A patient develops severe B12 deficiency due to autoimmune destruction of parietal cells in the stomach, leading to intrinsic factor absence. Which outcome affecting erythropoiesis becomes most likely?

💡 Explanation

B12 deficiency impairs DNA synthesis in developing red blood cells. Because intrinsic factor is required for B12 absorption, its absence results in ineffective erythropoiesis, therefore megaloblastic anemia develops, rather than increased reticulocyte production, which would occur in hemolytic anemia.

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