TIBC

Latest Edit: Hector 2014-03-21 (EDT)

See Also	Lab Tests

TIBC, or total iron-binding capacity is a measurement of all proteins available for binding mobile iron.

Discussion

• Transferrin represents the largest quantity of iron-binding proteins.
• TIBC is therefore an indirect, yet accurate measurement of transferrin.
• TIBC is measured by adding excess iron to the patient's serum. This causes transferrin to become saturated and excess iron is removed. The remaining iron is then measured.
• Ferritin is not included in TIBC because it binds only stored iron.

Patient Preparation

• No fasting required.

• Factors which can cause increased levels

• Drug: fluorides and oral contraceptives

• Factors which can cause decreased levels

• Drugs: ACTH and chloramphenicol

Clinical Implications

High levels indicate:

• Estrogen therapy
• Pregnancy (late)
• Polycythemia vera
• Iron deficiency anemia

Low levels indicate:

• Malnutrition
• Hypoproteinemia
• Inflammatory diseases
• Cirrhosis
• Hemolytic anemia
• Pernicious anemia
• Sickle cell anemia

Associated Tests

• Ferritin