Serum transferrin receptor: a quantitative measure of tissue iron deficiency

Abstract

This study was undertaken to evaluate the role of serum transferrin receptor measurements in the assessment of iron status. Repeated phlebotomies were performed in 14 normal volunteer subjects to obtain varying degrees of iron deficiency. Serial measurements of serum iron, total iron-binding capacity, mean cell volume (MCV), free erythrocyte protoporphyrin (FEP), red cell mean index, serum ferritin, and serum transferrin receptor were performed throughout the phlebotomy program. There was no change in receptor levels during the phase of storage iron depletion. When the serum ferritin level reached subnormal values there was an increase in serum receptor levels, which continued throughout the phlebotomy program. Functional iron deficiency was defined as a reduction in body iron beyond the point of depleted iron stores. The serum receptor level was a more sensitive and reliable guide to the degree of functional iron deficiency than either the FEP or MCV. Our studies indicate that the serum receptor measurement is of particular value in identifying mild iron deficiency of recent onset. The iron status of a population can be fully assessed by using serum ferritin as a measure of iron stores, serum receptor as a measure of mild tissue iron deficiency, and hemoglobin concentration as a measure of advanced iron deficiency.

Variations in serum erythropoietin and transferrin receptor during phlebotomy therapy of hereditary hemochromatosis: A case report

“…This corresponds to the point at which both TS and S-Ft were at their lowest and the time when phlebotomy was stopped. An increase in S-TfR is a strong indication of a functional iron deficit and an increased rate of erythropoiesis (1,4). Thus, Patient no.…”

“…The measurement of serum transferrin receptor (S-TfR) has recently been reported to be of significance in the assessment of a number of hematological disorders, showing increased levels in iron-deficiency anemia and ineffective erythropoiesis, and decreased levels in aplastic anemia (1)(2)(3)(4)(5)(6)(7). These changes apparently reflect changes in TfR number on individual normoblasts as well as changes in erythroid mass (1,5,7).…”

“…These changes apparently reflect changes in TfR number on individual normoblasts as well as changes in erythroid mass (1,5,7). Measurement of S-TfR has also been found to be of particular value in identifying mild iron deficiency of recent onset (4). The serum level of the glycoprotein hormone erythropoietin (S-EPO) increases in response to anemia and decreasing hematocrit (8).…”

Erythropoietic activity and iron metabolism in autologous blood donors during recombinant human erythropoietin therapy

“…We observed a strong correlation between total erythropoietic activity expressed as increase of sTf R concentration and effective erythropoietic activity measured by reticulocyte count during the first 2 weeks of treatment. Serum TfR has also been reported to be an early parameter of tissue iron deficiency [28] and may, therefore, show some elevation not related to erythropoiesis in iron-deficient donors [29]. Indeed, the increase of sTf R during the last week of treatment when reticulocyte counts were declining was correlated with iron deficiency measured by the increase of FEP concentration.…”

Soluble transferrin receptor and zinc protoporphyrin – competitors or efficient partners?

“…In ID patients, the sTfR does not increase before IDE has developed. In individuals with simple storage iron depletion, sTfR levels are normal (6). sTfR is regarded as the most sensitive parameter of iron support to the erythropoiesis (8,10,19,22,26).…”