A patient has microcytic anemia with low ferritin and high TIBC. What is the most likely diagnosis and first-line treatment?

• A. Folate deficiency; measure serum folate
• B. Iron deficiency anemia; IV iron therapy
• C. Iron deficiency anemia; oral iron supplementation and evaluation for ongoing blood loss
• D. Anemia of chronic disease; treat underlying disease

Answer: (D)

Pattern of iron studies guides the diagnosis. A microcytic anemia with low ferritin and high TIBC points to iron deficiency anemia, usually from ongoing blood loss or inadequate iron intake. The best first-line treatment is oral iron supplementation, paired with evaluating for ongoing blood loss so the underlying cause can be addressed. IV iron is reserved for cases where oral iron isn’t tolerated or absorption is poor, or when rapid correction is needed.

Why the other possibility doesn’t fit: folate deficiency causes macrocytic anemia, not microcytic, so measuring serum folate wouldn’t explain the iron-study pattern. anemia of chronic disease typically shows low iron with normal or high ferritin and low TIBC, not low ferritin with high TIBC, so treating the underlying chronic condition is the approach there, not iron repletion first.