Significance of HLA Antibody Detected by PRA-Bead Method in Kidney Transplant Outcomes P. Wiwattanathum a , A. Ingsathit a , D. Thammanichanond b , T. Mongkolsuk b , and V. Sumethkul a, * a Division of Nephrology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand; and b Histocompatibility and Immunogenetics Laboratory, Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand ABSTRACT Background. The impact of specific HLA antibodies on the allograft function in the Luminex era is not clearly known. This study aimed to investigate kidney transplantation outcomes in patients with different anti-HLA antibody status as detected by Luminex PRA. Methods. This retrospective study included 106 deceased-donor kidney transplantation (DDKT) patients divided into 3 groups by PRA status as detected by PRA-bead: (1) PRA ¼ 0; (2) positive PRA but with negative antibody against donor’s HLA antigens; and (3) positive PRA with positive anti-HLA antibody specificity against donor’s HLA antigens. Results. There were 65, 23, and 18 patients in groups 1, 2, and 3, respectively. Early allograft rejections were highest in group 3 (22.2%) (P ¼ .02). In multivariate analysis, delayed graft function was the only factor that was associated with allograft rejection (hazard ratio, 8.9; 95% confidence interval, 1.9e39.8; P ¼ .004). Estimated glomerular filtration rates at 1 year of the 3 groups were 54.6, 55.8, and 60.0 mL/min (P ¼ .71). One-year allograft failure and death were not different among the 3 groups. Expanded-criteria deceased donors were associated with both allograft failure (P ¼ .003) and patient death (P ¼ .02). Conclusions. Anti-HLA antibody as detected by Luminex PRA was associated with early allograft rejection but not graft or patient survival. The effect of newer treatment modalities can improve the outcomes of PRA-positive patients to be similar to nonsensitized patients at 1 year. H IGH PANEL-REACTIVE ANTIBODY (PRA) level is associated with increased risk of allograft rejection, allograft loss, and patient death [1e3]. However, there is no information about outcome of positive PRA but with negative antibody against the donor’s HLA antigens compared with positive PRA with positive anti-HLA antibody specificity against the donor’s HLA antigens, as detected by means of Luminex PRA-bead. Factors other than PRA level can affect allograft outcomes. The present study aimed to compare kidney transplantation outcomes among recipients who had different degrees of sensitization detected by PRA-bead technique. METHODS Patients During a 1-year study period, we included patients who were: 1) deceased-donor kidney transplantation (DDKT) recipients; 2) 15 years of age; and 3) negative cross-match result at the time of transplantation. We excluded recipients who had combined solid organ transplantation. The impact of pre-transplantation donor- specific antibodies (DSA) was not examined in this study. The study population was stratified into 3 groups according to PRA status as detected with the use of PRA-bead, namely: group (G) 1: PRA ¼ 0 (no HLA antibody identified by PRA-bead); G2: positive PRA but negative antibody against donor’s HLA antigens and; G3: positive PRA with positive anti-HLA antibody specificity against donor’s HLA antigens. Types of DDKT were classified as standard-criteria donor (SCD), acute kidney injury (AKI) donor *Address correspondence to Vasant Sumethkul, Division of Nephrology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama VI Road, Ratchatewi, Bangkok 10400, Thailand. E-mail: vasant.sum@mahidol.ac.th ª 2016 Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010-1710 0041-1345/16 http://dx.doi.org/10.1016/j.transproceed.2016.02.029 Transplantation Proceedings, 48, 761e765 (2016) 761