In following patients with anemia, what do the lab values for iron, ferritin, transferrin, and TIBC (total iron binding capacity) tell me? — Ruth C. Gholz, RN, MS, AOCN, and colleagues at the Cincinnati VA Medical Center

As a single value, serum iron tells little about the total body iron status. Using this test in conjunction with the TIBC or transferrin level is helpful in determining the cause of anemia. Ferritin is a protein complex that serves as stored iron in both complex and noncomplex living organisms. The TIBC is similar to transferrin in that they both reflect the protein that is responsible for binding iron and transporting it to cells or places of storage. The higher they are, the more likely iron is deficient. It’s important to note that if ferritin is reduced, a patient has iron deficiency anemia until proven otherwise. — Donald Fleming, MD