Autologous hematopoietic stem cell transplantation in a patient with relapsed diffuse large B-cell lymphoma and type 3 von Willebrand disease: a case report.

Autologous hematopoietic stem cell transplantation (auto-HSCT) is standard therapy for eligible patients with relapsed diffuse large B-cell lymphoma (DLBCL). Type 3 von Willebrand disease (VWD) poses additional haemostatic challenges during postconditioning aplasia. We report a 65-year-old man with DLBCL in second complete remission and type 3 VWD who underwent auto-HSCT. During bone marrow aplasia, complicated by mucositis and melena, intensified VWF/FVIII replacement and transfusion support were required. Following a switch to a concentrate with a higher VWF-to-FVIII ratio, improved haemostatic control was achieved. Poor platelet increments were associated with anti-HLA class I antibodies, indicating immune-mediated platelet refractoriness. Bleeding was controlled with twice-daily platelet transfusions, full-dose antifibrinolytic therapy, and VWF/FVIII replacement maintaining trough levels above 0.50 IU/ml. To our knowledge, this is the first reported case of auto-HSCT in a patient with a severe congenital bleeding disorder, highlighting the importance of individualized VWF/FVIII replacement and optimized transfusion support.