Anemias USMLE Step 1 Practice Question
A 37-year-old woman with iron deficiency anemia (hemoglobin 6.2 g/dL) receives a packed red blood cell transfusion. Thirty minutes later, she develops fever (38.9°C), chills, and tachycardia (HR 105/min) but remains normotensive (BP 128/82 mmHg) with oxygen saturation of 97% on room air. She denies flank pain and urinalysis shows no hemoglobinuria. Direct antiglobulin test is negative. Which of the following is the most likely explanation?
Answer choices
- ACytokines released from donor leukocytes during storageCorrect answer
- BImmediate complement mediated ABO incompatibility
- CPulmonary capillary leak due to donor anti leukocyte antibodies
- DType I hypersensitivity reaction to donor IgA in a patient with normal IgA levels
- EMassive hemolysis due to glucose 6 phosphate dehydrogenase deficiency
- FAcute hemolytic transfusion reaction
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