Coagulation Disorders USMLE Step 1 Practice Question
A 6-year-old boy with a family history of bleeding disorders presents with epistaxis and excessive bleeding after a minor laceration to his lip. Laboratory studies reveal a normal PT, prolonged aPTT, and normal platelet count. A factor assay shows 35% factor VIII activity. Which of the following is the most likely diagnosis?
Answer choices
- AHemophilia B
- Bvon Willebrand disease
- CFactor V deficiency
- DVitamin K deficiency
- EHemophilia ACorrect answer
- FFactor XI deficiency
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