Measurement of serum saturation of transferrin is used to control the state of iron in the body, whether overload or deficiency.
Transferrin, or otherwise, siderophyllin, belongs to the beta globulins and is a glycoprotein with a relatively short (about 7 days) half-life. It is formed in the liver and transports iron from the intestinal mucosa to iron storage sites and hemoglobin synthesis sites (bone, muscle, erythrocytes, lymphocytes). Transferrin allows the transfer of iron by binding to the transferrin receptors.
Transferrin is capable of binding more than its weight to iron (1 g of transferrin can carry 1.43 g of iron). Normally, iron saturation (transferrin saturation) is between 20% and 45%. Due to the short half-life, its values decrease more rapidly in malnutrition than albumin.
Transferrin saturation is calculated based on serum iron concentration and total iron binding capacity (TIBC). In cases of iron deficiency, the degree of transferrin saturation appears to be an extremely sensitive indicator of functional iron depletion. In controlling hereditary hemochromatosis, saturation of transferrin provides a better indication of the homozygous genotype than ferritin. Treatment of erythropoietin anemia in patients with renal impairment is effective only when sufficient iron stores are available and the best monitoring of treatment is performed by determining transferrin saturation. Determination of transferrin saturation in combination with ferritin measurement gives very important information on iron overload in patients with chronic liver disease.
Possible Interpretations of Pathological Values
- Increase: Hemochromatosis, hemodialysis, thalassemia
- Decrease: Iron anemia, neoplasms, rheumatoid arthritis, uremia
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.