Key benefits of the Randox sTfR assay

Ordering information

(L) Indicates liquid option

Clinical Significance

The most common nutritional deficiency globally is iron deficiency (ID) with 15% to 20% of the global population affected by IDA ¹. IDA has also been recognised as the most common form of anaemia in infants aged between 4 and 24 months of age, school-age children, female adolescents, pregnant women, and nurturing mothers. It has been recognised that young children including infants require high levels of iron during growth periods making them more susceptible to ID ².

Soluble transferrin receptor levels have also been found to be a strong biomarker of erythropoietic and haemolysis drive compared to iron-restricted erythropoiesis in paediatric sickle cell disease ³.

Another study found that elevated levels of sTfR is linked with central obesity in men with hyperferritinemia ⁴.

sTfR has also “been included in multivariable blood testing models for the detection of performance enhancing erythropoietin misuse in sport” and has been recommended as a marker of ID in athletes ⁵.

Biological Significance

A truncated extracellular form of the membrane transferrin receptor, soluble transferrin receptor (sTfR) is a marker of iron status and erythropoiesis. sTfR levels have been found to increase in iron-deficient erythropoiesis and iron deficiency anaemia (IDA). Some have reported that sTfR is useful in the differential diagnosis of IDA and anaemia of chronic disease or inflammation (ACD) ¹.

Completing your anaemia toolbox

At present, ferritin remains the traditional iron deficiency marker with serum ferritin reflecting intracellular iron storage. Ferritin is an acute phase reactant, and so ferritin levels can be influenced by inflammatory conditions. In the presence of inflammation, ferritin levels may be represented as an elevated value leading to a false representation of iron stores in the body, resulting in a delayed diagnosis. For these reasons, sTfR should be tested when the reliability of a ferritin test is compromised.

There isn't a single diagnostic test to diagnose anaemia. Currently the diagnosis comprises of two steps:

> Firstly confirming that the patient has anaemia which utilises the haemoglobin assay and red blood cell count.

> Secondly is the determination of the root cause of the anaemia which can be identified through testing sTfR and transferrin levels.

Randox offer a number of diagnostic reagents in addition to sTfR which can be used on a wide range of biochemistry analysers for the diagnosis of anaemia. The Randox assays have shown clinical utility in testing for anaemia. The Randox anaemia toolbox comprises of: iron, ferritin, transferrin, unsaturated iron binding capacity (UIBC), total iron binding capacity (TIBC) and the recent addition of sTfR.

There are many different types of anaemia and many triggers and conditions which contribute to the development of anaemia. For this reason, a single test cannot diagnose an individual with anaemia while also knowing what the root cause of it is. Additionally, patient symptoms can give an indication but a full range of diagnostic tests provide independent information to aid the definitive medical diagnosis and enable clinicians to provide effective treatment for patients.