Bleeding matters Perspectives on the clinical phenotype and management of hemophilia

Hemophilia A and B are X-linked inherited coagulation disorders that are caused by a deficiency in coagulation factor VIII or IX, respectively. As a consequence, persons with hemophilia have an increased bleeding tendency. The most characteristic symptoms of hemophilia include bleeds into the joints and muscles, which may result in disabling and irreversible joint damage. A rare but potentially devastating complication in hemophilia is the occurrence of intracranial hemorrhage. While the clinical picture is extensively studied in severe hemophilia, information on the bleeding phenotype and optimal management in non-severe hemophilia remains limited. This thesis contributes knowledge on the clinical phenotype, treatment and management of hemophilia, with a specific focus on non-severe hemophilia. These findings may guide expectations and education for persons with non-severe hemophilia, as well as for persons with severe hemophilia treated on novel products in whom the phenotype is converted into that of mild hemophilia. Priorities in research and care that are identified in this thesis include the high incidence of intracranial hemorrhage, the presence of joint changes in non-severe hemophilia and a potential suboptimal use of desmopressin treatment.