Time to second kidney transplantation in young adults after failed pediatric kidney transplant

Abstract

Background: Under the current kidney allocation system, pediatric candidates listed prior to age 18 receive priority for high-quality deceased donor organs. This has resulted in a decline in living donor transplantation in pediatrics, despite superior outcomes of living donor transplantation. Due to a young age at transplantation, most pediatric kidney transplant recipients require re-transplantation. The effects of a previously failed deceased donor vs a previously failed living donor on re-transplant candidates are unknown. Methods: Using the United Network for Organ Sharing database, we examined 2772 re-transplant recipients aged 18-30 years at time of relisting for second KT from 2000 to 2018 with history of prior pediatric KT (age ≤ 18 years). Results: PFLDKT recipients compared to those with PFDDKT had shorter median waiting times and dialysis time regardless of their second donor type (14.0 vs 20.3 months, and 19.1 vs 34.5 months, respectively). PFLDKT recipients had higher re-transplant rates (adjusted HR 1.17, 95% CI 1.09-1.27, and adjusted HR 1.05, 95% CI 0.95-1.15 when calculating from time of relisting and time of returning to dialysis, respectively). PFDDKT recipients were more likely to have higher median PRA levels (90% vs 73%). Conclusions: Re-transplant candidates who received a previous deceased donor as a child had a higher level of sensitization, longer waiting time, and dialysis exposure compared to those with PFLDKT. Among primary pediatric kidney transplant candidates, consideration should be considered for living donor transplantation, despite the priority for deceased donor organs, to avoid increased sensitization and longer waiting times for with re-transplantation.

Optimal Sequencing of Deceased Donor and Live Donor Kidney Transplant Among Pediatric Patients With Kidney Failure

“… 10 , 11 Studies also show greater sensitization and lower rates of transplant in patients who undergo transplant with a DD kidney first compared with an LD kidney first, which further supports an LD-first sequence. 10 , 11 Delays may be unavoidable (eg, precipitous graft loss, delay in LD workup or finding a new LD). For recipients who have developed HLA antibodies to their LD transplant, entering a paired exchange registry or desensitization are options.…”

“… 12 Individuals with reduced access to transplant, live donation, or preemptive listing will have worse outcomes in both sequences. 11 We did not reduce transplant rates for a second transplant due to sensitization. Although sensitization will affect subsequent transplant rates, the current Kidney Allocation System has demonstrated an ability to transplant in those who are sensitized (≤98%) at a rate that is not very different from those less sensitized.…”

“…6 , 7 , 8 , 9 Rates of preemptive transplant (another transplant before the transition to dialysis) after a failed first transplant were 20% for an LD and 15% for a DD transplant. 10 , 11 At baseline, we assumed 10% of LD kidneys would not be available in the DD-LD sequence. We assumed the third transplant would not be preemptive.…”

Outcomes of small pediatric donor kidney transplants according to donor weight

“…Higher sensitization after brief exposure to a thrombosed living donor kidney was associated with a 37% reduction in the chance of a second transplant [19]. In young adults, the recipient's sensitization was higher after a failed first deceased donor when compared with a living donor, with consequent delay to a second transplant [20]. Early graft loss in adult kidney recipients was associated with high mortality rates in the first few months after transplantation, low re-listing rates, and increased risk of a subsequent early graft loss [21,22].…”

“…Recipient characteristics associated with increased risk of graft failure in 10-15 kg pediatric kidneys donor transplants were a recipient time in dialysis, morbid obesity (BMI >40), diabetes mellitus, and age over 60 years. 13 (12)(13)(14) 14 (12)(13)(14)(15) 17 (16)(17) 17 (16)(17)(18) 19 (19)(20) 20 (19)(20) 62 (45-74) DCD (%) In a sub-analysis, single kidney donors were stratified in 10, 11, 12, 13, and 14 kg weight to compare graft survival with the >20 kg single group. The Kaplan-Meier curve demonstrated that donors with weight <12 kg had an inferior survival.…”