In von Willebrands disease there is:
Von Willebrand disease (VWD) - - Autosomal dominant disorder - The main source of plasma von-Willebrand factor is endothelial cells. - vWF circulates in the plasma in association with factor VIII. - Patients with VWD have defects in platelet function despite a normal platelet count - Deficiency of von willebrand factor (VWF -promote platelet adherence and activation) causes | platelet adhesion ( |BT) and | Intrinsic pathway activity ( | aPTT) . - von willebrand factor can also be found in : Platelet granules Subendothelium Endothelial cells within cytoplasmic vesicles called Weibel-Palade bodies C/F Spontaneous mucosal bleeding - Petechiae /purpura /epistaxis / melena excessive bleeding from wounds menorrhagia Lab findings - Platelet count - Normal Prothrombin time - Normal Bleeding time - Increased Activated paial thromboplastin time (aPTT)-Increased Rx - Desmopressin for mild form - Cryoprecipitate for severe form
Isolated prolonged PTT with normal PT
Normal PTT with normal PT
Prolongation of both PT and PTT
Prolongation of thrombin time
Bleeding disorder