Article Donor-Specific Antibodies after Ceasing Immunosuppressive Therapy, with or without an

Background and objectives Within the last few years, anti–human leukocyte antigen detection assays have sig-nificantly improved. This study asked, using the Luminex single-antigen assay, whether an allograft nephrec-tomy allowed donor-specific alloantibodies to appear that were not previously detected in the serum when the failed kidney was still in place. Design, setting, participants, &measurementsAfter losing the kidney allograft and stopping immunosuppressive therapy, the proportions of donor-specific alloantibodies and nondonor-specific alloantibodies were compared in patients who had (n=48; group I) and had not (n=21; group II) undergone an allograft nephrectomy. Allograft nephrectomies were performed at 150 days after kidney allograft loss, and the time between allograft nephrec-tomy and last follow-up was 5386347 days. ResultsAt kidney allograft loss, donor-specific alloantibodieswere detected in three group II patients (14.2%) and six group I patients (12.5%). At last follow-up, donor-specific alloantibodies were detected in 11 patients (52.4%) without and 39 patients (81%) with an allograft nephrectomy (P=0.02). Anti–human leukocyte antigen class I donor-specific alloantibodies were positive in 23.8 % of group II and 77 % of group I patients (P,0.001); anti– human leukocyte antigen class II donor-specific alloantibodies were positive in 42.8 % of group II and 62.5 % of group I patients. Independent predictive factors for developing donor-specific alloantibodies after losing kidney allograft and stopping immunosuppressants were number of anti–human leukocyte antigen A/B mismatches at transplantation (zero versus one or more) and allograft nephrectomy. Conclusions The development of donor-specific alloantibodies was significantly greater in patients with a failed kidney who had undergone an allograft nephrectomy compared with those patients who had not undergone allograft nephrectomy