Transferrin saturation

Transferrin Belonging to beta-globulins, it is synthesized mainly by parenchymal cells of the liver, in small quantities - in the central nervous system, ovaries, testicles and T-helper cells. The synthesis of transferrin depends on the functional state of the liver, the supply of iron in the body and the need for iron.

The main function of transferrin is to transport the absorbed iron in the intestine to its depots (liver, spleen), reticulocytes, and their precursors in the bone marrow.

Transferrin has two iron-binding sites, each of which binds to an iron ion (Fe3 +). Transferrin can also bind to other metal ions (zinc, cobalt, etc.).

Only 25-40% of the total amount of transferrin in the human body contains iron. With iron deficiency in the body and decreased levels of iron in the blood serum, the transferrin content increases. A change in these rates is one of the most important signs of iron deficiency anemia. Similar changes are observed during pregnancy and childhood, but they are less pronounced. The increase in transferrin concentration in these cases is associated with an increase in its synthesis to meet the increased needs of the body.

Compared to iron in the blood serum, transferrin levels are more stable and less dependent on sex, age, and daily changes.

In red blood cells in the spleen, liver, and bone marrow, iron released from heme is transported to the bone marrow via heme transferrin; The iron part is included in the composition of ferritin and hemosiderin.

One molecule of transferrin binds two iron atoms - Fe3 + ions, and 1 g of transferrin - about 1,25 mg of iron. The calculated value is used in diagnostics - Saturation of transferrin (saturation) with iron, which refers to the ratio of serum iron concentration to the maximum ability (percentage) of iron to bind by transferrin. The standard values ​​of transferrin saturation are - 20-55%. Decreased transfer of iron to saturated transferrin - A decrease in iron concentration and an increase in transferrin concentration indicate anemia due to iron deficiency. A saturation of less than 20% of transferrin is a sign of reduced iron supply to bone marrow erythrocyte precursors. With a significant increase in iron transfer of saturated transferrin in plasma, low-molecular-weight iron occurs, which can accumulate in the liver and pancreas and can cause their damage.

When should we test for transferrin saturation?

• Differential diagnostics of anemia;
• Evaluation of iron deficiency anemia, thalassemia, sideroblastic anemia;
• Diagnosis of iron overload and hemochromatosis.

The test can be scheduled when a person develops signs and symptoms of anemia, such as:

• Chronic fatigue;
• Dizziness;
• Weakness;
• headache;
• Pale skin;

Testing may be scheduled when there is a suspicion of iron overload. Signs and symptoms of iron overload are individual and worsen over time, they are caused by the accumulation of iron in the blood and tissues. Symptoms may include:

• Pain in the joints;
• Fatigue, weakness;
• Lose weight;
• Lack of energy;
• Stomach-ache;
• Decreased libido;
• Damage to organs such as the heart and / or liver.

How to prepare for the test?
The test should be performed on an empty stomach.

Research material

Venous blood

Possible interpretation of the results

Transferrin saturation increases:

• Iron deficiency anemia;
• Hemolytic anemia;
• Thalassemia;
• Iron excess syndromes, hemochromatosis;
• Iron intake;

Transferrin saturation decreases:

• Anemia in chronic diseases and infections (sometimes transferrin levels may be normal);
• Iron deficiency anemia.

Resources

https://spravochnik.synevo.ua/ru/diagnostica-anemii/transferrin.html

https://www.synevo.ro/shop/coeficientul-de-saturatie-a-transferinei/