- What is it for
- What is Transferrin Saturation Index
- What high transferrin means
- What low transferrin means
Transferrin is a protein mainly produced by the liver and its main function is to transport iron to the marrow, spleen, liver and muscles, maintaining the proper functioning of the body.
The normal values of transferrin in the blood are:
- Men: 215 - 365 mg / dL Women: 250 - 380 mg / dL
The evaluation of the transferrin concentration in the blood should be done in an 8 to 12 hour fast, depending on the doctor's and laboratory's guidance, and is usually requested together with the iron and ferritin dosage, in addition to biochemical and hematological tests, such as the blood count, for example, should be interpreted together. Know what the blood count is for and how to interpret it.
What is it for
The transferrin dosage is usually requested by the doctor to make the differential diagnosis of microcytic anemias, which are those characterized by the presence of red blood cells smaller than normal. Thus, in addition to transferrin, the doctor requests the measurement of serum iron and ferritin. Learn more about ferritin.
The laboratory profile of microcytic anemias is:
| Serum iron | Transferrin | Transferrin saturation | Ferritin | |
| Iron deficiency anemia | Low | High | Low | Low |
| Chronic Disease Anemia | Low | Low | Low | Normal or increased |
| Thalassemia | Normal or increased | Normal or decreased | Normal or increased | Normal or increased |
| Sideroblastic anemia | High | Normal or decreased | High | High |
In addition to these tests, hemoglobin electrophoresis may be requested in order to identify the patient's type of hemoglobin and thus confirm the diagnosis of thalassemia, for example.
It is important that the results of the tests are interpreted by the doctor, because in addition to the concentration of iron, transferrin and ferritin, it is necessary to analyze other tests so that it is possible to check the general clinical condition of the patient.
What is Transferrin Saturation Index
The Transferrin Saturation Index corresponds to the percentage of transferrin that is occupied by iron. Under normal conditions, 20 to 50% of transferrin binding sites are occupied with iron.
In the case of iron deficiency anemia, for example, the transferrin saturation index is low due to the low concentration of iron available in the blood. That is, the organism starts to produce more transferrin in an attempt to capture as much iron as possible to take to the tissues, but each transferrin carries less iron than it should.
What high transferrin means
High transferrin is usually seen in iron deficiency anemia, known as iron deficiency anemia, in pregnancy and in treatment with hormone replacement, especially estrogen.
What low transferrin means
Low transferrin can happen in some situations, such as:
- Thalassemia; Sideroblastic anemia; Inflammation; Situations in which there is loss of proteins, such as chronic infections and burns, for example; Liver and kidney diseases; Neoplasms; Nephrosis; Malnutrition.
In addition, the concentration of transferrin in the blood may also be decreased in anemia of chronic disease, which is a type of anemia that normally occurs in hospitalized people and who have chronic infectious diseases, inflammations or neoplasms.
