Incidence and risk factors for life-threatening bleeding after allogeneic stem cell transplant.

Bleeding is a frequent complication after allogeneic haematopoietic stem cell transplantation (HSCT) and may affect survival. The purpose of this study was to determine the incidence and risk factors for life-threatening bleeding after HSCT by retrospective evaluation of 491 allogeneic HSCT recipients. With a median follow-up of 33 months, 126 out of 491 allogeneic HSCT recipients experienced a haemorrhagic event (25·7%) and 46 patients developed a life-threatening bleeding episode (9·4%). Pulmonary and gastrointestinal bleeding were the most common sites for life-threatening bleeding, followed by central nervous system. In multivariate analyses, the presence of severe thrombocytopenia after day +28 and the development of grade III-IV acute graft-versus-host disease (GVHD) or thrombotic microangiopathy (TMA) retained their association with life-threatening bleeding events. The overall survival at 3 years among patients without bleeding was 67·1% for only 17·1% for patients with life-threatening bleeding (P < 0·001). In conclusion, life-threatening bleeding is a common complication after allogeneic HSCT. Prolonged severe thrombocytopenia, acute grade III-IV GVHD and TMA were associated with its development.