Delayed graft function and the risk of death with graft function in living donor kidney transplant recipients

Delayed Graft Function in Kidney Transplant: Risk Factors, Consequences and Prevention Strategies

Background. Delayed graft function is a frequent complication of kidney transplantation that requires dialysis in the first week posttransplant. Materials and Methods. We searched for the most relevant articles in the National Institutes of Health library of medicine, as well as in transplantation, pharmacologic, and nephrological journals. Results. The main factors that may influence the development of delayed graft function (DGF) are ischemia–reperfusion injury, the source and the quality of the donated kidney, and the clinical management of the recipient. The pathophysiology of ischemia–reperfusion injury is complex and involves kidney hypoxia related to the duration of warm and cold ischemia, as well as the harmful effects of blood reperfusion on tubular epithelial cells and endothelial cells. Ischemia–reperfusion injury is more frequent and severe in kidneys from deceased donors than in those from living donors. Of great importance is the quality and function of the donated kidney. Kidneys from living donors and those with normal function can provide better results. In the peri-operative management of the recipient, great attention should be paid to hemodynamic stability and blood pressure; nephrotoxic medicaments should be avoided. Over time, patients with DGF may present lower graft function and survival compared to transplant recipients without DGF. Maladaptation repair, mitochondrial dysfunction, and acute rejection may explain the worse long-term outcome in patients with DGF. Many different strategies meant to prevent DGF have been evaluated, but only prolonged perfusion of dopamine and hypothermic machine perfusion have proven to be of some benefit. Whenever possible, a preemptive transplant from living donor should be preferred.

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.

Urinary mitochondrial DNA associates with delayed graft function following renal transplantation

BACKGROUND

Ischaemia-reperfusion (IR) injury is an important determinant of delayed graft function (DGF) affecting allograft function. Mitochondrial DNA (mtDNA) is released upon cell death and platelet activation into the extracellular environment and has been suggested to be a biomarker in several diseases. Whether extracellular mtDNA accumulates in plasma and/or urine upon renal IR and predisposes DGF is unknown.

METHODS

C57BL/6J wild-type mice were subjected to renal IR. In addition, an observational case-control study was set up enrolling 43 patients who underwent kidney transplantation. One day post-IR in mice and a few days following renal transplantation in human, blood and urine were collected. Patients were stratified into DGF and non-DGF groups.

RESULTS

mtDNA-encoded genes accumulate in urine and plasma in both mice subjected to renal IR injury and in humans following renal transplantation. In human renal transplant recipients, cold ischaemia time and renal function correlate with urinary mtDNA levels. Urinary mtDNA levels but not urinary nuclear DNA levels were significantly higher in the DGF group compared with the non-DGF group. Multiple receiver operating characteristic curves revealed significant diagnostic performance for mtDNA-encoded genes cytochrome c oxidase III (COXIII); nicotinamide adenine dinucleotide hydrogen subunit 1 (NADH-deh); mitochondrially encoded, mitochondrially encoded nicotinamide adenine dinucleotide dehydrogenase 2 (MT-ND2) with an area under the curve of, respectively, 0.71 [P = 0.03; 95% confidence interval (CI) 0.54-0.89], 0.75 (P = 0.01; 95% CI 0.58-0.91) and 0.74 (P = 0.02; 95% CI 0.58-0.89).

CONCLUSIONS

These data suggest that renal ischaemia time determines the level of mtDNA accumulation in urine, which associates with renal allograft function and the diagnosis of DGF following renal transplantation.

Delayed kidney graft function in simultaneous pancreas-kidney transplant recipients is associated with early pancreas allograft failure

Delayed graft function (DGF) is a common complication associated with significant untoward effects in kidney-alone transplantation. The incidence and outcomes following kidney delayed graft function (K-DGF) among patients undergoing simultaneous pancreas-kidney (SPK) transplantation are less certain. We analyzed SPK recipients transplanted at our center between January 1994 and December 2017. A total of 632 recipients fulfilled the selection criteria, including 69 (11%) with K-DGF and 563 without. The incidence of K-DGF was significantly higher in recipients of organs from older donors and donation after circulatory death (DCD). The presence of K-DGF was significantly associated with an increased risk of pancreas graft failure during the first 90 days (n = 9, incidence rate [IR] 2.45/100 person-months), but not with late pancreas failure (n = 32, IR 0.84/100 person-months), kidney graft failure, or patient death. Although DCD was associated with K-DGF, it was not associated with either pancreas (hazard ratio [HR] 0.91, 95% CI 0.58-1.44, P = .69) or kidney (HR 1.09, 95% CI 0.66-1.82, P = .74) graft failure after adjustment for potential confounders. We found K-DGF to be a significant risk factor for pancreas graft failure but not kidney graft failure, with the major risk period being early (<90 days) posttransplant, and the major donor risk factor being older donor age.

Robot-Assisted versus Laparoscopic Donor Nephrectomy: A Comparison of 250 Cases

Living kidney donation is the best treatment for end-stage renal disease, however, the best surgical approach for minimally-invasive donor nephrectomy (DN) is still a matter of debate. This bi-centric study aimed to retrospectively compare perioperative outcomes and postoperative kidney function after 257 transperitoneal DNs including 52 robot-assisted (RDN) and 205 laparoscopic DNs (LDN). As primary outcomes, the intraoperative (operating time, warm ischemia time (WIT), major complications) and postoperative (length of stay, complications) results were compared. As secondary outcomes, postoperative kidney and graft function were analyzed including delayed graft function (DGF) rates, and the impact of the surgical approach was assessed. Overall, the type of minimally-invasive donor nephrectomy (RDN vs. LDN) did not affect primary outcomes, especially not operating time and WIT; and major complication and DGF rates were low in both groups. A history of smoking and preoperative kidney function, but not the surgical approach, were predictive for postoperative serum creatinine of the donor and recipient. To conclude, RDN and LDN have equivalent perioperative results in experienced centers. For this reason, not the surgical approach, but rather the graft- (preoperative kidney function) and patient-specific (history of smoking) aspects impacted postoperative kidney function.

Increased soluble fms-like tyrosine kinase 1 after ischemia reperfusion contributes to adverse clinical outcomes following kidney transplantation

Renal ischemia reperfusion injury (IRI) adversely affects clinical outcomes following kidney transplantation. Understanding the cellular mechanisms and the changes in gene/protein expression following IRI may help to improve these outcomes. Serum soluble fms-like tyrosine kinase 1 (sFlt-1), a circulating antiangiogenic protein, is increased in the first week following kidney transplantation. We evaluated the casual relationship of elevated sFlt-1 levels with renal microvascular dysfunction following IRI in a longitudinal study of 93 kidney transplant recipients and in several animal models. Transplant recipients with higher sFlt-1 levels had higher odds of delayed graft function, graft rejection, impaired graft function, and death. In a subgroup of 25 participants who underwent kidney biopsy within 4 months of kidney transplantation, peritubular capillary area was lower in those with elevated serum sFtl-1 levels. The administration of recombinant sFlt-1 into rodents resulted in significant structural and functional changes of the renal microvasculature, including reduced peritubular capillary density and intracapillary blood volume, and lead to increased expression of inflammatory genes and increased fibrosis. In a murine model of IRI, the kidney was a site of sFlt-1 production, and systemic neutralization of sFlt-1 preserved peritubular capillary density and alleviated renal fibrosis. Our data indicate that high sFlt-1 levels after IRI play an important role in the pathogenesis of microvascular dysfunction, thereby contributing to adverse clinical outcomes following kidney transplantation.

The recovery status from delayed graft function can predict long-term outcome after deceased donor kidney transplantation

The effect of delayed graft function (DGF) recovery on long-term graft outcome is unclear. The aim of this study was to examine the association of DGF recovery status with long-term outcome. We analyzed 385 recipients who underwent single kidney transplantation from brain-dead donors between 2004 and 2015. Patients were grouped according to renal function at 1 month post-transplantation: control (without DGF); recovered DGF (glomerular filtration rate [GFR] ≥ 30 mL/min/1.73 m²); and incompletely recovered DGF group (GFR < 30 mL/min/1.73 m²). DGF occurred in 104 of 385 (27%) recipients. Of the DGF patients, 70 recovered from DGF and 34 incompletely recovered from DGF. Death-censored graft survival rates for control, recovered DGF, and incompletely recovered DGF groups were 95.3%, 94.7%, and 80.7%, respectively, at 5 years post-transplantation (P = 0.003). Incompletely recovered DGF was an independent risk factor for death-censored graft loss (HR = 3.410, 95%CI, 1.114-10.437). DGF was associated with increased risk for patient death regardless of DGF recovery status. Mean GFRs at 5 years were 65.5 ± 20.8, 62.2 ± 27.0, and 45.8 ± 15.4 mL/min/1.73 m² for control, recovered, and incompletely recovered DGF groups, respectively (P < 0.001). Control group and recovered DGF patients had similar renal outcomes. However, DGF was associated with increased risk for patient death regardless of DGF recovery status.

Risk factors and outcomes of delayed graft function in renal transplant recipients receiving a steroid sparing immunosuppression protocol

AIM

To analyse the risk factors and outcomes of delayed graft function (DGF) in patients receiving a steroid sparing protocol.

METHODS

Four hundred and twenty-seven recipients of deceased donor kidney transplants were studied of which 135 (31.6%) experienced DGF. All patients received monoclonal antibody induction with a tacrolimus based, steroid sparing immunosuppression protocol.

RESULTS

Five year patient survival was 87.2% and 94.9% in the DGF and primary graft function (PGF) group respectively, P = 0.047. Allograft survival was 77.9% and 90.2% in the DGF and PGF group respectively, P < 0.001. Overall rejection free survival was no different between the DGF and PGF groups with a 1 and 5 year rejection free survival in the DGF group of 77.7% and 67.8% compared with 81.3% and 75.3% in the PGF group, P = 0.19. Patients with DGF who received IL2 receptor antibody induction were at significantly higher risk of rejection in the early post-transplant period than the group with DGF who received alemtuzumab induction. On multivariate analysis, risk factors for DGF were male recipients, recipients of black ethnicity, circulatory death donation, preformed DSA, increasing cold ischaemic time, older donor age and dialysis vintage.

CONCLUSION

Alemtuzumab induction may be of benefit in preventing early rejection episodes associated with DGF. Prospective trials are required to determine optimal immunotherapy protocols for patients at high risk of DGF.

Prolonged Ischemic Time, Delayed Graft Function, and Graft and Patient Outcomes in Live Donor Kidney Transplant Recipients

The association between prolonged cold ischemic time (CIT) and graft and patient outcomes in live donor kidney transplant recipients remains unclear. The aims of this study were to examine the association of CIT with delayed graft function and graft loss in live donor kidney transplant recipients and those who participated in the Australian Paired Kidney Exchange program using data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry. Of 3717 live donor transplant recipients between 1997 and 2012 who were followed for a median of 6.6 years (25 977 person-years), 224 (25%) experienced CIT >4-8 h. Donor age was an effect modifier between CIT and graft outcomes. In recipients who received kidneys from older donors aged >50 years, every hour of increase in CIT was associated with adjusted odds of 1.28 (95% confidence interval [CI] 1.07-1.53, p = 0.007) for delayed graft function, whereas CIT >4-8 h was associated with adjusted hazards of 1.93 (95% CI 1.21-3.09, p = 0.006) and 1.91 (95% CI 1.05-3.49, p = 0.035) for overall and death-censored graft loss, respectively, compared with CIT of 1-2 h. Attempts to reduce CIT in live donor kidney transplants involving older donor kidneys may lead to improvement of graft outcomes.

Outpatient Management of Delayed Graft Function Is Associated With Reduced Length of Stay Without an Increase in Adverse Events

Delayed graft function (DGF) is a common and costly complication of kidney transplantation. In July 2011, we established a multidisciplinary DGF clinic managed by nurse practitioners to facilitate early discharge and intensive management of DGF in the outpatient setting. We compared length of stay, 30-day readmission, acute rejection, and patient/graft survival in 697 consecutive deceased donor kidney transplantations performed between July 2009 and July 2014. Patients were divided into three groups: no DGF (n = 487), DGF before implementation of the DGF clinic (n = 118), and DGF clinic (n = 92). Baseline characteristics including age, gender, panel reactive antibody, retransplantation rates, HLA mismatches, induction, and maintenance immunosuppression were not significantly different between pre- and post-DGF clinic groups. Length of stay was significantly longer in pre-DGF clinic (10.9 ± 6.2 vs. 6.1 ± 2.1 days, p < 0.001). Thirty-day readmission (21% vs. 16%), graft loss (7% vs. 20%), and patient death (2% vs. 11%) did not differ significantly between pre- and post-DGF clinic. Patients in the DGF clinic were less likely to develop acute rejection (21% vs. 40%, p = 0.006). Outpatient management of DGF in a specialized clinic is associated with substantially shorter hospitalization and lower incidence of acute rejection without significant difference in 30-day readmission or patient and graft survival.

German recommendations for pretransplantation donor kidney biopsies

PURPOSE

This manuscript reviews the data about the histopathologic and develops recommendations to standardise and improve the biopsy procedure, the biopsy handling, the histopathological evaluation, the communication of results and the collection of data from pretransplantation kidney biopsies of deceased donors in Germany.

METHODS

The recommendations are based on this literature review, on discussions at two workshops held by the German Society of Pathology and the German Organ Transplantation Foundation and on personal experiences of the authors.

RESULTS

These German recommendations advocate the use of punch biopsies, paraffin embedding and detailed descriptive reporting of histopathological findings.

CONCLUSIONS

These recommendations constitute only a starting point. Periodical revisions will help to simplify and optimise the recommendations with the ultimate goal to prospectively gather data for the elaboration of a computer-based algorithm that allows the exact prediction of transplantation outcome for a given match of donor and recipient.

Kidneys from Older Living Donors Provide Excellent Short and Intermediate Outcomes--A Single China Center's Experience

BACKGROUND

Transplantation with kidneys from older living donors is on the rise, yet controversy still exists over whether the outcomes are as satisfactory as with kidneys from younger donors.

METHODS

We retrospectively analyzed 1009 living donor kidney transplants performed at our center between 2006 and 2013. Graft and patient outcomes were compared between transplants with kidneys from old living donors (OLD, 55-65 years) (n = 264) and from young living donors (YLD, <55 years) (n = 745).

RESULTS

The age was 32.80 ± 9.71 years and 33.91 ± 5.98 years for recipient in YLD and OLD group, respectively. Death-censored graft survival at 1, 3, and 5 years was 98.8%, 97.1%, and 95.8% in patients receiving YLD kidneys, similar to the corresponding values of 97.6%, 95.5% and 95.5% in patients receiving OLD kidneys (P = 0.356). Patient survival at 1, 3, and 5 years after transplantation was also similar for patients receiving YLD kidneys (98.5%, 97.1%, and 96.7%) and for patients receiving OLD kidneys (99.6%, 99.6%, and 96.8%; P = 0.110). The OLD kidneys were not associated with increased risk of death-censored graft failure (hazard ratio, 2.5; 95% confidence interval, 0.57 to 11.11) and patient death (hazard ratio, 1.67; 95% confidence interval, 0.75 to 3.73). In addition, there is no increased graft loss or patient death for each 10-year increase in donor age. Transplantation with OLD kidneys was not associated with reduced patient or graft outcomes in the short term (≤ 12 months) or medium term (>1 year).

CONCLUSIONS

Graft and patient outcomes after living-donor kidney transplantation are similar in the short-term and medium-term for donors aged 55 to 65 years and for younger donors. Therefore, the use of OLD kidneys should be encouraged in China.

Delayed graft function and the risk of acute rejection in the modern era of kidney transplantation

Delayed graft function (DGF) is commonly considered a risk factor for acute rejection, although this finding has not been uniformly observed across all studies. The link between DGF and acute rejection may have changed over time due to advances in immunosuppression and medical management. Here we conducted a cohort study of 645 patients over 12 years to evaluate the association of DGF and biopsy-proven acute rejection (BPAR) in a modern cohort of kidney transplant recipients. DGF was defined as the need for at least one dialysis session in the first week after kidney transplantation. The 1-, 3-, and 5-year cumulative probabilities of BPAR were 16.0, 21.8, and 22.6% in the DGF group, significantly different from the 10.1, 12.4, and 15.7% in the non-DGF group. In multivariable Cox proportional hazards model, the adjusted relative hazard for BPAR in DGF (vs. no DGF) was 1.55 (95% confidence interval (CI): 1.03, 2.32). This association was generally robust to different definitions of DGF. The relative hazard was also similarly elevated for T-cell- or antibody-mediated BPAR (1.52 (0.92, 2.51) and 1.54 (0.85, 2.77), respectively). Finally, the association was consistent across clinically relevant subgroups. Thus DGF remains an important risk factor for BPAR in a contemporary cohort of kidney transplant recipients. Interventions to reduce the risk of DGF and/or its aftereffects remain of paramount importance to improve kidney transplant outcomes.

The effect of delayed graft function on graft and patient survival in kidney transplantation: an approach using competing events analysis

OBJECTIVE

In kidney transplantation, the impact of delayed graft function (DGF) on long-term graft and patient survival is controversial. We examined the impact of DGF on graft and recipient survival by accounting for the possibility that death with graft function may act as a competing risk for allograft failure.

STUDY DESIGN AND SETTING

We used data from 1281 adult primary deceased-donor kidney recipients whose allografts functioned at least 1 year.

RESULTS

The probability of graft loss occurrence is overestimated using the complement of Kaplan-Meier estimates (1-KM). Both the cause-specific Cox proportional hazard regression model (standard Cox) and the subdistribution hazard regression model proposed by Fine and Gray showed that DGF was associated with shorter time to graft failure (csHR = 2.0, P = 0.002; sHR = 1.57, P = 0.009), independent of acute rejection (AR) and after adjusting for traditional factors associated with graft failure. Regarding patient survival, DGF was a predictor of patient death using the cause-specific Cox model (csHR = 1.57, P = 0.029) but not using the subdistribution model.

CONCLUSIONS

The probability of graft loss from competing end points should not be reported with the 1-KM. Application of a regression model for subdistribution hazard showed that, independent of AR, DGF has a detrimental effect on long-term graft survival, but not on patient survival.

Late acute rejection: incidence, risk factors, and effect on graft survival and function

Long-term graft survival and function has not kept pace with short-term success in kidney transplant (Tx) recipients. LAR ≥6 months post-Tx may contribute to lack of improvement; risk factors for LAR are not well known. Of 64 Tx recipients followed over six yr, 23 (35.9%) had LAR (LAR group) and 41 had no LAR (no LAR group). Of all variables, significant risk factors for LAR included DGF, (43.4% LAR vs. 14.6% in no LAR group, p = 0.0096); de novo DSA (65.2% vs. 26.8%, p = 0.003); mean COV% of TAC (41.8% vs. 34.6%, p = 0.03); and non-adherence (34.8% vs. 7.3%, p = 0.0043). DGF and DSA remained statistically significant (p = 0.002 and 0.003, respectively); COV% TAC had borderline significance (p = 0.057), and non-adherence was not significant on multivariate regression analysis. Patients with LAR had inferior graft survival and function, whereas graft function was stable in the no LAR group over a mean follow-up of 31.2 months. Patients with de novo DSA and DGF should be considered at risk of LAR; an early diagnosis and treatment of LAR may improve graft survival and function.

Renal ischemia-reperfusion injury amplifies the humoral immune response

Renal transplant recipients who experience delayed graft function have increased risks of rejection and long-term graft failure. Ischemic damage is the most common cause of delayed graft function, and although it is known that tissue inflammation accompanies renal ischemia, it is unknown whether renal ischemia affects the production of antibodies by B lymphocytes, which may lead to chronic humoral rejection and allograft failure. Here, mice immunized with a foreign antigen 24-96 hours after renal ischemia-reperfusion injury developed increased levels of antigen-specific IgG1 compared with sham-treated controls. This amplified IgG1 response did not follow unilateral ischemia, and it did not occur in response to a T-independent antigen. To test whether innate immune activation in the kidney after ischemia affects the systemic immune response to antigen, we repeated the immunization experiment using mice deficient in factor B that lack a functional alternative pathway of complement. Renal ischemia-reperfusion injury did not cause amplification of the antigen-specific antibodies in these mice, suggesting that the increased immune response requires a functional alternative pathway of complement. Taken together, these data suggest that ischemic renal injury leads to a rise in antibody production, which may be harmful to renal allografts, possibly explaining a mechanism underlying the link between delayed graft function and long-term allograft failure.

Efficacy and safety of thymoglobulin and basiliximab in kidney transplant patients at high risk for acute rejection and delayed graft function

OBJECTIVES

To compare the efficacy and safety of thymoglobulin compared with basiliximab in patients who had kidney transplants and are at high risk for acute rejection and delayed graft function.

MATERIALS AND METHODS

A retrospective review of patients who had 1 or more risk factors for acute rejection and delayed graft function and who were given either thymoglobulin or basiliximab for induction therapy. Incidences of acute rejection, antibody-treated acute rejection, delayed graft function, chronic rejection, cancer, infection, leucopenia, and thrombocytopenia were compared between thymoglobulin and basiliximab groups. Serum creatinine levels within 1 year and long-term graft and patient survival also were compared.

RESULTS

A total of 327 patients were included. Incidences of acute rejection, antibody-treated acute rejection, delayed graft function, and chronic rejection were significantly lower in the thymoglobulin group than in the basiliximab group (P < .05). Serum creatinine levels were lower in the thymoglobulin group on postoperative days 7, 14, and 30 (P < .05). There were no statistically significant differences regarding long-term graft and patient survival, cancer, or total infection rate between the groups. Incidences of Cytomegalovirus infection, leucopenia, and thrombocytopenia were significantly higher in the thymoglobulin group (P < .05).

CONCLUSIONS

Thymoglobulin may improve short-term outcomes, compared with basiliximab, in patients who had kidney transplants and are at high risk for acute rejection and delayed graft function. However, long-term outcomes are similar with thymoglobulin and basiliximab.

Association of pre-transplant statin use with delayed graft function in kidney transplant recipients

Background

Administration of HMG-CoA reductase inhibitors (statins), prior to ischemia or prior to reperfusion has been shown to decrease ischemia-reperfusion renal injury in animal studies. It is unknown whether this protective effect is applicable to renal transplantation in humans. The aim of this study was to determine the relationship between prior statin use in renal transplant recipients and the subsequent risk of delayed graft function.

Methods

All patients who underwent deceased or living donor renal transplantation at the Princess Alexandra Hospital between 1 July 2008 and 1 August 2010 were included in this retrospective, observational cohort study. Graft function was classified as immediate graft function (IGF), dialysis-requiring (D-DGF) and non-dialysis-requiring (ND-DGF) delayed graft function. The independent predictors of graft function were evaluated by multivariable logistic regression, adjusting for donor characteristics, recipient characteristics, HLA mismatch and ischaemic times.

Results

Overall, of the 266 renal transplant recipients, 21% exhibited D-DGF, 39% had ND-DGF and 40% had IGF. Statin use prior to renal transplantation was not significantly associated with the risk of D-DGF (adjusted odds ratio [OR] 1.05, 95% CI 0.96 – 1.15, P = 0.28). This finding was not altered when D-DGF and ND-DGF were pooled together (OR 0.98; 95% CI 0.89-1.06, p = 0.56).

Conclusions

The present study did not show a significant, independent association between prior statin use in kidney transplant recipients and the occurrence of delayed graft function.

Does delayed graft function in the first kidney transplant influence graft outcome in a subsequent transplant?

BACKGROUND

In kidney transplantation, delayed graft function (DGF) portends adverse graft and patient outcomes. It is unclear whether DGF in the first kidney transplant would adversely impact the outcome of a subsequent transplant.

METHODS

Utilizing data from the Organ Procurement and Transplant Network, we identified patients ≥ 18 years of age who underwent at least two deceased donor kidney transplantation (DDKT) between 1987 and 2010. Patients were then divided into two groups based on whether or not they developed DGF in the first transplant (1st TXP DGF group and 1st TXP no-DGF group). Unadjusted and adjusted graft survivals (Cox regression) between the groups were compared.

RESULTS

A total of 10,628 patients were identified who received more than one DDKT (3672 patients in the 1st TXP DGF group and 6956 patients in the 1st TXP no-DGF group). A higher incidence of DGF was observed with the second transplant in patients who had DGF in the first transplant (34% vs 26%, P = .001). Unadjusted graft survival for the second transplant was superior in the 1st TXP no-DGF group (P = .002). After correction for confounding variables, DGF in the first transplant did not have significant adverse impact on the graft survival of the second transplant (hazard ratio 1.2 with 95% confidence interval 0.96-1.09, P = .44).

CONCLUSIONS

In patients undergoing more than one DDKT, DGF in the first transplant is associated with higher incidence of DGF in the subsequent transplant but did not have independent adverse influence on the outcome of that graft.

Associations of pretransplant serum albumin with post-transplant outcomes in kidney transplant recipients

The association between pretransplant serum albumin concentration and post-transplant outcomes in kidney transplant recipients is unclear. We hypothesized that in transplant-waitlisted hemodialysis patients, lower serum albumin concentrations are associated with worse post-transplant outcomes. Linking the 5-year patient data of a large dialysis organization (DaVita) to the Scientific Registry of Transplant Recipients, we identified 8961 hemodialysis patients who underwent first kidney transplantation. Mortality or graft failure and delayed graft function (DGF) risks were estimated by Cox regression (hazard ratio [HR]) and logistic regression (Odds ratio [OR]), respectively. Patients were 48 ± 13 years old and included 37% women and 27% diabetics. The higher pretransplant serum albumin was associated with lower mortality, graft failure and DGF risk even after multivariate adjustment for case-mix, malnutrition-inflammation complex and transplant related variable. Every 0.2 g/dL higher pretransplant serum albumin concentration was associated with 13% lower all-cause mortality (HR = 0.87 [95% confidence interval: 0.82-0.93]), 17% lower cardiovascular mortality (HR = 0.83[0.74-0.93]), 7% lower combined risk of death or graft failure (HR = 0.93[0.89-0.97]) and 4% lower DGF risk (OR = 0.96[0.93-0.99]). Hence, lower pretransplant serum albumin level is associated with worse post-transplant outcomes. Clinical trials to examine interventions to improve nutritional status in transplant-waitlisted hemodialysis patients and their impacts on post-transplant outcomes are indicated.