Vascular pseudohemophilia, also known as von Willebrand disease (vWD), is an autosomal dominant or recessive inherited bleeding disorder that can affect both males and females, with transmission possible from either parent. The disease is caused by abnormalities in the quantity and quality of the vascular pseudohemophilia factor (Ⅷ:vMF) and von Willebrand factor antigen (vWF:Ag) within the high molecular weight portion of factor Ⅷ. In some patients, factor Ⅷ:C levels may also be reduced. When vWF is deficient, it affects platelet adhesion to the subendothelial tissue and the aggregation response of platelets to ristocetin. These functional abnormalities lead to bleeding symptoms.

bubble_chart Clinical Manifestations

From an early age, there may be recurrent epistaxis, gingival bleeding, gastrointestinal bleeding, hematuria, and skin bruising. Joint and intracranial bleeding are rare. Older girls often experience hypermenorrhea. Prolonged bleeding is common after trauma or tooth extraction.

bubble_chart Auxiliary Examination

1. Coagulation tests: Prolonged bleeding time, positive aspirin tolerance test. Normal or prolonged clotting time, prolonged APTT.
2. Platelet function tests: Decreased or normal platelet adhesion rate. Platelet aggregation test shows no aggregation with ristocetin, but can be corrected by normal human plasma (containing vWF).
3. Factor VIII assay: Plasma factor VIII:C decreased or normal, vWF:Ag decreased or normal. Platelet function defect diseases must be excluded.

bubble_chart Treatment Measures

1. Alternative Therapy: In cases of persistent bleeding or during surgery, fresh frozen plasma should be transfused at a dose of 10 ml/(kg·d), administered once daily or every other day (the biological half-life of vWF is 36 hours). Frozen plasma can also be used. Factor VIII concentrates contain fewer high-molecular-weight vWF multimers and are generally not the first-choice preparation.
2. DDAVP (1-desamino-8-D-arginine vasopressin): This drug promotes the release of factor VIII attached to blood vessel walls into the circulation, thereby achieving hemostasis. The dose is 0.2–0.4 μg/kg per administration, diluted in normal saline and infused slowly (>10–15 minutes). During the first 2–4 days, it should be administered every 8–12 hours.
3. Fibrinolytic Inhibitors: Tranexamic acid and aminomethylbenzoic acid can reduce mucosal bleeding.
4. Others: Avoid drugs such as aspirin, dipyridamole, indomethacin, prostaglandin F, and dextran, as they may affect platelet function and trigger bleeding. Local compression can be applied for hemostasis. For persistent epistaxis, gauze soaked in thrombin, fresh blood, or plasma can be used for packing.