Does donor kidney to recipient body weight ratio influence long-term outcomes of living-donor kidney transplantation?

Dominant predictors of early post-transplant outcomes based on the Korean Organ Transplantation Registry (KOTRY)

Data for Asian kidney transplants are very limited. We investigated the relative importance of prognostic markers in Asian kidney transplants by using Korean Organ Transplantation Registry (KOTRY) cohort. Prediction models were developed by data-driven variable selection approach. The relative importance of the selected predictors was measured by dominance analysis. A total of 4854 kidney transplant donor-recipient pairs were analyzed. Overall patient survival rates were 99.8%, 98.8%, and 91.8% at 1, 3, and 5 years, respectively. Death-censored graft survival rates were 98.4%, 97.0%, and 95.8% at 1, 3, and 5 years. Biopsy-proven acute rejection free survival rates were 90.1%, 87.4%, and 87.03% at 1, 3, and 5 years. The top 3 dominant predictors for recipient mortality within 1 year were recipient cardiovascular disease history, deceased donor, and recipient age. The dominant predictors for death-censored graft loss within 1 year were acute rejection, deceased donor, and desensitization. The dominant predictors to acute rejection within 1 year were donor age, HLA mismatched numbers, and desensitization. We presented clinical characteristics of patients enrolled in KOTRY during the last 5 years and investigated dominant predictors for early post-transplant outcomes, which would be useful for clinical decision-making based on quantitative measures.

Assessing donor-recipient size metrics for heart transplant outcomes: UNOS database analysis

STUDY

There is no widely accepted donor to recipient size-match metric to predict outcomes in cardiac transplant. The predictive ability of size-match metrics has not been studied when recipients are stratified by heart failure etiology. We sought to assess the performance of commonly used size metrics to predict survival after heart transplant, accounting for restrictive vs. non-restrictive pathology.

METHODS

The UNOS registry was queried from 2000-2017 for all primary isolated heart transplants. Donor-recipient ratios were calculated for commonly used size metrics and their association with survival was assessed using continuous, nonlinear analysis.

RESULTS

29,817 patients were identified. Height (p<0.001), predicted heart mass (PHM) (p = 0.003), ideal body weight (IBW) (p<0.001) and body mass index (BMI) (p = 0.003) ratios were significantly associated with survival, while weight and body surface area (BSA) ratios were not. When stratified, only BMI ratio retained significance for both restrictive (p = 0.051) and non-restrictive (p = 0.003) subsets. Recipients with restrictive etiology had increased risk of mortality with both a lower and higher BMI ratio.

CONCLUSIONS

While many metrics show association with survival in the non-restrictive subset, BMI is the only metric that retains significance in the restrictive subset. Recipients with restrictive and non-restrictive etiologies of heart failure tolerate size mismatch differently. This article is protected by copyright. All rights reserved.

Donor kidney volume measured by computed tomography is a strong predictor of recipient eGFR in living donor kidney transplantation

PURPOSE

The effect of living donor kidney allograft size on recipient outcomes is not well understood. In this study, we sought to investigate the relationship between preoperatively measured donor kidney volume and recipient estimated glomerular filtration rate (eGFR) in living donor kidney transplantation (LDKT).

METHODS

We studied computed tomography (CT) donor kidney volumes and recipient outcomes for 438 LDKTs at the Toronto General Hospital between 2007 and 2016. Estimated glomerular filtration rate (eGFR) was calculated at 1, 3, and 6 months and a multivariable linear regression model was fitted to study the effect of donor kidney volume on recipient eGFR.

RESULTS

The mean volume and weight of the donated kidneys were 157.3 (± 32.3) cc and 186.7 (± 48.7) g, respectively. Kidney volume was significantly associated with eGFR on multivariable analysis (P < 0.001). Specifically, for every 10 cc increase in kidney volume, there was a 1.68 mL/min, 1.25 mL/min and 0.97 mL/min rise in recipient eGFR at 1, 3, and 6 months, respectively.

CONCLUSIONS

Donor kidney volume is a strong independent predictor of recipient eGFR in LDKT, and therefore, may be a valuable addition to predictive models of eGFR after transplant. Further research may determine if the inclusion of donor kidney volume in matching algorithms can improve recipient outcomes.

Impact of Kidney Graft Weight-to-Recipient Body Weight Ratio on Long-Term Graft Function in Living Donor Kidney Transplant

OBJECTIVES

Our objective was to evaluate the effect of kidney graft weight-to-recipient body weight ratio as a nonimmune factor that may affect long-term graft function.

MATERIALS AND METHODS

We retrospectively collected data from 2531 living donor kidney transplant procedures performed between 1994 and 2010 at Shahid Labbafinejad Medical Center; 635 patients were included in this study. Each kidney was weighed after cold wash. The kidney weight-to-recipient body weight ratio was calculated. As an indicator of graft function, we used the Modification of Diet in Renal Disease Study Group equation to estimate glomerular filtration rate. For statistical analyses, we used simple linear regression analysis and the mixed model test using SPSS version 17.0 software (SPSS, Chicago, IL, USA).

RESULTS

Mean age of recipients and median follow-up duration were 37.5 years (range, 6-77 y) and 36 months (range, 25-84 mo). Long-term graft function showed a positive correlation with kidney graft-to-recipient body weight ratio but not with the graft weight alone. The magnitude of this correlation was higher early after surgery (day 7) and decreased with long-term follow-up but was still statistically significant (P < .001).

CONCLUSIONS

From our results, we conclude that kidney graft-to-recipient body weight ratio is correlated with the kidney graft function; graft size matching may be considered for kidney donor selection.

Influence of Various Living Donor Kidney Measurements in Relation to Recipient Body Measurements on Posttransplant Allograft Functional Outcomes

OBJECTIVES

Donor kidney measurements may affect outcomes of transplanted allografts. We tested allograft and recipient measurements on kidney allograft outcomes. In this study, we compared the effects of kidney allograft volumes, which were measured using computed tomographic angiography before transplant, and allograft weight, which was measured during surgery, in relation to the recipient's body weight and body mass index on kidney function at 6 and 12 months after transplant.

MATERIAL AND METHODS

We included 74 patients (40 female and 34 male patients, mean age of 50.42 ± 9.75 y) in this study.

RESULTS

Intraoperative allograft weight was 182.68 ± 40.33 g (range, 104-266 g). The allograft volume measured using computed tomographic angiography scanning was 123.34 ± 24.26 mL (range, 78-181 mL). The estimated glomerular filtration rates of the recipients at 6 and 12 months after transplant correlated negatively with age and recipient body mass index but correlated positively with allograft volume/recipient body weight, allograft volume/recipient body mass index, allograft weight, allograft weight/recipient body weight, and allograft weight/recipient body mass index values, as concluded by univariate analyses. From multivariate analyses, we found variables of interest presumed to significantly affect the 12-month estimated glomerular filtration rates, including recipient age, allograft volume/recipient body weight, allograft volume/recipient body mass index, allograft weight, allograft weight/recipient body weight, and allograft weight/recipient body mass index.

CONCLUSIONS

Transplanted allograft and recipient body values may be used as predictors of estimated glomerular filtration rates 6 and 12 months after transplant.

The Outcomes of Living Kidney Donation from Medically Complex Donors: Implications for the Donor and the Recipient

Living kidney donation is an important option for patients with end-stage renal disease (ESRD), and has improved life expectancy and quality for patients otherwise requiring maintenance dialysis or deceased-donor transplantation. Given the favorable outcomes of live donation and the shortage of organs to transplant, individuals with potentially unfavorable demographic and clinical characteristics are increasingly being permitted to donate kidneys. While this trend has successfully expanded the live donor pool, it has raised concerns as to which acceptance criteria are safe. This review aims to summarize the existing literature on the outcomes of transplantation from medically complex, living kidney donors, including both donor and recipient outcomes when available.

Pseudorejection and true rejection after kidney transplantation: classification and clinical significance

OBJECTIVES

Multiple factors may result in an elevation in serum creatinine level after kidney transplantation, mimicking rejection. It is crucial to differentiate between a true rejection and other conditions inducing a 'pseudorejection', in order to avoid overtreatment, or worse, mistreatment. Our goal was to review and classify true rejections and pseudorejections and their clinical significance.

MATERIAL AND METHODS

This was a retrospective review of articles published in the USA and Europe, from 1976 to the present. The sites from which information was retrieved included PubMed, Clinical Imaging, Histopathology, Archives of Surgery, JACS, the American Urological Association, Medline and Springer Link. The importance of the resistive index will also be emphasized.

RESULTS

We reviewed 61 articles regarding the causes of renal graft dysfunction, which may be classified into true rejections and pseudorejections, the latter including the following 6 factors: hyperglycemia, ureteral obstruction, lymphocele, arterial stenosis, infection and recurrence of primary pathology.

CONCLUSIONS

'Pseudorejection' has been described only once, for the first time in 1976 in the USA, and there have been no other reports since then. Multiple factors, mainly hyperglycemia, may induce a pseudorejection, presenting with an elevation of serum creatinine level and leading the clinician to an erroneous diagnosis of true rejection initially, resulting in inappropriate management.