BackATTENTION, PROMOTION! By ordering the "ferritin" analysis, you will receive a free "soluble transferrin receptor" test as a gift
Anemia is a condition characterized by a decrease in the amount of hemoglobin. Often, anemia is not an independent disease, but a manifestation of some other disease. In this case, the tactics of treatment will differ significantly. Laboratory diagnostics help to understand the cause of anemia, namely "soluble transferrin receptors".
For all those who need the most accurate diagnosis of anemia, the OLYMP CDL presents the "soluble transferrin receptors" test*
*The promotion is valid when ordering the ferritin analysis. The promotion is limited in duration. For the interpretation of the results of the examination, it is necessary to consult a doctor. Find out more by phone in your city.
SOLUBLE TRANSFERRIN RECEPTORS
Anemia is not only an independent nosological unit, but also the first sign of some gastrointestinal diseases. It is customary to estimate iron stores with the help of ferritin, but this is often hampered by concomitant pathologies that distort the value of ferritin. The only reliable indicator of true iron levels is bone marrow, but it is difficult to examine. In this regard, the index of the ratio of soluble receptors to transferrin and ferritin (sTfR-SF index) has been developed as the equivalent of a bone marrow study. Many scientific studies confirm the high specificity and sensitivity of the method [1,2,3].
Soluble transferrin receptors (sTfR) are polypeptides located on cell membranes that provide active transport of iron ions into the cell. Some of the receptors are dissolved in the blood. As the body's need for iron increases, more and more receptors are located on the surface of cells, while some of the receptors are "split" from the cell under the action of extracellular proteases and circulate in the bloodstream.
The concentration of sTfR correlates with the level of transferrin: with a decrease in the concentration of serum iron, there is an increase in both sTfR and transferrin, but the level of sTfR does not depend on inflammatory processes, the state of hepatocytes and the hormonal background of the patient.
The use of sTfR improves the clinical diagnosis of iron deficiency anemia, especially in the presence of coexisting chronic gastrointestinal disease or malignancies[1].
The index of the ratio of sTfR to ferritin due to the peculiarities of the units of measurement is calculated according to the formula:
The coefficient is relevant for sTfR and ferritin values outside the reference interval.
Table 1. Sensitivity of markers of iron deficiency anemia [2]
| Ferritin, % | sTfR, % | sTfR-SF index, % | |
|---|---|---|---|
| Sensitivity | 85 | 89 | 100 |
| Specificity | 63.9 | 80.6 | 80.6 |
| Positive Predictive Value | 75.5 | 85.7 | 87 |
| Negative Predictive Value | 76.7 | 85.3 | 100 |
| False positive result | 36.1 | 19.4 | 19.4 |
| False negative result | 14.9 | 10.6 | 0 |
| Accuracy | 75.9 | 85.54 | 91.57 |
Table 2. Sensitivity of anemia markers in chronic diseases [2]
| Ferritin, % | sTfR, % | sTfR-SF index, % | |
|---|---|---|---|
| Sensitivity | 81.8 | 84.8 | 84.8 |
| Specificity | 77.8 | 100 | 97.2 |
| Positive Predictive Value | 77.1 | 100 | 96.6 |
| Negative Predictive Value | 82.4 | 87.8 | 88 |
| False positive result | 22.2 | 0 | 2.8 |
| False negative result | 18.2 | 15.2 | 15.2 |
| Accuracy | 79.71 | 91.3 | 89.86 |
Indications for the test:
Assessment of the iron deficiency state of the body
Diagnosis of iron deficiency anemia and chronic diseases leading to changes in laboratory markers of anemia
High levels of ferritin
Interpretation:
Increased levels of soluble transferrin receptors
Iron deficiency in the body
Enhancement of erythropoiesis
Decreased levels of soluble transferrin receptors:
Anemia as a result of other pathologies
Interpretation of the sTfR-ferritin ratio index [2]
An index of more than 0.7 is an iron deficiency in the body
Index less than 0.5 is anemia as a result of other pathologies
1. J Gastrointestin Liver Dis. 2009 Sep;18(3):345-52. Soluble transferrin receptors and iron deficiency, a step beyond ferritin. A systematic review. PMID: 19795030
2. J Ayub Med Coll Abbottabad. 2011 Jul-Sep;23(3):44-6. Serum transferrin receptor, serum ferritin and serum transferrin receptor-ferritin index in adults with iron deficiency anaemia. PMID: 23272433
3. Scand J Clin Lab Invest. 2005;65(7):571-6. Usefulness of soluble transferrin receptor and ferritin in iron deficiency and chronic disease.
4. Annals of Gastroenterology (2011) 24, 108-114. Soluble transferrin receptor-ferritin index in the evaluation of anemia in inflammatory bowel disease: a case-control study
