Preparative leukapheresis impairs autologous donor hemostasis and platelet function.

BACKGROUND: Preparative apheresis is performed to produce blood or stem cell products. A rare but serious complication is bleeding due to the inherent loss of platelets and coagulation factors. OBJECTIVES: The aim of this study was to provide a comprehensive analysis of hemostasis in autologous donors undergoing preparative apheresis and to assess bleeding complications in this cohort. METHODS: In this prospective observational study, a large panel of cellular components and coagulation factors was quantified both immediately before and after apheresis of hematopoietic stem cells (n = 50) and lymphocytes (n = 29) for autologous cellular therapies. RESULTS: Postapheresis, we observed a small decrease (5.9%) in prothrombin time, while international normalized ratio, partial thromboplastin time, and thrombin time remained unaffected. Single component analysis revealed a median loss of factor (F)XIII of 15%, fibrinogen of 17.9%, antithrombin of 13.9%, von Willebrand factor (VWF) antigen of 18.7% and VWF activity of 18.2%. In terms of cellular components, we found a median reduction of 25.6% in platelet count, 19.4% reduction in leukocyte count, and 7.1% in hemoglobin level. Platelet aggregation after stimulation with arachidonic acid, adenosine diphosphate, and thrombin-activated peptide-6 was reduced. One patient (1.3%) with evident FXIII deficiency developed minor bleeding and required surgical intervention. CONCLUSION: Our analysis shows that hemostasis and platelet function are compromised after apheresis in autologous donors, despite mostly unaltered global coagulation parameters. These findings may be of value in the clinical management of apheresis, particularly regarding procedure-related bleeding events.