Kidney Transplantation Results in Very Highly Sensitized Patients Included in a Virtual Crossmatch Program: Analysis of Kidney Pairs

Background: Kidney transplantation in highly-sensitized (HS) patients can improve with organ-exchange strategies based on virtual crossmatch (V-XM). Experience in very-HS patients is limited.

Methods: In June 2012, Andalusia started a V-XM protocol for very-HS patients (calculated panel reactive antibodies ≥95%). After organ allocation a cytotoxic-XM performed immediately before transplantation had to be negative for surgery to proceed. We analyzed results up until December 2015. Whenever possible we also compared the course of the recipient (non-HS) of the other kidney from the same donor.

Results: Of the 57 grafts, 52 kidney transplantations were performed (the pretransplantation cytotoxic-XM was positive in 5; predictive value 91.3%). Five patients (9.6%) experienced acute rejection (4 antibody-mediated rejections [AMRs]; 7.6%). Donor-specific antibodies developed in 10 patients. No patient died. One-year graft survival was 98%. We compared the course of the non-HS recipient of the other kidney, excluding cases with no pair (n = 5), pairs who were children recipients (n = 3), pancreas-kidney recipients (n = 5), or pairs already included in the V-XM protocol (n = 4). Finally, 35 pairs were studied. More HS-patients developed donor-specific antibodies (P = .016). No significant differences were seen in acute rejection, but AMR was more common (P = .057). No deaths occurred in either group, and there were no differences in graft survival or renal function.

Conclusions: Although a few patients still developed AMR, our V-XM based protocol with a final pretransplantation cytotoxic-XM achieved very satisfactory results. Although the number of patients was limited, the initial survival of these high-risk recipients was comparable to the controls.