The
bleeding tendency in
von Willebrand disease (VWD) is heterogeneous and some patients with the mildest form of the disease have no significant
bleeding symptoms throughout their lives. In some cases, the most difficult task for a clinician is to decide whether any treatment is actually required. However, cases with moderate to severe
factor VIII (FVIII) and
von Willebrand factor (VWF) deficiency usually require treatment to stop or prevent
bleeding. Increasing autologous FVIII/VWF by
desmopressin administration or providing normal allogeneic VWF through the infusion of plasma-derived concentrates can correct FVIII and VWF deficiencies and normalize or shorten bleeding time (BT). FVIII levels are the best predictors of soft tissue or surgical
bleeding, while BT normalization, reflecting the correction of platelet-dependent functions of VWF, is considered a reliable
indicator of an effective treatment of mucosal
bleeding. Recombinant concentrates of FVIII are not indicated (apart from cases with
alloantibodies against exogenous VWF), since they are devoid of VWF and lack its stabilizing effect on circulating FVIII. A very-high-purity concentrate of VWF has recently been made available, but its advantages over conventional concentrates containing both FVIII and VWF moieties are not obvious. The best way to select the appropriate treatment is to perform a test infusion with
desmopressin in any patient with clinically significant VWD, provided that he/she has no
contraindication to the compound or belongs to subtype with an anticipated lack of response (for example,
type 3 VWD with FVIII/VWF lower than 5%).