Donor-specific HLA antibodies and graft function in children after renal transplantation

The presence of circulating donor-specific human leukocyte antigen antibodies (HLA-DSA) has been associated with chronic antibody-mediated rejection, leading to progressive graft dysfunction and poor graft survival. The aim of this study was to investigate the incidence and significance of HLA-DSA in paediatric renal transplantation (RTx) patients. A total of 294 post-transplant serum samples from 123 RTx patients were retrospectively analysed for HLA antibodies. Positive samples were further tested for HLA-DSA by a Luminex Single Antigen bead assay. The antibody findings were correlated to measured glomerular filtration rate (GFR) and clinical outcome. HLA antibodies were detected in half of the routine samples (140/294) taken 1 month to 10 years after RTx, and 40% (62/140) of these were HLA-DSA. Overall, one-third (42/123) of the patients had HLA-DSA, which mostly (65%) reacted against class II antigens. Detection of HLA-DSA was not associated with poor GFR at the time of sampling, and no exceptional deterioration of GFR after the HLA-DSA detection was noted in individual patients regardless of the antibody level. The presence of HLA-DSA in the first 2 years posttransplantation was not associated with poorer graft function later on. Detection of HLA antibodies is common in children after RTx, and this finding, as such, does not predict any deterioration of graft function.