Association of post‐transplant donor‐specific HLA antibody with liver graft fibrosis during long‐term follow‐up after pediatric liver transplantation

The aim of this study was to evaluate the significance of post‐transplant DSA as a predictor of liver fibrosis during long‐term follow‐up after pediatric LT. We evaluated the histological findings in 18 LT recipients who underwent liver biopsy after DSA screening. Liver fibrosis was scored based on the METAVIR fibrosis staging. Patients were divided into 2 groups based on histological findings, and clinical characteristics among patients with liver fibrosis were assessed. Of 18 patients, 7 were included in the fibrosis group. No significant between‐group differences were found regarding peritransplant characteristics, including age, sex, primary disease, ABO incompatibility, and immunosuppressive regimen. Episodes of acute rejection and non‐adherence to immunosuppressive drugs were comparable between both groups. The MFI for anti‐DR DSA and positive rate were significantly higher in the fibrosis group (1655 vs 216; P = .019, 86% vs 27%; P = .012, respectively). MFI for anti‐DQ DSA was higher in the fibrosis group, but non‐significantly (2052 vs 384; P = .46). Post‐transplant anti‐DR DSA is associated with graft fibrosis during long‐term follow‐up. This finding seems useful for the implementation of valid histological examinations of liver grafts for patients with higher MFI, especially for anti‐DR DSA, after pediatric LT.