Content :
◉ What is transferrin blood test?
Transferrin is a glycoprotein mainly produced by the liver and then secreted into the plasma. Its primary function is to transport iron from sites of absorption to sites of hemoglobin utilization, storage, and breakdown.
A transferrin test is a test that measures the level of transferrin in your blood, which helps your doctor get more information about the iron balance in your body (deficiency or overload).
This test is usually ordered when anemia is suspected and should be interpreted in conjunction with other tests and clinical symptoms.
◉ What is transferrin
Transferrin is a plasma iron transport protein that mediates iron exchange between tissues. It is not lost in delivering iron to the cells but returns to the plasma and is reused.
This glycoprotein is capable of binding up to two iron atoms (Fe3+) with high affinity. To enter cells that use iron, transferrin binds to a cell surface receptor called R-Tf.
After transferrin binding, the R-Tf-transferrin-iron complex enters the cell through a phenomenon called endocytosis.
The amount of iron that can be bound to transferrin, added to the iron already bound, represents the total iron binding capacity (TIBC). The ratio of serum iron level to TIBC represents the transferrin saturation coefficient.
◉ What is the importance of transferrin blood test?
This laboratory test provides important information about iron metabolism and can serve several purposes in clinical practice such as:
- Iron Status Assessment: The transferrin test helps evaluate a person's iron status.
- Anemia Evaluation: Transferrin measurements are often used alongside other iron-related tests to help diagnose and differentiate various types of anemia.
- Liver Function Assessment: Since transferrin is primarily synthesized by the liver, the transferrin test can provide insights into liver function.
- Nutritional Assessment: Transferrin levels can be influenced by nutritional factors, such as protein malnutrition and chronic liver disease-related malnutrition.
◉ How can I prepare for the test?
Preparation for a transferrin test is generally straightforward. Here are some general guidelines to help you prepare for the test:
- Fasting: In most cases, fasting is not required for a transferrin test.
- Medications and Supplements: Inform your healthcare provider about any medications, supplements, or herbal remedies you are taking, as they may affect the test results.
- Timing: The transferrin test is typically a routine blood test that can be performed at any time during the day.
- Hydration: It's generally recommended to stay well-hydrated before the blood test. Drinking water can help make it easier to collect a blood sample.
Note: Specific preparation instructions may vary depending on your individual situation and the instructions given by your healthcare professional.
◉ Normal range of transferrin test
The normal range of the transferrin test depends on the method of measurement and the unit of measurement.
The normal vlaue of the transferrin test is:
- For adults: 200 to 400 mg/dL.
- For infants: The range can be around 100 to 200 mg/dL.
◉ High levels of transferrin
1. Causes of high transferrin levels
1- The most common cause of high transferrin is iron deficiency. When iron levels decrease, the body increases transferrin production to transport more iron from absorption sites, like the intestine, to the tissues and organs that require it, thus maintaining iron balance in the body.
This situation may be observed in situation such as:
- Iron-deficiency anemia.
- Dietary deficiency.
- Chronic bleeding (e.g., ulcers),
- Gut disorders that decrease iron absorption.
- Exposure to toxins (e.g., lead).
2- An increase in transferrin levels may also be observed in cases of estrogen impregnation, such as when taking estrogen-containing oral contraceptives or during the 2nd and 3rd trimesters of pregnancy .
3- Certain diuretic drugs.
2. Symptoms of high transferrin levels
- Fatigue.
- Weakness.
- Pale skin
- Shortness of breath
- Dizziness
- Headache
- Cold hands and feet
- Brittle nails
- Chest pain
- Irregular heartbeat
◉ Low levels of transferrin
◉ 1. Causes of low transferrin levels
Low transferrin in plasma indicates:
- Iron overload, which means the binding site of transferrin, is highly saturated with iron. Iron overload suggests hemochromatosis, which will lead to the deposition of iron on tissues.
- Liver damage leading to reduced production of transferrin.
- Excessive protein leaks which can be of renal, gastrointestinal or cutaneous (burns) origin.
- Atransferrinemia: A genetic mutation resulting in the absence of transferrin, which leads to hemosiderosis in the heart and liver, which can lead to heart and liver failure.
- Hemolytic anemia (may be normal or low).
- Acute or chronic inflammatory syndromes.
◉ 2. Symptoms of low transferrin levels
- Abdominal pain
- Joint pain
- Fatigue
- Weakness
- Weight loss
- Loss of libido
- Diabetes
- Liver problems
- Heart problems
- Skin discoloration
◉ Additional tests
- A CBC blood test: is a test that counts the cells that make up your blood: red blood cells, white blood cells, and platelets.
- Total iron-binding capacity (TIBC): This test measures the total amount of iron that can be bound by transferrin and other proteins in the blood. It is an indirect measure of transferrin level.
- Unsaturated iron-binding capacity (UIBC): This test measures the amount of iron that is not bound by transferrin and other proteins in the blood. It is calculated by subtracting serum iron from TIBC.
- Transferrin saturation: This test measures the percentage of transferrin that is bound by iron. It is calculated by dividing serum iron by TIBC and multiplying by 100.
- Ferritin: This test measures the amount of ferritin, a protein that stores iron in the tissues, in the blood. It reflects the total amount of iron stored in the body.
- Iron : is a blood test that measures different substances related to iron in your body.
◉ Conclusion
In summary, the transferrin blood test is a valuable tool for evaluating iron status and diagnosing certain medical conditions related to iron metabolism. It provides important information about transferrin levels and iron-binding capacity in the blood. However, it should be interpreted in conjunction with other clinical information and additional laboratory tests to ensure accurate diagnosis and appropriate management of iron-related disorders.