Measurement of total iron binding capacity is used in the differential diagnosis of anemia and in the control of chronic conditions of iron overload such as hereditary hemochromatosis. Also, the measurement of total iron binding capacity is an important indicator of the nutritional status of iron in the body.
Iron is an essential element for many processes in the body, including oxygen transport to tissues, for hemoglobin and myoglobin transporting oxygen chromoproteins, and for enzymes such as xanthine oxidase and peroxidase. Transferrin is an iron-carrying plasma protein (also called ironophylline), formed in the liver and has a half-life of 7-10 days. Transferrin is capable of binding more than its weight to iron (1 g of transferrin can carry 1.43 g of iron). In normal patients, saturation of iron transferrin is between 20% and 45%. Saturation of iron transferrin fluctuates daily, with a peak in the morning and a low point in the early evening.
Total Iron Binding Capacity (TIBC) is the maximum amount of iron that can be bound to transferrin.
In this assay, iron is added to the patient's serum (in vitro) until all transferrin binding sites are iron bound. Then, the excess iron is removed and the total amount of residual (bound) iron is measured, giving an assessment of the ability of transferrin to bind iron.
Possible Interpretations of Pathological Values
- Increase: Iron deficiency anemia, pregnancy. Medications: Iron salts, oral contraceptives.
- Decrease: Cirrhosis, dysmenorrhea, hemochromatosis, bleeding, hepatitis, hypothyroidism, kwashiorkor, chronic anemia, myocardial infarction, neoplasm, nephrosis, pernicious anemia, thalassemia, uremia. Medications: ACTH, asparaginase, chloramphenicol, corticotropin, cortisone, dextran, steroids, testosterone.
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. Correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.