Preoperative Risk Assessment of Early Kidney Graft Loss.

Background: A large proportion of potential organ donors are not utilized for kidney transplantation out of risk of early allograft loss because of donor-related characteristics. These can be summarized using kidney donor profile index (KDPI). Because KDPI affects the choice of the recipient, the predictive ability of KDPI is tied to recipient attributes. These have been questioned to explain most of the predictive ability of KDPI. This study aims to quantify the effect of the donor on early graft loss (EGL) by accounting for nonrandom allocation. Methods: This study included patients undergoing kidney transplantation from deceased donors between 2014 and 2020 from the Scientific Registry of Transplantation Recipients. EGL, defined as a return to dialysis or retransplantation during the first posttransplant year, was the primary endpoint. Nonrandom allocation and donor-recipient matching by KDPI necessitated the use of inverse probability treatment weighting, which served to assess the effect of KDPI and mitigate selection bias in a weighted Cox regression model. Results: The study comprised 89 290 transplantations in 88 720 individual patients. Inverse probability treatment weighting resulted in a good balance of recipient covariates across values of continuous KDPI. Weighted analysis showed KDPI to be a significant predictor for short-term outcomes. A comparable (in terms of age, time on dialysis, previous transplants, gender, diabetes status, computed panel-reactive antibodies, and HLA mismatches) average recipient, receiving a kidney from a donor with KDPI 40-60 had a 3.5% risk of EGL increased to a risk of 7.5% if received a kidney from a KDPI >95 donor (hazard ratio, 2.3; 95% confidence interval, 1.9-2.7). However, for all-cause survival KDPI was less influential. Conclusions: The predictive ability of KDPI does not stem from recipient confounding alone. In this large sample-sized study, modeling methods accounting for nonindependence of recipient selection verify graft quality to effectively predict short-term transplantation outcomes.

Characteristics of Delayed Graft Function and Long-Term Outcomes After Kidney Transplantation From Brain-Dead Donors: A Single-Center and Multicenter Registry-Based Retrospective Study.

Delayed graft function (DGF) after kidney transplantation is common and associated with worse graft outcomes. However, little is known about factors affecting graft survival post-DGF. We studied the association of cold ischemia time (CIT) and Kidney Donor Profile Index (KDPI) with the long-term outcomes of deceased brain-dead donor kidneys with and without DGF. Data from Finland (n = 2,637) and from the US Scientific Registry of Transplant Recipients (SRTR) registry (n = 61,405) was used. The association of KDPI and CIT with the graft survival of kidneys with or without DGF was studied using multivariable models. 849 (32%) kidneys had DGF in the Finnish cohort. DGF and KDPI were independent risk factors for graft loss, [HR 1.32 (95% CI 1.14-1.53), p < 0.001, and HR 1.01 per one point (95% CI 1.01-1.01), p < 0.001, respectively], but CIT was not, [HR 1.00 per CIT hour (95% CI 0.99-1.02), p = 0.84]. The association of DGF remained similar regardless of CIT and KDPI. The US cohort had similar results, but the association of DGF was stronger with higher KDPI. In conclusion, DGF and KDPI, but not CIT, are independently associated with graft survival. The association of DGF with worse graft survival is consistent across different CITs but stronger among marginal donors.

Risk and prediction of kidney failure early after liver transplantation.

BACKGROUND: Kidney disease is common after liver transplantation (LT), but postoperative kidney failure is difficult to predict. Current guidelines recommend simultaneous liver-kidney transplantation (SLKT) in patients with pre-LT estimated glomerular filtration rate (eGFR) below 30-40 mL/min, which might be too liberal. The aim of this study was to evaluate the risk of kidney failure after LT. We also assessed the predictive ability of pretransplantation eGFR using various equations. METHODS: This single-center study included patients undergoing primary LT 2006-2020. Patients undergoing simultaneous liver-kidney transplantations or on dialysis before LT were analysed separately. We calculated 5 different eGFR equations measured just before LT and assessed their predictive ability using Kaplan-Meier cumulative incidence estimates. RESULTS: Among 556 LT patients with a median follow-up of 5.0 years (IQR 2.0-8.5), 20 developed kidney failure during follow-up, 7 of them within 1-year post LT. Six of these 7 suffered from major perioperative complications. Depending on the eGFR equation used, the incidence of kidney failure within 1-year was 3.9-6.7% at pre-LT eGFR-values <30 mL/min, 1.2-3.1% at eGFR 30-60 mL/min, and 0.6-0.9% at eGFR >60 mL/min. CONCLUSIONS: Kidney failure within 1-year post-LT could not be reliably predicted by pre-LT eGFR. However, kidney failure was uncommon even in patients with severely reduced pre-LT glomerular filtration rate (eGFR <30 mL/min), and extremely rare in patients unaffected by major perioperative complications. Our data prompts further consideration regarding the guidelines for SLKT in patients with a reduced preoperative eGFR.

Association of Procurement Time With Pancreas Transplant Outcomes in Brain-Dead Donors.

A brain-death-induced cytokine storm damages organs in an organ donor. However, a longer time period between declaration of brain death and organ procurement (procurement interval) is associated with improved outcomes in kidney, liver, heart, and lung transplantation. The aim of this study was to find the optimal procurement interval for pancreas transplantation. Association of procurement interval with pancreas graft outcomes was analyzed using multivariable models adjusted for variables possibly affecting procurement interval and outcomes. Altogether 10,119 pancreas transplantations were included from the Scientific Registry of Transplant Recipients. The median follow-up was 3.2 (IQR 1.01-6.50) years. During the first year, 832 (9.0%) grafts were lost, including 555 (6.0%) within the first 30 days. Longer procurement interval was associated with increased death-censored graft survival in a multivariable model (HR 0.944 95% CI 0.917-0.972, per 10-h increase, p < 0.001). A decreasing hazard of graft loss was observed also with 1-year, but not with 30-day graft survival. During 1-year follow-up, 953 (12.1%) patients had an acute rejection, and longer procurement interval was also associated with less acute rejections (OR 0.937 95% CI 0.900-0.976, per 10-h increase, p = 0.002) in the multivariable model. In conclusion, longer procurement interval is associated with improved long-term outcomes in pancreas transplantation.

Timing of Organ Procurement From Brain-Dead Donors Associates With Short- and Long-Term Outcomes After Liver Transplantation.

Brain death-induced cytokine storm is thought to harm transplantable organs. However, longer procurement times have been associated with non-inferior or better outcomes in kidney, heart, and lung transplants, while optimal procurement time for liver allografts is unknown. Our aim was to analyze the association of time interval from brain death to organ procurement with liver allograft outcomes in two nationwide cohorts. The association of procurement interval with graft survival and short-term complications was analysed in multivariable models. Altogether 643 and 58,017 orthotopic liver transplantations from brain-dead donors were included from Finland between June 2004 and December 2017 and the US between January 2008 and August 2018, respectively. Median time from brain death to organ procurement was 10.5 h in Finland and 34.6 h in the US. Longer interval associated with better graft survival (non-linearly, p = 0.016) and less acute rejections (OR 0.935 95% CI 0.894-0.978) in the US cohort, and better early allograft function (p = 0.005; Beta -0.048 95% CI -0.085 -(-0.011)) in the Finnish cohort, in multivariable models adjusted with Donor Risk Index, recipient age, Model for End-Stage Liver Disease and indication for transplantation. Progressive liver injury after brain death is unlikely. Rushing to recover seems unnecessary; rest and repair might prove beneficial.

The Association of Time to Organ Procurement on Short- and Long-Term Outcomes in Kidney Transplantation.

BACKGROUND AND OBJECTIVES: Transplant centers in Europe aim to minimize the time from brain death to organ procurement (procurement delay), but evidence to justify this is scarce. In the United States, procurement times are significantly longer. Our objective was to analyze how procurement delay associates with kidney allograft outcomes. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Kidney transplantations from brain-dead donors were retrospectively analyzed from the Finnish Kidney Transplant Registry and the Scientific Registry of Transplant Recipients in the United States. Multivariable models were adjusted with donor and recipient characteristics, and the relationship between procurement delay and outcomes was modeled with cubic spline functions. RESULTS: In total, 2388 and 101,474 kidney transplantations in Finland and the United States were included, respectively. The median procurement delay was 9.8 hours (interquartile range, 7.8-12.4) in Finland and 34.8 hours (interquartile range, 26.3-46.3) in the United States. A nonlinear association was observed between procurement delay and the risk of delayed graft function, with highest risk seen in short and very long procurement delays. In multivariable models, the lowest risk of delayed graft function was associated with procurement delay between 20 and 50 hours. In multivariable models, longer procurement delay was linearly associated with lower risk of graft loss (hazard ratio, 0.90/1 h longer; 95% confidence interval, 0.88 to 0.92; P<0.001). Acute rejection rates, for which data were only available from Finland, were not associated with procurement delay. CONCLUSIONS: Longer procurement delay was associated with noninferior or even better kidney allograft outcomes.