What lab value is increased in iron deficiency anemia?

In iron deficiency anemia, there is an increase in Total Iron-Binding Capacity (TIBC). This value reflects the body's attempt to transport more iron due to a deficiency. When there is insufficient iron available in the body, the liver produces more transferrin, which is the protein that carries iron in the bloodstream. Consequently, higher levels of transferrin lead to an elevated TIBC.

Ferritin, on the other hand, typically shows decreased levels in iron deficiency anemia because ferritin is a storage protein for iron, and its levels decrease when there is inadequate iron available to store. Vitamin B12 levels are not directly related to iron deficiency; they are often assessed separately in the context of anemia, particularly macrocytic anemia, which is distinct from iron deficiency anemia.

Understanding these nuances helps in distinguishing between different types of anemia and understanding the underlying mechanisms.