Incidence, Risk Factors, and Outcomes of BK Hemorrhagic Cystitis in Hematopoietic Stem Cell Transplantation From HLA-Matched and Haploidentical Donors With Post-Transplant Cyclophosphamide.

BK hemorrhagic cystitis (BK-HC) is a common complication following hematopoietic stem cell transplantation (HSCT), particularly when posttransplant cyclophosphamide (PTCy) is used as graft-versus-host disease (GVHD) prophylaxis. However, comparative studies of BK-HC incidence in matched sibling donors (MSD) and unrelated donors (MUD) often include small haploidentical (HAPLO) donor cohorts and usually lack detailed information on disease evolution, coinfections, management and impact on outcomes. This study aimed to evaluate the incidence, risk factors, and outcomes in patients with hematologic malignancies undergoing HSCT from MSD, MUD, HAPLO donors using PTCy as GVHD prophylaxis.