Question 150

Question:

A 18-year-old woman presents with menorrhagia over the last several years, although her menses “have always been heavy.” On further questioning, she reports having easy bruising for as long as she can remember, and that her mother also bruises easily. Which of the following is the most likely cause of her symptoms?

Correct Answer: E.  Von Willebrand’s disease

Defects in Von Willebrand factor (E) can cause platelet abnormalities as well as a decreased amount of circulating factor VIII, and thus lead to the manifestations of ‘superficial’ bleeding (bruising, heavy menses, nosebleeds, etc). Von Willebrand disease is also the most common hereditary bleeding disorder.
Factor V Leiden (A) causes a hypercoagulable state. The Leiden variant of factor V cannot be inactivated by activated protein C. A deep vein thrombosis or pulmonary embolism question would be a common clinical scenario seen in a Step 1 question.
The lupus anticoagulant (B) is named such because it causes a prolongation of the PTT in vitro, but leads to hypercoaguability in vivo. It is associated with anti-phospholipid syndrome.
Hemophilia A (C) is an X-linked deficiency in factor VIII, resulting in bleeding. It is easily differentiated from Von Willebrand’s disease because (1) it almost exclusively occurs in boys as it is X-linked, (2) it is more severe and will present during childhood, and (3) the bleeding is ‘deep’ (i.e. internally, as in joints or internal organs) as opposed to ‘superficial.’
Protein C deficiency (D) is not associated with bleeding, but with hypercoagulability, due to and inability to inactivate factor V.