Single values of serum transferrin receptor and transferrin receptor ferritin index can be used to detect true and functional iron deficiency in rheumatoid arthritis patients with anemia

Objective, To elucidate the use of serum transferrin receptor (sTfR) to dis tinguish between iron-deficiency anemia (IDA) and anemia of chronic disease (ACD), and to establish an improved scheme to identify functional iron def iciency (FID) in rheumatoid arthritis (RA) patients with anemia. Methods, We studied 30 anemic RA patients whose iron status was confirmed b y bone marrow examination and determination of the sTfR level, serum ferrit in level, and sTfR-log ferritin index (TfR-F Index). All patients with dimi nished or exhausted iron stores (n = 18) received oral iron supplementation . Results, Baseline values of sTfR and the TfR-F Index predicted the response correctly in all patients who received supplementation treatment and were normal in 10 of 11 patients with normal initial iron stores (ACD). Conclusion, The results of this study elucidate the roles of sTfR and the T fR-F Index in the differential diagnosis between IDA and ACD and provide di rect evidence that these parameters are useful in detecting FID, irrespecti ve of the concurrent iron storage status.