What is a characteristic finding in the iron studies of iron deficiency anemia?

In iron deficiency anemia, a characteristic finding is increased total iron binding capacity (TIBC). This occurs because, in response to low serum iron levels, the liver increases the production of transferrin, the protein responsible for transporting iron in the bloodstream. Since there is insufficient iron available to saturate transferrin, the total iron binding capacity rises.

In contrast, the other components of iron studies typically reveal low serum iron and low ferritin levels in iron deficiency anemia. Ferritin, which reflects the body's stored iron, is decreased due to the depletion of iron stores. The transferrin receptor levels typically increase when iron levels are low, indicating a heightened demand for iron at the cellular level. Therefore, the elevation of TIBC is a key laboratory finding that supports the diagnosis of iron deficiency anemia, distinguishing it from other types of anemia.