Hematologic Malignancies USMLE Step 1 Practice Question
A 72-year-old man presents to the emergency department with a 3-day history of epistaxis, bleeding gums, and spontaneous bruising. He was started on warfarin 1 week ago for newly diagnosed atrial fibrillation. His wife notes he has been increasingly fatigued. Physical examination reveals petechiae on the lower extremities and oral mucosa. Vital signs: BP 138/86 mmHg, HR 105 bpm, RR 19/min, temperature 37.1°C. Laboratory studies show: WBC 145,000/μL with 82% circulating blasts, hemoglobin 7.5 g/dL, platelets 18,000/μL. Peripheral blood smear demonstrates numerous abnormal promyelocytes with abundant cytoplasmic granules and Auer rods. PT/INR is 1.2, aPTT is 32 seconds, fibrinogen is 380 mg/dL. Which of the following is the most likely diagnosis?
Answer choices
- AAcute myeloid leukemia with t(8;21)
- BWarfarin-induced disseminated intravascular coagulation
- CAcute promyelocytic leukemia with t(15;17)Correct answer
- DAcute lymphoblastic leukemia with high-risk features
- EChronic myeloid leukemia in accelerated phase
- FAcute myelomonocytic leukemia with normal coagulation studies
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