An immunocompromised patient undergoing chemotherapy develops pancytopenia. Which mechanism explains why erythrocyte transfusions initially increase hemoglobin, but the reticulocyte count remains inappropriately low for the level of anemia?

💡 Explanation

Aplastic anemia results in bone marrow failure, leading to reduced production of all blood cells including reticulocytes, because chemotherapeutic agents suppress hematopoietic stem cells. Therefore, the reticulocyte count remains low despite transfusion, rather than reflecting iron deficiency, hemolysis, or erythropoietin resistance.

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