Donation after cardiac death kidneys are suitable for pediatric recipients

A novel risk score for predicting prolonged length of stay following pediatric kidney transplant

BACKGROUND

Kidney transplants (KT) are accepted as the kidney replacement therapy of choice for children with kidney failure. The surgery itself may be more difficult especially in small children, and often leads to significant hospital stays. There is little research on predicting prolonged length of stay (LOS) in children. We aim to examine the factors associated with prolonged LOS following pediatric KT to help clinicians make informed decisions, better counsel families, and potentially reduce preventable causes of prolonged stay.

METHODS

We retrospectively analyzed the United Network for Organ Sharing database for all KT recipients less than 18 years old between January 2014 and July 2022 (n = 3693). Donor and recipient factors were tested in univariate and multivariate logistic analysis using stepwise elimination of non-significant factors to create a final regression model predicting LOS longer than 14 days. Values were assigned to significant factors to create risk scores for each individual patient.

RESULTS

In the final model, only primary diagnosis of focal segmental glomerulosclerosis, dialysis prior to KT, geographic region, and recipient weight prior to KT were significant predictors of LOS longer than 14 days. The C-statistic of the model is 0.7308. The C-statistic of the risk score is 0.7221.

CONCLUSIONS

Knowledge of the risk factors affecting prolonged LOS following pediatric KT can help identify patients at risk of increased resource use and potential hospital-acquired complications. Using our index, we identified some of these specific risk factors and created a risk score that can stratify pediatric recipients into low, medium, or high risk groups. A higher resolution version of the Graphical abstract is available as Supplementary information.

Delayed graft function in pediatric living donor kidney transplantation

BACKGROUND

Pediatric recipients of living donor kidneys have a low rate of delayed graft function (DGF). We examined the incidence, risk factors and outcomes of DGF in pediatric patients who received a living donor allograft.

METHODS

The STARfile was queried to examine all pediatric patients transplanted with a living donor kidney between 2000 and 2020. Donor and recipient demographic data were examined, as were survival and outcomes. Recipients were stratified into DGF and no DGF groups. DGF was defined as the need for dialysis within the first week after transplant.

RESULTS

6480 pediatric patients received a living donor (LD) kidney transplant during the study period. 269 (4.2%) developed DGF post-transplant. Donors were similar in age, creatinine, and cold ischemia time. Recipients of kidneys with DGF were similar in age, sensitization status and HLA mismatch. Focal segmental glomerulosclerosis (FSGS) was the most common diagnosis in recipients with DGF, and allograft thrombosis was the most common cause of graft loss in this group. Small recipients (weight < 15 kg) were found to have a significantly higher rate of DGF. Length of stay doubled in recipients with DGF, and rejection rates were higher post-transplant. Recipients of LD kidneys who developed DGF had significantly worse 1 year allograft survival (67% vs. 98%, p < .0001).

CONCLUSIONS

Pediatric living donor kidney transplant recipients who experience DGF have significantly poorer allograft survival. Optimizing the donor and recipient matching to avoid compounding risks may allow for better outcomes.

Use of DCD organs: Expanding the donor pool to increase pediatric transplantation

The number of children being listed for transplant continues to be greater than the number of available organs. In fact, over the past decade, rates of liver and kidney transplants in pediatric transplantation are essentially unchanged (Am J Transplant. 2020;20:193 and Am J Transplant. 2020;20:20). The use of DCD donors offers a potential solution to organ scarcity; however, the use of DCD organs in pediatric transplantation remains a rare event. Pediatric transplants done using carefully chosen DCD donor organs have shown to have outcomes similar to those seen with the use of donation after brain death (DBD) donors. Herein, we review the literature to examine the utilization of DCD livers and kidneys, outcomes of these allografts, and assess if DCD organs are a viable method to increase organ availability in pediatric transplantation.

Donation After Cardiac Death in Children

The wait list for organ transplant exceeds the rate of organ donation, especially in children. The solid-organ transplant rate has remained stable over time, despite increased demand. Although donation after cardiac death has helped to expand the donor organ pool for the adult population, this option remains scarce for children in need of transplant. Because long-term graft survival is more important in the pediatric group than in adults, we should reconsider the common notion that donation after cardiac death is inferior to donation after brain death. Herein, we review the literature to extract and analyze data regarding donation after cardiac death for solid-organ transplant in children.

Survival Benefit of Donation After Circulatory Death Kidney Transplantation in Children Compared With Remaining on the Waiting List for a Kidney Donated After Brain Death

BACKGROUND

Kidneys donated after circulatory death (DCD) are increasingly being used for transplantation in adults to alleviate organ shortage. Pediatric data on survival benefits of DCD transplantation compared with remaining on the waitlist for a kidney donated after brain death (DBD) offer are lacking.

METHODS

We used Scientific Registry of Transplant Recipients to identify 285 pediatric (<18 y) DCD kidney transplants performed between 1987 and 2017. Propensity score matching was used to create a comparison group of 1132 DBD transplants. We used sequential Cox analysis to evaluate survival benefit of DCD transplantation versus remaining on the waitlist and Cox regression to evaluate patient and graft survival.

RESULTS

DCD transplantation was associated with a higher incidence of delayed graft function (adjusted odds ratio: 3.0; P < 0.001). The risks of graft failure (adjusted hazard ratio [aHR], 0.89; P = 0.46) and death (aHR, 1.2; P = 0.67) were similar between DCD and DBD recipients. We found a significant survival benefit of DCD transplantation compared with remaining on the waitlist awaiting a DBD kidney (aHR, 0.44; P = 0.03).

CONCLUSIONS

Despite a higher incidence of delayed graft function, long-term patient and graft survival are similar between pediatric DCD and DBD kidney transplant recipients. DCD transplantation in children is associated with a survival benefit, despite pediatric priority for organ allocation, compared with remaining on the waitlist.

Considerations for utilizing medullary sponge kidney allografts in pediatric patients

BACKGROUND

Medullary sponge kidney (MSK) disease predisposes patients to recurrent nephrolithiasis, which affects one in every 5000 people in the United States.

METHODS

We report a rare case of a pediatric recipient of a living donor MSK transplant and discuss considerations when discussing risks and benefits of accepting MSK allografts for this population.

RESULTS

The recipient was admitted due to concerns for nephrolithiasis, hydronephrosis, and urinary tract infection at 1-month post-transplant. The hydronephrosis was resolved by surgical removal of an encrusted ureteral stent; this was followed by supplementation with oral medications to prevent future episodes of nephrolithiasis. The recipient did not have any further episodes after this as seen at a 1-year follow-up. The donor has remained well through this period.

CONCLUSIONS

With increasing organ shortages, the use of variety of donors may need to be considered to enlarge the organ pool.

Comparison of pediatric brain-dead donors to donation after circulatory death donors in the United States

In pediatrics, an increasing need for transplantable organs exists. This study aimed to describe the epidemiology of pediatric deceased donors in the United States. This retrospective observational study utilized data from the Organ Procurement and Transplantation Network (OPTN) from 2000 to 2015. Patients were stratified based on method of organ donation. Demographic variables and mechanism of death were then compared. A total of 14,481 deceased pediatric organ donors, donation after brain death (DBD) and donation after circulatory death (DCD), were included in the study, of which 8% were DCD donors. A significant difference (p<0.001) existed between the two donor groups with respect to ethnicity and mechanism of death. The annual trend of DCD and DBD donors showed an inverse relationship. During the 15-year study period the number of DBD donors decreased from 985 to 785 per year while DCD donors increased from 15 to 146 per year. As well, overall organs transplanted per year decreased from 3,475 to 3,117 over the 15-year study period. Significant differences exist between pediatric DBD donors and DCD donors, specifically with respect to ethnicity and mechanism of death. The number of pediatric DBD donors is decreasing while the number of pediatric DCD is slowly rising, making it increasingly important to be able to characterize these donors to better identify eligible DCD donors to optimize organ utilization.

Donor considerations in pediatric kidney transplantation

This article reviews kidney transplant donor options for children with end-stage kidney disease (ESKD). Global access to kidney transplantation is variable. Well-established national policies, organizations for organ procurement and allocation, and donor management policies may account for higher deceased donor (DD transplants) in some countries. Living donor kidney transplantation (LD) predominates in countries where organ donation has limited national priority. In addition, social, cultural, religious and medical factors play a major role in both LD and DD kidney transplant donation. Most children with ESKD receive adult-sized kidneys. The transplanted kidney has a finite survival and the expectation is that children who require renal replacement therapy from early childhood will probably have 2 or 3 kidney transplants in their lifetime. LD transplant provides better long-term graft survival and is a better option for children. When a living related donor is incompatible with the intended recipient, paired kidney exchange with a compatible unrelated donor may be considered. When the choice is a DD kidney, the decision-making process in accepting a donor offer requires careful consideration of donor history, kidney donor profile index, HLA matching, cold ischemia time, and recipient's time on the waiting list. Accepting or declining a DD offer in a timely manner can be challenging when there are undesirable facts in the donor's history which need to be balanced against prolonging dialysis in a child. An ongoing global challenge is the significant gap between organ supply and demand, which has increased the need to improve organ preservation techniques and awareness for organ donation.