A 65 year-old man presents to the emergency department with a one-week history of bilateral upper extremity swelling and ecchymoses. He had gone to bed 8 days ago feeling well, but was symptomatic upon awakening. He went to an outside hospital emergency department where he was briefly evaluated and promptly discharged. The swelling and bruising subsequently progressed, and so he sought care at your hospital. His only relevant past medical history is peptic ulcer disease. He has never had surgery. He has no family history of bleeding, easy bruising or coagulopathy. He smokes a half-pack of cigarettes per day and drinks 1-2 beers each day. He works in construction. He takes over-the-counter vitamin supplements, and has no known allergies to medications.