Eplet-Based Matching and Disparities in Kidney Transplant Access

Prevention of eplet mismatches (EpMM) is associated with better long-term kidney transplant outcomes. Researchers led by Ross Doyle, MB BCh, BAO, PhD, investigated whether eplet-based matching could lead to disparities in deceased donor (DD) kidney transplantation access. Their results were presented at the American Transplant Congress 2024.

The researchers conducted a retrospective analysis of consecutive DD allocation sequence runs over 3 months. The patients studied were waitlisted transplant candidates from different ethnic groups in British Columbia. Only those who were blood-group-compatible and had a negative virtual crossmatch could appear on the allocation sequence and be considered for a kidney offer.

The team used high-resolution human leukocyte antigen (HLA) genotypes of donors and recipients to perform eplet mismatch analysis. EpMM was calculated based on the single molecule eplet mismatch load at HLA-DR (DR) and HLA-DQ (DQ), with DR <7 and DQ <9 being low risk. The researchers calculated the proportion of organ offers with low EpMM among ABO- and HLA-compatible active waitlisted candidates.

There were 51 DD and 260 active waitlisted candidates during the study period. A low EpMM donor offer for both donor kidneys could be accomplished for 57% of DDs. Within each allocation run, a median of 14% (interquartile range, 8%-21%) of candidates had a low EpMM kidney offer, while 56% of waitlisted candidates never matched with a low EpMM kidney after 51 allocation runs over the study period. Among White candidates, 52% had no low EpMM offers, 27% had one low EpMM offer, and 21% had several low EpMM kidney offers. These percentages were similar among other ethnic groups (X 2=6.5; P=.77).

“Analysis of actual allocation sequence runs in a single multiethnic transplant center showed that kidney allocation based on eplet matching appeared to be possible for the majority of deceased donors without exacerbating disparities in access to transplantation,” the authors concluded.

Source: Doyle R, Tran J, Hendren E, et al. The impact of eplet based kidney allocation on access to transplant among candidates of different ethnicity: a real world assessment. Abstract #346. Presented at the American Transplant Congress 2024; June 1-5, 2024; Philadelphia, Pennsylvania.