Coagulation Disorders USMLE Step 1 Practice Question
A 34-year-old woman presents to the emergency department with severe vaginal bleeding and easy bruising. Laboratory studies show PT 18 seconds (normal 11-13), aPTT 45 seconds (normal 25-35), platelet count 450,000/μL, and fibrinogen 85 mg/dL (normal 200-400). She denies family history of bleeding disorders. Which of the following is the most likely diagnosis?
Answer choices
- AThrombotic thrombocytopenic purpura
- BVon Willebrand disease
- CVitamin K deficiency
- DHemophilia A
- EDisseminated intravascular coagulationCorrect answer
- FFactor V inhibitor
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