Coagulation Disorders USMLE Step 1 Practice Question
A 7-year-old boy is brought to the emergency department because of swelling and severe pain in his right knee after a minor fall. His maternal uncle had similar problems. Examination shows a warm, tense knee with limited range of motion. Laboratory studies show normal platelet count, normal PT, and prolonged PTT. Which of the following is the most likely diagnosis?
Answer choices
- AImmune thrombocytopenia
- Bvon Willebrand disease
- CFactor VII deficiency
- DHemophilia ACorrect answer
- EGlanzmann thrombasthenia
- FHemophilia B from factor IX deficiency
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