How can ferritin, serum iron, and total iron-binding capacity (TIBC) differentiate iron deficiency from anemia of inflammation?

How can ferritin, serum iron, and total iron-binding capacity (TIBC) differentiate iron deficiency from anemia of inflammation?

• A. Iron deficiency: low ferritin, low serum iron, high TIBC; anemia of inflammation: normal/high ferritin, low/normal iron, low or normal TIBC.
• B. Iron deficiency: high ferritin, high serum iron, low TIBC; anemia of inflammation: ferritin normal, iron low
• C. Iron deficiency: low ferritin, high serum iron, high TIBC; anemia of inflammation: high ferritin, low iron, low TIBC
• D. Iron deficiency: normal ferritin, normal iron, normal TIBC; anemia of inflammation: high ferritin, low iron, high TIBC

Answer: (A)

Differentiating these two conditions relies on what ferritin, serum iron, and TIBC reveal about iron stores, circulating iron, and transferrin availability. In iron deficiency, stores are depleted, so ferritin is low. With limited iron in the body, serum iron is also low, and the body increases transferrin production to capture more iron, which raises TIBC. In anemia of inflammation, iron is not primarily missing but being sequestered; ferritin tends to be normal or high because it is an acute-phase reactant, serum iron is low due to iron sequestration, and TIBC is low or normal because inflammation reduces transferrin production. So the pattern of low ferritin, low serum iron, and high TIBC fits iron deficiency, while normal or high ferritin with low serum iron and low/normal TIBC fits anemia of inflammation.

Differentiating these two conditions relies on what ferritin, serum iron, and TIBC reveal about iron stores, circulating iron, and transferrin availability. In iron deficiency, stores are depleted, so ferritin is low. With limited iron in the body, serum iron is also low, and the body increases transferrin production to capture more iron, which raises TIBC. In anemia of inflammation, iron is not primarily missing but being sequestered; ferritin tends to be normal or high because it is an acute-phase reactant, serum iron is low due to iron sequestration, and TIBC is low or normal because inflammation reduces transferrin production. So the pattern of low ferritin, low serum iron, and high TIBC fits iron deficiency, while normal or high ferritin with low serum iron and low/normal TIBC fits anemia of inflammation.