Which of the following bleeding tests is abnormal in patients with von Willebrand disease?
A) Prolonged bleeding time
B) Thrombocytopenia
C) Prolonged prothrombin time
D) Shortened partial thromboplastin time
E) Increased levels of factor VIII in plasma

Question

Quizplus · Accepted Answer

A deficiency of the von Willebrand factor (vWF) in this disease, which carries the same name, affects the ability of platelets to participate in hemostasis. The bleeding time, which was designed to measure the function of platelets and blood vessels, is thus prolonged. Because vWF interacts with factor VIII, partial thromboplastin time is also prolonged and the concentration of factor VIII in blood is reduced.

Which of the Following Bleeding Tests Is Abnormal in Patients