Outcomes of Pediatric Kidney Transplantation in Recipients of a Previous Non-Renal Solid Organ Transplant.

Children who receive a non-renal solid organ transplant may develop secondary renal failure requiring kidney transplantation. We investigated outcomes of 165 pediatric kidney transplant recipients who previously received a heart, lung, or liver transplant using data from 1988 to 2012 reported to the United Network for Organ Sharing. Patient and allograft survival were compared with 330 matched primary kidney transplant (PKT) recipients. Kidney transplantation after solid organ transplant (KASOT) recipients experienced similar allograft survival: 5- and 10-year graft survival was 78% and 60% in KASOT recipients, compared to 80% and 61% in PKT recipients (p = 0.69). However, KASOT recipients demonstrated worse 10-year patient survival (75% KASOT vs. 97% PKT, p < 0.001). Competing risks analysis indicated that KASOT recipients more often experienced graft loss due to patient death (p < 0.001), whereas allograft failure per se was more common in PKT recipients (p = 0.01). To study more recent outcomes, kidney transplants performed from 2006 to 2012 were separately investigated. Since 2006, KASOT and PKT recipients had similar 5-year graft survival (82% KASOT vs. 83% PKT, p = 0.48), although 5-year patient survival of KASOT recipients remained inferior (90% KASOT vs. 98% PKT, p < 0.001). We conclude that despite decreased patient survival, kidney allograft outcomes in pediatric KASOT recipients are comparable to those of PKT recipients.

Clinical Practice of Steroid Avoidance in Pediatric Kidney Transplantation.

Steroid-avoidance protocols have recently gained popularity in pediatric kidney transplantation. We investigated the clinical practice of steroid avoidance among 9494 kidney transplant recipients at 124 transplant centers between 2000 and 2012 in the Organ Procurement and Transplantation Network database. The practice of steroid avoidance increased during the study period and demonstrated significant variability among transplant centers. From 2008 to 2012, 39% of transplant centers used steroid avoidance in <10% of all discharged transplant recipients. Twenty-one percent of transplant centers practiced steroid avoidance in 10-40% of transplant recipients, and 40% of transplant centers used steroid avoidance in >40% of discharged patients. Children receiving steroid avoidance more frequently received induction with lymphocyte-depleting agents. Repeat kidney transplants were the least likely to receive steroid avoidance. Children who received a deceased donor kidney, underwent pretransplant dialysis, were highly sensitized, or had glomerular kidney disease or delayed graft function were also less likely to receive steroid avoidance. The variation in practice between centers remained highly significant (p < 0.0001) after adjustment for all patient- and center-level factors in multivariate analysis. We conclude that significant differences in the practice of steroid avoidance among transplant centers remain unexplained and may reflect uncertainty about the safety and efficacy of steroid-avoidance protocols.

Outcomes of steroid-avoidance protocols in pediatric kidney transplant recipients.

Advances in immunosuppression have facilitated increased use of steroid-avoidance protocols in pediatric kidney transplantation. To evaluate such steroid avoidance, a retrospective cohort analysis of pediatric kidney transplant recipients between 2002 and 2009 in the United Network for Organ Sharing database was performed. Outcomes (acute rejection and graft loss) in steroid-based and steroid-avoidance protocols were assessed in 4627 children who received tacrolimus and mycophenolate immunosuppression and did not have multiorgan transplants. Compared to steroid-based protocols, steroid avoidance was associated with decreased risk of acute rejection at 6 months posttransplant (8.3% vs. 10.9%, p = 0.02) and improved 5-year graft survival (84% vs. 78%, p < 0.001). However, patients not receiving steroids experienced less delayed graft function (p = 0.01) and pretransplant dialysis, were less likely to be African-American and more frequently received a first transplant from a living donor (all p < 0.001). In multivariate analysis, steroid avoidance trended toward decreased acute rejection at 6 months, but this no longer reached statistical significance, and there was no association of steroid avoidance with graft loss. We conclude that, in clinical practice, steroid avoidance appears safe with regard to graft rejection and loss in pediatric kidney transplant recipients at lower immunologic risk.