KARMA study

KARMA : Kidney retransplantation : impact of Avoidance of Repeat Mismatched HLA Antigens on waiting time


In candidates for re-transplantation, repeat HLA-antigen mismatches with the previous donor have traditionally been avoided by transplant physicians and HLA laboratories. Whether this precaution remains beneficial in an era with widely available sensitive histocompatibility assays is not known. Even if a strategy based on systematic avoidance of repeat mismatches has the potential to improve donor and recipient compatibility, this advantage should be balanced against the consequences in terms of waiting time. The KARMA study is designed to investigate whether allowing transplantation with selected repeat HLA antigen mismatches would improve vPRA and estimated waiting time in patients listed for a second kidney transplantation in Belgium between 2010 and 2022. In addition, the study will investigate whether repeat HLA antigen mismatches have an impact on graft outcomes after second kidney transplantation in this contemporary Belgian cohort.

Study design

Retrospective registry analysis and retrospective national multi-center cohort

Coordinating investigators

L Pipeleers, KM Wissing, MP Emonds