Combined liver-kidney transplantation with positive crossmatch: Role of delayed kidney transplantation

Background: Positive crossmatch (XM+) combined liver-kidney transplantation due to preformed donor-specific human leukocyte antigen antibodies has produced mixed results. We sought to understand the role of delayed kidney transplant approach in XM+ combined liver-kidney transplantations. Methods: XM+ combined liver-kidney transplantations were retrospectively reviewed. T-and B-cell XM, complement-dependent cytotoxic crossmatch, and flow cytometric crossmatch were performed prospectively. Results: Of 183 combined liver-kidney transplantations performed (2002-2019), 114 (62%) were with delayed kidney transplant approach and 19 (19 of 183, 10%) were XM+. Of 19 XM+ combined liver-kidney transplantations, kidney transplant was delayed in 14 by an average of 47 hours (range 24-64 hours) from liver transplant. There was a significant reduction in both class I (mean pre-liver transplant mean fluorescence intensity (MFI) 26,230 versus mean post-liver transplant and pre-delayed kidney transplant MFI 3,272, P = .01) and total MFI (mean pre-liver transplant MFI 27,233 vs mean post liver transplant and predelayed kidney transplant MFI 11,469, P = .01). However, there was no significant change in the MFI of class II donor-specific antibodies (mean pre-liver transplant MFI 17,899 versus post-liver transplant and pre-delayed kidney transplant MFI 14,341, P = .19). None of XM+ delayed kidney transplants had delayed graft function, and there was no antibody-mediated rejection. One-year patient survival for the XM+ combined liver-kidney transplantation with delayed kidney transplant approach was 92.9%, which is comparable to patient survival of XMcombined liver-kidney transplantation. Whereas patient survival in recipients before delayed approach (simultaneous; n = 5) was 40% when liver-kidney transplants were performed simultaneously (P = .06). Conclusion: In sensitized combined liver-kidney transplantation recipients, the delayed kidney transplant approach is associated with a significant reduction in total and class I donor-specific antibodies after liver transplant before kidney transplant, enabling therapeutic interventions such as plasmapheresis, if needed, providing optimal outcomes similar to crossmatch recipients. (c) 2021 Elsevier Inc. All rights reserved.

Automated summary

The study indicates that the delayed kidney transplant approach in XM+ combined liver-kidney transplantations leads to a significant reduction in total and class I donor-specific antibodies, without delayed graft function or antibody-mediated rejection. One-year patient survival with this approach is comparable to that of crossmatch recipients.