An Interesting Case of Renal Transplantation: Resolving Discrepancies in Histocompatibility Testing

Histocompatibility testing plays an important role in the success of renal transplantation outcome by ensuring optimal donor recipient compatibility. Developments in testing methods have increased transplant success, but discrepancies between different tests can sometimes make it harder to make the best clinical decisions. We report a case of a renal transplant patient whose single antigen bead test showed donor-specific antibody against HLA-DRB1*11:04 and HLA-DRB1*14:04, but the CDCXM and FCXM tests were negative. A review of the literature showed that the patient’s homozygosity for HLA-DRB1*07 could explain the negative crossmatch due to epitope-specific (25R) antibody reactivity. This case highlights the need for using multiple tests and considering epitope-level assessment in improving transplant decision-making.