Implementation of a National Priority Allocation System for Hypersensitized Patients in Spain, Based on Virtual Crossmatch: Initial Results

Abstract

Access to kidney transplantation for patients with high levels of antibodies against HLA is a major challenge. This issue makes it difficult to detect compatible donors for those patients in a certain geographical area. Consequently, hypersensitized patients remain on the waiting list for long periods and their quality of life deteriorates. Our purpose was to increase access to transplantation for highly sensitized patients by developing a national priority allocation system based on virtual crossmatch. Between June 15, 2015, and May 15, 2016, 675 patients on the kidney transplant waiting list with calculated panel-reactive antibodies ≥98% and undergoing dialysis for at least 12 months were included in the study; 86.1% of the patients had previously received at least one transplant. Solid-phase immunoassays were used to identify class I and II HLA antibodies in all patients. Participating hospitals assigned to the program one of the kidneys of every identified brain-dead real donor between 18 and 70 years old. Survival data were collected for the recipients transplanted between June 15, 2015, and December 31, 2015. In all, 475 (290 male and 185 female) brain-dead donors were assigned to the program. Virtual crossmatch was negative for 191 (41%) donors, 149 offers were accepted, and 102 (21.8%) kidneys were transplanted. At the end of the study, patient and graft survival were both 93.4%. The implementation of a national prioritization system based on virtual crossmatch increased access to transplantation for highly sensitized patients, with excellent results in terms of patient and graft survival.