Fate of the mate: the influence of delayed graft function in renal transplantation on the mate recipient

Understanding Delayed Graft Function to Improve Organ Utilization and Patient Outcomes: Report of a Scientific Workshop Sponsored by the National Kidney Foundation

Delayed graft function (DGF) is a common complication after kidney transplant. Despite extensive literature on the topic, the extant definition of DGF has not been conducive to advancing the scientific understanding of the influences and mechanisms contributing to its onset, duration, resolution, or long-term prognostic implications. In 2022, the National Kidney Foundation sponsored a multidisciplinary scientific workshop to comprehensively review the current state of knowledge about the diagnosis, therapy, and management of DGF and conducted a survey of relevant stakeholders on topics of clinical and regulatory interest. In this Special Report, we propose and defend a novel taxonomy for the clinical and research definitions of DGF, address key regulatory and clinical practice issues surrounding DGF, review the current state of therapies to reduce and/or attenuate DGF, offer considerations for clinical practice related to the outpatient management of DGF, and outline a prospective research and policy agenda.

Quantifying Donor Effects on Transplant Outcomes Using Kidney Pairs from Deceased Donors

BACKGROUND AND OBJECTIVES

In kidney transplantation, the relative contribution of donor versus other factors on clinical outcomes is unknown. We sought to quantify overall donor effects on transplant outcomes for kidney donations from deceased donors.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

For paired donations from deceased donors resulting in transplants to different recipients, the magnitude of donor effects can be quantified by examining the excess of concordant outcomes within kidney pairs beyond chance concordance. Using data from the Organ Procurement and Transplantation Network between the years 2013 and 2017, we examined concordance measures for delayed graft function, death-censored 1-year graft failure, and death-censored 3-year graft failure. The concordance measures were excess relative risk, excess absolute risk, and the fixation index (where zero is no concordance and one is perfect concordance). We further examined concordance in strata of kidneys with similar values of the Kidney Donor Profile Index, a common metric of organ quality.

RESULTS

If the transplant of the kidney mate resulted in delayed graft function, risk for delayed graft function was 19% higher (95% confidence interval [95% CI], 18% to 20%), or 1.76-fold higher (95% CI, 1.73- to 1.80-fold), than baseline. If a kidney graft failed within 1 year, then the kidney mate's risk of failure was 6% higher (95% CI, 4% to 9%), or 2.85-fold higher (95% CI, 2.25- to 3.48-fold), than baseline. For 3-year graft failure, the excess absolute risk was 7% (95% CI, 4% to 10%) but excess relative risk was smaller, 1.91-fold (95% CI, 1.56- to 2.28-fold). Fixation indices were 0.25 for delayed graft function (95% CI, 0.24 to 0.27), 0.07 for 1-year graft failure (95% CI, 0.04 to 0.09), and 0.07 for 3-year graft failure (95% CI, 0.04 to 0.10). Results were similar in strata of kidneys with a similar Kidney Donor Profile Index.

CONCLUSIONS

Overall results indicated that the donor constitution has small or moderate effect on post-transplant clinical outcomes.

Donor kidney injury molecule-1 promotes graft recovery by regulating systemic necroinflammation

Ischemia-reperfusion injury during kidney transplantation predisposes to delayed graft function, rejection, and premature graft failure. Exacerbation of tissue damage and alloimmune responses may be explained by necroinflammation: an autoamplification loop of cell death and inflammation, which is mediated by the release of damage-associated molecular patterns (eg, high-mobility group box-1; HMGB1) from necrotic cells that activate both innate and adaptive immune pathways. Kidney injury molecule-1 (KIM-1) is a phosphatidylserine receptor that is upregulated on injured proximal tubular epithelial cells and enables them to clear apoptotic and necrotic cells. Here we show a pivotal role for clearance of dying cells in regulating necroinflammation in a syngeneic murine kidney transplant model. We found persistent KIM-1 expression in KIM-1^+/+ kidney grafts posttransplantation. Compared to recipients of KIM-1^+/+ kidneys, recipients of KIM-1^-/- kidneys exhibited significantly more renal dysfunction, apoptosis and necrosis, tubular obstruction, and graft failure. KIM-1^-/- grafts also had more inflammatory cytokines, infiltrating neutrophils, and macrophages compared to KIM-1^+/+ grafts. Most significantly, passive release of HMGB1 from apoptotic and necrotic cells led to dramatically higher serum HMGB1 levels and increased proinflammatory macrophages in recipients of KIM-1^-/- grafts. Our data identify an endogenous protective mechanism against necroinflammation in kidney grafts that may be of therapeutic relevance in transplantation.

Concordance of outcomes of pairs of kidneys transplanted into different recipients

Kidney transplant outcomes are influenced by donor characteristics, including age and gender. Additional donor factors, both genetic and environmental, also influence graft outcome. We aim to assess the strength of donor factors in determining kidney transplant outcomes by comparing paired kidneys from a single donor transplanted into different recipients. We conducted a retrospective cohort study of outcomes of pairs of deceased donor kidneys transplanted in our centre between 1992 and 2008. We examined the relationship within pairs for eGFR at 1 year and at 5 years post-transplant using Spearman's Correlation and the concordance of pairs of transplant kidneys with respect to the occurrence of acute rejection and delayed graft function (DGF). A total of 652 recipient pairs were analysed. Spearman's correlation for eGFR was 0.36 at 1 year and 0.36 at 5 years post-transplant. The incidence of DGF was 11%. The odds ratio of DGF occurring if the contralateral kidney had DGF was 5.99 (95% CI, 3.19-11.25). There is a significant degree of relationship within pairs of kidneys transplanted from the same donor for serum creatinine at 1 year and 5 years post-transplant and also for the occurrence of delayed graft function.

Recipient and donor body mass index as important risk factors for delayed kidney graft function

BACKGROUND

Obesity is increasingly impacting the overall health status and the global costs for health care. The increase in body mass index (BMI) is also observed in kidney allograft recipients and deceased organ donors.

METHODS

In a retrospective single-center study, we analyzed 1132 deceased donor kidney grafts, transplanted at our institution between 2000 and 2009 for recipient and donor BMI and its correlation with delayed graft function (DGF). Recipients/donors were classified according to their BMI (<18.5, 18.5-24.9, 25-29.9, and >30 kg/m(2)). DGF was defined as requirement for one dialysis within the first week after transplantation.

RESULTS

Overall DGF rate was 32.4%, mean recipient BMI was 23.64 ± 3.75 kg/m(2), and mean donor BMI was 24.69 ± 3.44 kg/m(2). DGF rate was 25.2%, 29.8%, 40.9%, and 52.6% in recipients with BMI less than 18.5, 18.5 to 24.9, 25 to 29.9, and more than 30 kg/m, respectively (P<0.0001). Donor BMI less than 18.5, 18.5 to 24.9, 25 to 29.9, more than 30 kg/m(2) resulted in a DGF rate of 22.5%, 31.0%, 37.3%, and 51.2% (P < 0.0001). Multivariate analysis revealed recipient BMI and dialysis duration as independent risk factors for DGF. DGF results in inferior 1- and 5-year graft and patient survival.

CONCLUSION

Recipient and donor BMI correlate with the incidence of DGF. Awareness thereof should have an impact on peri- and posttransplant measures in renal transplant recipients.

Risk factors and outcome of delayed graft function after cadaveric kidney transplantation: a report from the Thai Transplant Registry

INTRODUCTION

Kidney transplantation is the best treatment for end-stage renal disease patients. Delayed graft function (DGF) remains one of the major problems after cadaveric kidney transplantation. This study has reported the risk factors and outcomes of DGF using data from Thai Transplant Registry Database.

METHODS

The data of all cadaveric kidney transplantations (CD-KT) were retrieved from the database. DGF was defined as a failure to decrease the serum creatinine within 72 hours or a requirement for dialysis within the first week after transplantation. We performed logistic regression analysis to correlate donor features (age, sex, cardio-pulmonary resuscitation (CPR), brain death from a cerebrovascular accident (CVA), best and last serum creatinine) with recipient demographics (age, sex) and clinical outcomes cold ischemic time [CIT] and DGF.

RESULTS

We analyzed 756 CD-KT including 320 (42%) patients experiencing DGF. Upon multivariate analysis, factors significantly correlated with DGF were CIT (P < .001), donor last serum creatinine (P < .001), interleukin 2 monoclonal antibody induction (P = .004), donor age (P = .017), donor CVA (P = .012), and prior peritoneal dialysis (PD) (P = .012). There was no significant correlation between DGF and donor height, weight, sex, CPR, brain death from CVA, best serum creatinine, recipient age, or sex in multivariate analysis. Graft survivals at 1 and 5 years after transplantation were significantly lower among the DGF group namely, 91.0% vs. 95.2% and 78.7% vs. 86.0%, respectively (P = .006). Patient survival was also significantly lower 94.1% vs. 96.4% and 82.1% vs. 92.2%, respectively, (P = .001).

CONCLUSION

A higher value of the donor's terminal serum creatinine, CIT, IL2mAb induction, PD prior to KT and donor age increased the risk for DGF after CD-KT. DGF significantly lowered kidney allograft and patient survivals at 1 and 5 years after transplantation among the Thai population.