ABO-Incompatible Kidney Transplantation

Abstract

ABO-incompatible (ABOi) kidney transplantation has long been considered a contraindication to successful kidney transplantation. During the last 25 years, increasing organ shortage enforced the development of strategies to overcome the ABO antibody barrier. In the meantime, ABOi kidney transplantation has become a routine procedure with death-censored graft survival rates comparable to the rates in compatible transplantations. Desensitization is usually achieved by apheresis and B cell-depleting therapies that are accompanied by powerful immunosuppression. Anti-A/B antibodies are aimed to be below a certain threshold at the time of ABOi kidney transplantation and during the first 2 weeks after surgery. Thereafter, even a rebound of anti-A/B antibodies does not appear to harm the kidney transplant, a phenomenon that is called accommodation, but is poorly understood. There is still concern, however, that infectious complications such as viral disease, Pneumocystis jirovecii pneumonia, and severe urinary tract infections are increased after ABOi transplantations. Recent data from the Collaborative Transplant Study show that during the first year after kidney transplantation, one additional patient death from an infectious complication occurs in 100 ABOi kidney transplant recipients. Herein, we review the recent evidence on ABOi kidney transplantation with a focus on desensitization strategies and respective outcomes.

Keywords: ABO incompatible; antibodies; desensitization; kidney transplantation; survival.

Figure 1

Overview of desensitization protocols for ABO-incompatible (ABOi) living donor kidney transplantation. (A) Scheme for a standard desensitization protocol performed by the majority of centers with modifications in the utilization of desensitization devices, and (B) desensitization protocol for ABOi living donor kidney transplantation at the University of Heidelberg. Anti-CD20 therapy is usually performed with rituximab 375 mg/m², anti-IL-2R therapy is performed with basiliximab 20 mg [modified from Ref. (8)]. IA, immunoadsorption; IVIg, intravenous immunoglobulin; PP, plasmapheresis.

Figure 2

Cumulative incidence of (A) death-censored graft survival and (B) patient survival in recipients of an ABO-incompatible (ABOi) living donor graft and matched controls receiving an ABO-compatible (ABOc) living donor graft [updated Figure 1 of Ref. (15)]. (C) Cumulative incidence of death-censored graft survival in recipients of an ABOi living donor graft with and without anti-CD20 antibody treatment [updated Figure 4 of Ref. (15)]. (D) Cumulative incidence of death due to infection in recipients of an ABOi living donor graft and matched controls receiving an ABOc living donor graft [updated Figure 3 of Ref. (15)].