Which anemia is most often linked to malabsorption or poor dietary intake of folate?

• A. Folate deficiency anemia
• B. Pernicious anemia
• C. Aplastic anemia
• D. Iron deficiency anemia

Answer: (A)

Folate deficiency anemia is the one most closely tied to inadequate folate intake or malabsorption. Folate is needed for thymidylate synthesis and DNA replication; without enough folate, erythroid precursors can’t mature properly, leading to megaloblastic (macrocytic) anemia. Because folate is absorbed mainly in the proximal small intestine, conditions that damage absorption (such as celiac disease, inflammatory bowel disease, tropical sprue, pancreatic insufficiency, or after certain surgeries) or chronic poor dietary intake (think alcoholism or malnutrition) readily cause this type of anemia. Blood cells become large and poorly formed, and the reticulocyte count is typically low because erythropoiesis is impaired. Supplementing folate improves the anemia if B12 status is adequate. In contrast, pernicious anemia is due to vitamin B12 deficiency from intrinsic factor loss (can also cause macrocytosis but has different underlying cause and potential neurologic symptoms), aplastic anemia is marrow failure with pancytopenia, and iron deficiency anemia is microcytic and due to iron shortage.