection are highly desired to preferably adapt the immunosuppressive regimen in advance. Donor and third party alloreactivities were determined by mixed lymphocyte cultures. Soluble forms of CD25, CD30, and CD44 were detected in patients' serum by ELISA. Various lymphocyte subpopulations were measured using flow cytometry. All patients received triple immunosuppression (tacrolimus/mycophenolate mofetil/steroids) and were grouped according to biopsy results within the first year: rejection-free (RF, n = 13), borderline (BL, n = 5), or acute rejection (AR, n = 7). Patients with AR showed the highest pre-transplant alloreactivities and serum levels (sCD25/sCD30/sCD44) according to the pattern RF < BL < AR. Relying on serum analysis only, multivariate logistic regression (logit link function) yielded a prognostic score for prediction of rejection with 75.0% sensitivity and 69.2% specificity. Patients with rejection showed markedly higher pre-transplant frequencies of CD4(+) /CD8(+) T cells lacking CD28, but lower numbers of CD8(+) CD161(bright) T cells and NK cells than RF individuals. Pre-transplant immune state defined by alloreactivity, serum markers, and particular lymphocyte subsets seems to correlate with occurrence of graft rejection after kidney transplantation. A prognostic score based on pre-transplant serum levels has shown great potential for prediction of rejection episodes and should be further evaluated.

Delayed graft function: risk factors and the effects of early function and graft survival

INTRODUCTION

Delayed graft function (DGF), a well-known immediate postoperative complication is defined as the need for dialysis during the first week after deceased donor kidney transplantation. It affects 25% to 50% of recipients. In this study we identified risk factors for DGF and its impact on patient and graft survivals.

METHODS

We retrospectively analyzed medical records from renal transplant recipients aged above 18 years who received a deceased donor kidney graft between November 2008 and December 2011, excluding kidney losses during the first week.

RESULTS

Among 137 transplantations, 64 (46.5%) displayed DGF. Multivariate analysis showed secondary renal disease (OR 3.7, CI 1.36-10.30; P = .011), HLA mismatches > 3 (OR 4.4, CI 1.53-12.51; P = .006) and donor urine output ≤ 3000 ml/24h (OR 25.8, CI 3.60-185.70; P = .001) to be significant risk factors for DGF. The hospitalization time was longer in the DGF group (38,2 ± 20,75 vs. 25,6 ± 8,18; P < .001). At 1 month, DGF group showed worse graft function based upon serum creatinine: 207.7 ± 148.52 vs 118.1 ± 36.63 μmol/L (P < .001). At 1 year follow-up, incidence of biopsy-proven acute renal rejection episodes was higher in the DGF (28; 51,9%) vs. the non-DGF group (18; 33,3%; P = .05). The 1-year recipient survival in DGF and no DGF groups were 90% vs 97% respectively (P = .124). With 1-year death censored graft survivals of 92% vs 100% respectively (P = .062).

CONCLUSION

Secondary renal disease, HLA mismatches and lower donor urinary output were associated with a greater incidence of DGF, leading to prolonged hospitalizations and an increased risk for an acute rejection episode.

The prognostic value of time needed on dialysis in patients with delayed graft function

INTRODUCTION

We hypothesize that in patients with delayed graft function (DGF), the need for a longer time needed on dialysis (TND) post-kidney transplant is associated with poorer long-term function and an increase in complications.

METHODS

This was a retrospective chart review involving collaboration between Western University (WU) Renal Transplant Program of London, Ontario and the Saskatchewan renal transplant program (SRTP). A total of 774 patients (567 WU and 207 SRTP) received kidney transplants between 2004 and 2011, of which 83 patients with deceased donor transplants (59 WU and 24 SRTP) developed DGF, defined as the need for dialysis in the first week posttransplant.

RESULTS

Patients with DGF were divided into three groups depending on TND [group 1: <7 days (n = 52), group 2: 7-14 days (n = 13) and group 3 (n = 18): >14 days]. The creatinine clearance (CrCl) at 30 days (42.5, 33.8, 20.0 cc/min; P < 0.001) and 1 year (56.7, 49.2, 37.3 cc/min, P = 0.031) were significantly different between the three groups. Multivariate regression analysis identified length of TND posttransplant (β = -0.5, P < 0.001) and donation after cardiac death (DCD) donor (β = 19.5, P < 0.001) as the most significant predictors of CrCl at 1 year in these patients with DGF. DCD kidneys with DGF had a higher CrCl at 1 year and fewer readmissions in the first year compared with non-DCD kidneys with DGF.

DISCUSSION

Our study suggests that increased TND is associated with worse CrCl at 1 year. The data also support the hypothesis of a different mechanism for DGF in DCD and non-DCD kidneys.

The effects of preoperative immunosuppressive therapy on ischemia and reperfusion (I/R) injury in healthy rats

PURPOSE

Warm-ischemia-induced injuries might be encountered during renal transplants from cadavers and healthy donors. Toll-like receptors (TLR) in ischemia-reperfusion (I/R) injury are one of the indicators of intracellular injury pathways. The intensity of ischemic injury is directly proportionate to high TLR levels. To minimize the I/R injury, we investigated TLR2 and TLR4 levels on rats, which were pretreated with tacrolimus (FK506) before I/R.

METHODS

Eight Wistar albino rats in the study group were administered .01 mg/kg intramuscular tacrolimus. Administration to the study group was performed 24 and 1 h before warm ischemia. Eight rats in the control group were injected with 0.1 c.c. of distilled water. Blood samples were collected from the tail veins of all the rats on the first, second and third days. Expression levels of TLR2 and TLR4 genes were analyzed using the polymerase chain reaction method, to determine any significant difference between the control and study groups on the days when blood was taken.

RESULTS

TLR2 (p = 0.045) and TLR4 (p = 0.022) levels in the study group were found to be statistically, and significantly, lower than those in the control group, on the second day following warm-ischemia- and reperfusion-induced injury.

CONCLUSIONS

Administration of immunosuppressive drugs to healthy donor rats led to a statistically significant reduction in the expression levels of TLR2 and TLR4 in the early period. In light of the data obtained by this study, we hypothesize that a preoperative therapy on donors might have a role in preventing I/R injury.