Coagulation Disorders USMLE Step 1 Practice Question
A 12-year-old girl has recurrent gingival bleeding and heavy menses. Her platelet count, PT, and PTT are normal, but bleeding time is prolonged. Platelet aggregation studies show absent aggregation in response to ADP, collagen, and epinephrine, with normal ristocetin response. Which of the following is the most likely cause of her disease?
Answer choices
- ADeficiency of vitamin K
- BDeficiency of GpIb
- CDeficiency of ADAMTS13
- DDeficiency of GpIIb/IIIaCorrect answer
- EDeficiency of factor IX
- FDeficiency of von Willebrand factor
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