OBJECTIVE: To evaluate the influence of pre-transplant recipient sensitization on the outcome of 1-haploidentical live related donor (LRD) kidney transplants. METHOD: We reviewed 141 consecutive cyclosporine-treated adult haploidentical first transplants for which panel reactive antibody (PRA) levels were available. Patients were divided into three groups according to their peak PRA levels: group I, PRA = 0 (n = 97); group II, PRA = 1-50% (n = 24); and group III, PRA = 51-100% (n = 20). RESULTS: Differences in PRA were associated with significant differences in short- and longer-term graft survival, unrelated to patient survival. Graft survival at 1, 3, and 5 yr was only 74, 40, and 27% in group III, compared to 92, 87, and 52% in group II, and 96, 91, and 85% in group I (p