Innovative strategies in kidney paired donation: single-center experience achieving the highest annual transplant volume globally

BackgroundKidney Paired Donation (KPD) programs expand transplant opportunities for immunologically incompatible donor-recipient pairs. This study describes the operational framework and clinical outcomes of a high-volume, single-center KPD program, which became the highest-volume center globally in 2024.MethodsWe analyzed all kidney transplants performed through our KPD program between January and December 2024. The program aimed to achieve full HLA and ABO compatibility for incompatible pairs, while also incorporating additional strategies: inclusion of compatible pairs to improve HLA matching, acceptance of ABO quasi-compatible matches (e.g., A2 donors to O or B recipients), low-risk HLA-incompatible matching for HLA-incompatible candidates with cPRA >80%, and ABO-incompatible matching for those with cPRA >95%.ResultsA total of 135 patients (121 adults, 14 pediatrics) underwent KPD-facilitated transplantation, including 69 HLA-incompatible (51.1%), 37 ABO-incompatible (27.4%), and 29 compatible (21.5%) pairs. Females comprised 60.7% of the cohort, with a significantly higher proportion in the HLA-incompatible group (p < 0.001). HLA-incompatible recipients were older than others (mean age 42.5 years, p < 0.001). Most transplants (93.3%) occurred through 2- to 5-way closed chains, with the remainder via domino chains (6.7%). At baseline, 25% of patients were very highly sensitized (cPRA ≥95%) HLA- incompatible recipients, and ABO-incompatible recipients were blood group O individuals whose intended donors had A1 or B blood groups (high risk combinations). Following matching, 70% of patients achieved full HLA and ABO compatibility, while 30% underwent transplantation with acceptable immunologic risk (i.e. low-risk HLA incompatibility and/or ABO incompatibility). Early post-transplant outcomes were favorable, with a mean serum creatinine of 87.2 µmol/L. Acute rejection occurred in 6.7% of patients, antibody-mediated rejection in 0.7%, and graft loss in 0.7%.ConclusionOur single-center experience demonstrates the feasibility and effectiveness of a high-volume KPD program in overcoming immunologic barriers to kidney transplantation. Strategic inclusion of compatible pairs, ABO quasi-compatible matching, low-risk HLA-incompatible, and ABO-incompatible matchings significantly increased access for difficult-to-match recipients. This model may serve as a replicable framework for other high-capacity transplant centers seeking to expand transplant access and improve outcomes for complex patient populations.