THE SEARCH FOR AN HL‐A‐ AND ABO‐COMPATIBLE CADAVER ORGAN FOR TRANSPLANTATION: Probabilistic Asssessment of the Outlook

The degree to which discriminating criteria are asserted in the selection of cadaveric donor organs for transplantation depends on the probabilities of finding, within a tolerable waiting period, donors of different degrees of histocompatibility with the recipient. A means of assessing these probabilities is described, considering the HL-A and ABO factors. The theoretical development, together with available data on the frequencies of the various alleles, permits the construction of a simple table and nomogram for practical assessment of the probabilities. The necessary input information includes the estimate of the total number of potential donors that will become available within, the projected waiting period, together with the HL-A and ABO types of the recipient.