The paradigm shift of virtual crossmatch for deceased donor kidney allocation in the United States, 2015 - 2024

Virtual Crossmatch (VXM) analysis, a specialized evaluation of immunologic compatibility based on patient anti-HLA antibody testing and donor HLA genotyping, is an invaluable tool in organ transplantation. While the utility of VXM has been clearly established, uncertainty persists regarding transitioning from traditional Cellular Crossmatch (CXM) testing to VXM as an independent pre-transplant assessment of immunologic compatibility. Here we examine allocation and transplant outcome data to identify changing patterns in use of VXM for deceased donor kidney transplantation in the United States (U.S.).

Organ Procurement and Transplantation Network data for 139,288 deceased donor kidney transplants performed in the U.S. between 2015 and 2024 was examined. Data analyzed included performance of prospective CXM, recipient sensitization, and 90-day outcomes.

Transplantation of deceased donor kidneys without prospective CXM increased from 7.47% in 2015 to 47.16% of all kidneys in 2024, including 23.96% of the most highly sensitized patients (cPRA > 99.9%). Kidneys transplanted without prospective CXM had 90-day graft survival, outcomes comparable to transplants relying on CXM testing.

This data demonstrates that despite the variability in how VXM is performed, VXM in the absence of traditional CXM is an increasingly utilized approach in kidney transplantation with safety comparable to traditional CXM testing.