Hematologic Malignancies USMLE Step 1 Practice Question
A 63-year-old man presents with severe community-acquired pneumonia (BP 128/82, HR 108, RR 22, Temp 39.2°C, SpO2 94%). Laboratory studies reveal WBC 52,000/mm³ with left shift and toxic granulation; Döhle bodies noted on peripheral smear. Leukocyte alkaline phosphatase score is markedly elevated. Chest X-ray shows left lower lobe infiltrate. B symptoms absent. He denies prior chemotherapy. Which of the following best explains these hematologic findings?
Answer choices
- AHairy cell leukemia with marrow fibrosis
- BAcute promyelocytic leukemia due to t(15;17)
- CChronic myelogenous leukemia due to BCR-ABL fusion
- DReactive leukemoid reaction due to severe infectionCorrect answer
- EMyelodysplastic syndrome with pseudo-Pelger-Huet cells
- FChronic myelogenous leukemia with low LAP
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