A decade of ABO-incompatible kidney transplantation in the Netherlands

A.E. de Weerd, J.A.J.G. van den Brand, H. Bouwsma, A.P.J. de Vries, P.M.M. Dooper, J.S.F. Sanders, M. van Dijk, M.H.L. Christiaans, F.E. van Reekum, A.D. van Zuilen, F.J. Bemelman, M.S. van Sandwijk, A. Nurmohamed, M. van Agteren, M.G.H. Betjes, M.F.C. de Jong, M.C. Baas

Wednesday 13 march 2019

16:00 - 16:10h at Tropentheater

Categories: Best abstracts, Parallelsessie

Parallel session: Parallelsessie VIII – Best abstracts II

Background: In 2006, ABO-incompatible (ABOi) kidney transplantation was introduced in the Netherlands. It has become a standard procedure in many centers. We compared graft and patient survival between ABOi and ABO-compatible (ABOc) transplant recipients.

Methods: Data on all kidney transplantations performed since the first ABOi transplantation were obtained from the Dutch Organ Transplant Registry. Outcomes for ABOi, ABOc living and ABOc deceased donor transplantations were recorded. Using propensity scores, ABOi recipients were matched to deceased donor recipients in a 1:4 ratio. Likewise the ABOi recipients were matched to ABOc living donor recipients. The propensity score model included transplant center, recipient age, number of transplantations, peak panel-reactive antibodies (PRA) and dialysis duration.

Results: 10.689 Kidney transplantations were performed between March 2006 and January 2018, of which 277 ABOi procedures. If patients received a second ABOc kidney allograft in this period, only the first ABOc transplantation was included. 9.718 individual ABOc recipients were identified. After matching, baseline characteristics for the ABOi compared to the ABOc-living donor group were: recipient mean age 54 vs 53 years, donor mean age 55 vs 54 years, mean total HLA mismatches 3.2 vs 3.5, PRA 4% in both groups, retransplant 16% vs 8% and median dialysis duration 244 vs 195 days. 66% of ABOi recipients were blood group O. Induction therapies in ABOi recipients consisted of rituximab alone (57%), rituximab with basiliximab (13%) or alemtuzumab (30%). ABOi recipients had a higher risk of death-censored graft failure compared to ABOc living donor recipients (HR=2.22, 95%CI 1.36-3.64) and higher risk of death (HR=1.17, 95%CI 0.73-1.89), mostly in the first year of follow-up. Conversely, outcome risks were lower in the ABOi group compared to the deceased donor cohort (death-censored graft survival HR=0.66, 95%CI 0.43-1.01; and patient death HR=0.58, 95%CI 0.36-0.92).

Conclusions: ABO-incompatible kidney transplantation is favorable compared to deceased donor transplantation, but outcomes are inferior to matched ABOc living donor recipients. We are currently analyzing modifiable risk factors in order to improve outcomes after ABOi kidney transplantation.