Pretransplant Donor-Specific HLA Antibodies Detected by Single Antigen Bead Flow Cytometry: Risk Factors and Outcomes After Kidney Transplantation

• Published in: Transplantation proceedings 2012-11, Vol.44 (9), p.2529-2531
• Main Authors: Kanter Berga, J, Sancho Calabuig, A, Gavela Martinez, E, Puig Alcaraz, N, Beltran Catalan, S, Avila Bernabeu, A, Crespo Albiach, J, Montoro, J.A, Pallardo Mateu, L.M
• Format: Article
• Language: English
• Subjects: Acute Disease; Adult; Aged; Biological and medical sciences; Biomarkers - blood; Chronic Disease; Cytotoxicity Tests, Immunologic; Epidemiology; Female; Flow Cytometry; Fundamental and applied biological sciences. Psychology; Fundamental immunology; General aspects; Graft Rejection - immunology; Graft Survival; Histocompatibility; Histocompatibility Testing - methods; HLA Antigens - blood; Humans; Isoantibodies - blood; Kaplan-Meier Estimate; Kidney Transplantation - adverse effects; Kidney Transplantation - immunology; Kidney Transplantation - mortality; Logistic Models; Male; Medical sciences; Middle Aged; Multivariate Analysis; Predictive Value of Tests; Proportional Hazards Models; Public health. Hygiene; Public health. Hygiene-occupational medicine; Retrospective Studies; Risk Assessment; Risk Factors; Sex Factors; Spain; Surgery; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the urinary system; Time Factors; Tissue, organ and graft immunology; Treatment Outcome
• ISSN: 0041-1345; 1873-2623
• DOI: 10.1016/j.transproceed.2012.09.102

Abstract Background The clinical significance of pretransplant donor-specific antibodies (pre-Tx DSAs) detected by single antigen bead flow cytometry (SAB-FC) remains unclear. Our aim was to investigate the impact that pre-Tx DSAs detected by SAB-FC have on the early and late clinical outcomes. Patients and methods We retrospectively tested stored frozen pre-Tx sera from 222 deceased-donor kidney transplants performed between November 1997 and November 2006. All patients had a negative complement-dependent cytotoxicity (CDC) cross-match with the donor. Median follow up was 5.1 years. Results Twenty-two (10%) patients had pre-Tx HLA antibodies detected by CDC. Pre-Tx HLA antibodies were detected using SAB-FC in the sera of 46 (20.7%) patients; 36 (16.2%) of them presented pre-Tx DSAs, 18 had class I antibodies, 9 class II, and 9 patients presented both classes. Mean pre-Tx DSA class I/II was 2360/1972 (MFI) mean fluorescence index in non CDC-sensitized patients. Pre-Tx DSAs were associated with female sex, retransplants, and pretransplant transfusions. Patients with Pre-Tx DSAs more than 1000 MFI and negative CDC screening presented a higher percentage of delayed graft function (61.1% versus 38.9%), more episodes of acute vascular rejection (33.3% versus 13.7%), and chronic rejection as the cause of allograft failure (22.2% versus 9.7%) compared with non-pre-Tx DSAs patients. Five-year allograft survival was significantly worse in patients with pre-Tx DSA (68.5% versus 82%, P = .006) and in patients with pre-Tx DSA class II more than 1000 MFI (43% versus 82%, P = .009). We didn't find differences in patient survival. Discussion Pre-Tx DSAs detected by SAB-FC were more frequent in female recipients, and they were associated with acute vascular and chronic rejection and a poorer graft outcome.