Anti-HLA Antibodies Posttransplantation in Children: Do We Know What It Means?

Abstract Objective Anti-HLA antibodies posttransplantation are associated with the appearance of acute and chronic rejection. The goal of this study was to determine the association between the presence of anti-HLA antibodies posttransplantation in children and the clinical outcome. Patients and Methods We studied the presence and the level of class I and II anti-HLA antibodies by microbead technology (Luminex) in 32 children after kidney transplantation; 87% underwent a first transplantation. Their mean age was 13.9 ± 2.52 years. When anti-HLA was positive, 60% of children showed an increase in creatinine within the previous 3 months. The statistical analysis was performed with the SPSS 9.0 program. Results Only 4/32 children displayed class I anti-HLA antibodies at low levels (5–7.2) and 43% class II anti-HLA antibodies (level: 5–308). We did not observe an association between the presence of antibodies and age, sex, type of donor, immunosuppression, hypertension, proteinuria, time from transplantation, or reason to evaluate antibodies; 37.5% showed good graft function. The presence of anti-HLA antibodies posttransplantation was associated with retransplantations and with the percentage of antibodies by panel-reactive antibodies. There was trend towards an association with a previous acute rejection episode ( P = .072); 62.5% of children with C4d-positive biopsies displayed anti-HLA antibodies vs 20% of those who were C4d-negative ( P = .088). Graft survival was 100%. Conclusions The presence of anti-HLA antibodies posttransplantation was influenced by pretransplantation factors—previous level of anti-HLA antibodies, retransplantation, DR matching— and also by posttransplantation factors, such as the occurrence of an acute rejection episode.