Soluble Transferrin Receptor (sTfR)
Biochemistry Overview / Directory
Purpose of the test
Transferrin receptors are specific cell surface receptors that bind iron-transferrin complexes in the transport of iron in plasma. The number of cell surface TfR molecules reflects cellular iron requirement. Reduced iron supply results in up-regulation of TfR synthesis. The soluble transferrin receptor (sTfR) present in plasma is a truncated monomer of the transmembrane receptor. Recent studies have indicated that infections or inflammatory disease per se do not cause any significant change in circulating levels of sTfR. Therefore, unlike ferritin, the clinical interpretation of sTfR measurements is not influenced by ongoing acute phase responses.
Clinical situations in which sTfR measurement has been suggested as being especially useful include:-
- distinguishing iron-deficiency anaemia from the anaemia of infection, inflammatory disease or malignancy (anaemia of chronic disease, alcoholic liver disease)
- recognition of frank iron deficiency especially in pregnancy.
Soluble transferrin receptor is elevated in association with hyperplastic erythropoiesis, for example, in patients with haemolytic anaemia or beta-thalassaemia. Recent studies have also suggested that sTfR measurements are helpful when predicting the response to erythropoietin in patients with anaemia resultant from chronic renal failure.
The assay is a sandwich enzyme immunoassay by R&D Systems.
EQA: Instand
Reference Range
The normal range for serum soluble transferring receptor is 8.7 – 28.1 nmol/L for non-blacks residing <300 metres above sea level.
Sample Requirements
Collect blood in a tube containing no additives and allow to clot before centrifuging. A minimum volume of 200µl of serum is required for analysis.
Storage and Transport
Serum may be stored refrigerated at 4°C. External samples can be transported by 1st class post.
Turnaround Time
4 – 6 weeks
Price
Price available on application - please contact adrianturner1@nhs.net. Discounts could be available for significant workloads.
Contacts
Dr Kishor Raja
T: 020 3299 4127
Ms R Langworthy
T: 020 3299 4130
