Pediatric deceased donor kidney transplant outcomes under the Kidney Allocation System.

The Kidney Allocation System (KAS) has resulted in fewer pediatric kidneys being allocated to pediatric deceased donor kidney transplant (pDDKT) recipients. This had prompted concerns that post-pDDKT outcomes may worsen. To study this, we used SRTR data to compare the outcomes of 953 pre-KAS pDDKT (age <18 years) recipients (December 4, 2012-December 3, 2014) with the outcomes of 934 post-KAS pDDKT recipients (December 4, 2014-December 3, 2016). We analyzed mortality and graft loss by using Cox regression, delayed graft function (DGF) by using logistic regression, and length of stay (LOS) by using negative binomial regression. Post-KAS recipients had longer pretransplant dialysis times (median 1.26 vs 1.07 years, P = .02) and were more often cPRA 100% (2.0% vs 0.1%, P = .001). Post-KAS recipients had less graft loss than pre-KAS recipients (hazard ratio [HR]: 0.35 0.540.83 , P = .005) but no statistically significant differences in mortality (HR: 0.29 0.721.83 , P = .5), DGF (odds ratio: 0.93 1.321.93 , P = .2), and LOS (LOS ratio: 0.96 1.061.19 , P = .4). After adjusting for donor-recipient characteristics, there were no statistically significant post-KAS differences in mortality (adjusted HR: 0.37 1.042.92 , P = .9), DGF (adjusted odds ratio: 0.94 1.412.13 , P = .1), or LOS (adjusted LOS ratio: 0.93 1.041.16 , P = .5). However, post-KAS pDDKT recipients still had less graft loss (adjusted HR: 0.38 0.590.91 , P = .02). KAS has had a mixed effect on short-term posttransplant outcomes for pDDKT recipients, although our results are limited by only 2 years of posttransplant follow-up.