Anemias USMLE Step 1 Practice Question
A 31-year-old woman with systemic lupus erythematosus presents with dyspnea, chest pain, and confusion. Vital signs show BP 158/92 mmHg, HR 112/min, RR 22/min, temp 37.2°C, SpO2 98% on room air. Laboratory findings reveal hemoglobin 6.8 g/dL, platelets 45,000/μL, creatinine 2.1 mg/dL, and schistocytes on blood smear. Coagulation studies and fibrinogen are normal. Peripheral blood smear shows no spherocytes. She takes hydroxychloroquine. Which of the following is the most likely diagnosis?
Answer choices
- ALupus-induced thrombocytopenia
- BDisseminated intravascular coagulation
- CHemolytic uremic syndrome
- DAntiphospholipid syndrome
- EThrombotic thrombocytopenic purpuraCorrect answer
- FDrug-induced thrombocytopenia from hydroxychloroquine
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