Challenges and Advances in Kidney Paired Donation: National and Global Perspectives

Abstract

The concept of Kidney Paired Donation (KPD) was first described by Rapaport in 1986, enabling two ABO- or HLA- incompatible donor-recipient pairs to exchange donors and form compatible pairs (CPs). The first transplant using this concept occurred in South Korea in 1991, followed by Europe in 1999, the USA in 2000, and Portugal in 2013. Kidney exchange programs can range from simple two-pair exchanges to more complex arrangements involving three or more pairs and can include DD (deceased donor). International initiatives, such as the South Alliance for Transplant and Scandiatransplant, have successfully increased transplant numbers. Including CPs seeking higher immunological compatibility, or incorporating DD into transplant chains, further increases the number of transplants. More recently, the concept of Global Kidney Exchange has emerged, enabling exchanges between high- and low- income countries while ensuring medical care for pairs from low- income regions. This approach may enhance genetic diversity but raises important ethical and legal considerations. Participation in KPD programs increases the number of patients transplanted and reduces waiting times. Its success depends on the number of registered pairs, making access to information for nephrology consultants and its dissemination to the whole medical and non- medical community a priority.

This narrative review explores the evolution of KPD, the challenges of different kidney exchange types, and their implementation in Portugal. It also presents future perspectives, emphasizes public education and awareness, and provides a practical, accessible information source for the Portuguese population.

This narrative review was based on a targeted literature search conducted in PubMed and ScienceDirect up to May 2025, complemented by institutional documents and official data from the Portuguese Institute of Blood and Transplantation and the Global Observatory on Donation and Transplantation. Peer-reviewed articles, guidelines, registry- based studies, and institutional reports were selected when they addressed the clinical, immunological, organizational, logistical, ethical, or legal aspects of KPD. A total of 47 scientific publications and institutional documents were included in a qualitative narrative synthesis, with particular emphasis on the Portuguese experience.