Coagulation Disorders USMLE Step 1 Practice Question
A 41-year-old woman presents for preoperative clearance prior to elective hysterectomy. She reports no personal or family history of bleeding disorders. On review of systems, she denies easy bruising, spontaneous bleeding, or prolonged bleeding after minor dental work 2 years ago. Vital signs are stable. Laboratory evaluation reveals: PT: 18 seconds (normal 11-13.5 seconds)
aPTT: 52 seconds (normal 25-35 seconds)
Thrombin time: 12 seconds (normal 11-13.5 seconds)
Fibrinogen: 300 mg/dL (normal 200-400 mg/dL)
Platelet count: 250,000/μL (normal 150,000-400,000/μL)
Factor V activity: 25% (normal 70-130%)
Factor VIII activity: 22% (normal 70-130%)
Factor II, VII, X activities: 95%, 98%, 100% respectively She takes a daily multivitamin and denies alcohol use. Which of the following is the most likely diagnosis?
Answer choices
- AVitamin K deficiency
- BLiver cirrhosis with synthetic dysfunction
- CDisseminated intravascular coagulation
- DCombined factor V and VIII deficiency (SPCA deficiency)Correct answer
- EFactor V inhibitor with secondary hemophilia A
- FWarfarin therapy with supratherapeutic anticoagulation
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