Long term graft survival and rejection rate of zero-human leukocyte-antigen-mismatched deceased donor kidney transplant recipients: a retrospective multicentric cohort study.

BACKGROUND

Historically, human leukocyte antigen (HLA) matching has been a cornerstone of kidney transplantation (KT), with favorable outcomes. However, the survival benefit of KT with zero HLA mismatches appears to have decreased with the accumulation of transplantation experience and advancements in immunosuppressive therapies.

METHODS

This was a prospective observational cohort study based on data from the Korean Organ Transplantation Registry, including patients who underwent deceased donor KT from May 2014 to December 2022. A total of 3,350 KT patients were propensity score-matched at a 1:1 ratio and compared according to zero HLA mismatching (zero group) vs. non-zero HLA mismatching (non-zero group).

RESULTS

After matching, 276 patients in the zero group were compared to 276 patients in the non-zero group. Over a follow-up period of 38.4 ± 28.8 months, the use of immunosuppressants was similar between the two groups. Multivariable-adjusted hazard ratios of non-zero group vs. zero group were 1.63 (95% confidence interval [CI], 0.72-3.69; p = 0.24) for death censored graft failure, 1.62 (95% CI, 0.96-2.76; p = 0.07) for biopsy-proven rejection, 2.09 (95% CI, 0.87-5.00; p = 0.10) for death, 1.38 (95% CI, 1.02-1.86; p = 0.03) for posttransplant infection and 4.48 (95% CI, 1.52-13.25; p = 0.001) for antibody mediated rejection.

CONCLUSION

This study suggests that rigid adherence to HLA matching may be less critical than previously thought, particularly due to advancements in immunosuppressive therapies.