The Impact of Virtual Crossmatch on Cold Ischemic Times and Outcomes Following Kidney Transplantation

Abstract

Background Prolonged cold ischemic time (CIT) in deceased donor kidney transplantation (DDKT) has been associated with adverse graft outcomes. Virtual crossmatch (VXM) facilitates reliable prediction of crossmatch results based on the profile of human leukocyte antigen antibodies of the recipient and the donor in reduced time compared with a physical crossmatch (PXM). We hypothesized a shorter CIT since the implementation of the VXM in recipients of DDKT. Methods We conducted a retrospective cohort study of consecutive adult recipients of DDKT. The data were analyzed for differences in CIT before and after the implementation of VXM. Results After the exclusion of 59 recipients (age less than 18 years and/or CIT ≥ 20 hours), our study compared outcomes of 81 PXMs from February to June 2018 against 68 VXMs from February to June 2019. There were no statistical differences between groups based on donor age ( P = .09), donor type ( P = .38), kidney donor profile index ( P = .43), or delayed graft function ( P = .20). Recipients with VXM were older (58 vs 51 years , P = .002) and had a higher estimated post-transplant survival score (59% vs 46% , P = .01). The CIT was significantly lower for the VXM group ( P = .04). Conclusion Our study demonstrated a significantly shorter CIT with VXM in DDKT recipients. Our study was limited with small sample size, but the trend of increased graft survival with higher estimated post-transplant scores and older recipients is encouraging as the donor pool expands with marginal kidneys and national sharing.

Early Effect of the Circular Model of Kidney Allocation in the United States

“…This will identify unintended consequences and measure changes in allocation-related processes such as use of donor kidney biopsy, machine perfusion, and virtual cross-match (VXM), which have an effect on CIT and delayed graft function (DGF). 6 –12…”

“…This will identify unintended consequences and measure changes in allocation-related processes such as use of donor kidney biopsy, machine perfusion, and virtual cross-match (VXM), which have an effect on CIT and delayed graft function (DGF). [6][7][8][9][10][11][12] Using data from the Scientific Registry of Transplant Recipients (SRTR), we evaluated the early effect of the new KAS250 allocation policy on kidney utilization, CIT, DGF, and changes in allocation-related practices (biopsy, machine perfusion, and VXM use). Because the new allocation policy moves away from DSA-based allocation, we evaluated these changes for kidneys transplanted within and outside of the "traditional" donor organ procurement organization (OPO) boundaries.…”

Principles of Virtual Crossmatch Testing for Kidney Transplantation

“…After allocation, at the transplant center level, VXM may be applied both for non-sensitized patients and sensitized patients (Figure 1). Several transplant centers have reported their success with proceeding to transplant based on VXM results and eliminating pretransplant PXM [35][36][37][38][39][40][41][42] . The need for pretransplant PXM increases cold ischemia time-the time from clamping of the donor renal artery to restoration of blood flow after transplantation.…”

“…Several transplant centers have reported their success with proceeding to transplant based on VXM results and eliminating pretransplant PXM. 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 The need for pretransplant PXM increases cold ischemia time—the time from clamping of the donor renal artery to restoration of blood flow after transplantation. Cold ischemia is associated with increased risk for delayed graft function, organ discards, and graft failure.…”

Differences in Responses of Immunosuppressed Kidney Transplant Patients to Moderna mRNA-1273 versus Pfizer-BioNTech

“…However, even three mRNA doses did not achieve adequate levels of antibodies, thus requiring even more doses [ 17 ]. Since an effective vaccination is needed for these vulnerable patients [ 18 , 19 ], a much better understanding of the immune mechanism with a possible involvement of regulatory cells is needed. Current recommendations advise vaccination prior to transplantation whenever possible [ 20 ] and a repeated booster vaccination [ 21 ].…”