[Correspondence] Directed organ donation and deceased donor-initiated kidney chains
In many instances, transplants cannot be performed because of incompatibility (such as incompatible blood type or crossmatch) among donors and recipients. A way to address this issue is by means of donor exchanges, in which incompatible pairs are enrolled in a registry. Registries can lead to paired exchanges or to donor chains. In chains, a non-directed (altruistic) donor initiates a sequence of transplants that culminates with a so-called bridge donor. Studies have estimated that a non-directed donor triggers on average 4·8–6 transplants (if donor is blood type O).