Mariana C. Chiles

The weekend effect alters the procurement and discard rates of deceased donor kidneys in the United States

Factors contributing to the high rate of discard among deceased donor kidneys remain poorly understood and the influence of resource limitations of weekends on kidney transplantation is unknown. To quantify this we used data from the Scientific Registry of Transplant Recipients and assembled a retrospective cohort of 181,799 deceased donor kidneys recovered for transplantation from 2000-2013. We identified the impact of the day of the week on the procurement and subsequent utilization or discard of deceased donor kidneys in the United States, as well as report the geographic variation of the impact of weekends on transplantation. Compared with weekday kidneys, organs procured on weekends were significantly more likely to be discarded than transplanted (odds ratio: 1.16; 95% confidence interval: 1.13-1.19), even after adjusting for organ quality (adjusted odds ratio: 1.13; 95% confidence interval: 1.10-1.17). Weekend discards were of a significantly higher quality than weekday discards (Kidney Donor Profile Index: 76.5% vs. 77.3%). Considerable geographic variation was noted in the proportion of transplants that occurred over the weekend. Kidneys available for transplant over the weekend were significantly more likely to be used at larger transplant centers, be shared without payback, and experienced shorter cold ischemia times. Thus, factors other than kidney quality are contributing to the discard of deceased donor kidneys, particularly during weekends. Policy prescriptions, administrative or organizational solutions within transplant programs may potentially mitigate against the recent increase in kidney discards.

Association between Reperfusion Renal Allograft Biopsy Findings and Transplant Outcomes

Biopsy findings at the time of procurement of deceased donor kidneys remain the most common reason cited for kidney discard. To determine the value of renal allograft histology in predicting outcomes, we evaluated the significance of histologic findings, read by experienced renal pathologists, in 975 postreperfusion biopsy specimens collected from 2005 to 2009 after living donor (n=427) or deceased donor (n=548) renal transplant. We evaluated specimens for the degree of glomerulosclerosis, interstitial fibrosis and tubular atrophy, and vascular disease; specimens with a score of 0 or 1 (scale, 0-3) for each parameter were considered optimal. Overall, 66.3% of living donor kidneys and 50.7% of deceased donor kidneys received an optimal histology score (P<0.001). Irrespective of donor status, suboptimal kidneys came from older donors with a higher incidence of diabetes mellitus, hypertension, and obesity and a higher mean kidney donor risk index (all P<0.001). Death-censored outcomes after transplant differed significantly between optimal and suboptimal kidneys only in the deceased donor transplants (P=0.02). Regardless of histologic classification, outcomes with deceased donor kidneys were inferior to outcomes with living donor kidneys. However, 73.2% of deceased donor kidneys with suboptimal histology remained functional at 5 years. Our findings suggest that histologic findings on postreperfusion biopsy associate with outcomes after deceased donor but not living donor renal transplants, thus donor death and organ preservation-related factors may be of greater prognostic importance. Discarding donated kidneys on the basis of histologic factors may be inappropriate and merits further study.

Achieving Equity through Reducing Variability in Accepting Deceased Donor Kidney Offers

In this issue of the Clinical Journal of the American Society of Nephrology , Huml et al. ([1][1]) report an important analysis of the outcomes for all offers of deceased donor kidneys to transplant centers in the United States over a 5-year period. From May of 2007 to July of 2012, over 7 million

Predictive Value of Using Initial Versus Terminal Deceased Donor Creatinine to Calculate the Kidney Donor Risk Index

To the Editors: Implementation of the Kidney Allocation System (KAS) for deceased donor kidneys (DDKs) in the United States was intended to optimize kidney allocation, reduce disparities, and increase organ utilization. KAS incorporates the Kidney Donor Risk Index (KDRI), an estimate of the relative risk for transplant failure of a donor’s kidney versus the median donor. The KDRI (also expressible as a percentile score, the Kidney Donor Profile Index [KDPI]), is calculated using 10 donor-specific characteristics, thus de-emphasizing any single characteristic during the organ acceptance process. In the setting of donor acute kidney injury (AKI) prior to procurement, use of the terminal serum creatinine (Scrt) for calculating KDRI/KDPI may result in a higher value than that computed using the initial Scr (Scri). 3 The presence of AKI increases the risk for organ discard despite evidence suggesting excellent outcomes associated with these kidneys. Using data from the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) Standard Transplant Analysis and Research (STAR) file, we conducted a retrospective cohort study to examine the relationship between donor Scri and Scrt and their impact on KDRI/KDPI scores. Scri values were obtained from OPTN/UNOS and linked to the STAR file, which contains Scrt. To denote KDRI calculated with Scri and Scrt, we use KDRIi and KDRIt, respectively. From 2000 to 2015 we identified 236,385 DDKs, of which 212,926 were procured for transplantation (Item S1). After excluding kidneys from donors with missing Scri and Scrt values (n 5 83,908), kidneys with either Scr . 40 mg/dL (n 5 31), and kidneys with both Scr values

Relation of Coronary Flow Reserve to Other Findings on Positron Emission Tomography Myocardial Perfusion Imaging and Left Heart Catheterization in Patients With End-stage Renal Disease Being Evaluated for Kidney Transplant

8 mg/dL (n 5 4), we identified 128,983 organs.

Association between the “Timed Up and Go Test” at transplant evaluation and outcomes after kidney transplantation: XXXX

Cardiovascular disease is the leading cause of death in patients with end-stage renal disease (ESRD) and often goes undetected. Abnormal coronary flow reserve (CFR), which predicts increased risk of cardiac death, may be present in patients with ESRD without other evidence of coronary artery disease (CAD). We prospectively studied 131 patients who had rest and dipyridamole pharmacologic stress N13-ammonia positron emission tomography myocardial perfusion imaging (PET MPI) for kidney transplant evaluation. Thirty-four patients also had left heart catheterization. Abnormal PET MPI was defined as qualitative ischemia or infarct, stress electrocardiogram ischemia, or transient ischemic dilation. CFR was calculated as the ratio of stress to rest coronary blood flow. Global CFR < 2 was defined as abnormal. Of 131 patients who had PET MPI (66% male, 55.6 ± 12.1 years), 30% (39 of 131) had abnormal PET MPI and 59% (77 of 131) had abnormal CFR. In a subset of 34 patients who had left heart catheterization (66% male, 61.0 ± 12.1 years), 68% (23 of 34) had abnormal CFR on PET MPI, and 68% (23 of 34) had ≥70% obstruction on left heart catheterization. Abnormal CFR was not significantly associated with abnormal PET MPI (p = 0.13) or obstructive CAD on left heart catheterization (p = 0.26). In conclusion, in the first prospective study of PET MPI in patients with ESRD, abnormal CFR is highly prevalent and is independent of abnormal findings on PET MPI or obstructive CAD on left heart catheterization.

Outcomes for Potential Kidney Transplant Recipients Offered Public Health Service Increased Risk Kidneys: A Single Center Experience

Studies have demonstrated the Timed Up and Go Tests (TUGT) ability to forecast postoperative outcomes for several surgical specialties. Evaluations of the TUGT for waitlist and posttransplant outcomes have yet to be examined in kidney transplantation.

Factors leading to the discard of deceased donor kidneys in the United States

Discard rate of Public Health Service Increased Risk (PHS‐IR) organs is high despite the absence of worse kidney transplant outcomes.