USEFULNESS OF SERUM TRANSFERRIN RECEPTOR (sTfR) IN ANEMIC PATIENTS WITH RHEUMATOID ARTHRITIS (RA): COMPARISON WITH THE BONE MARROW IRON.

초록

OBJECTIVE - To investigate the usefulness of serum transferrin receptor (sTfR) in anemic patients with rheumatoid arthritis (RA) comparing with bone marrow storage iron and a panel of laboratory tests estimating the body iron status. METHODS - Fifty five patients with RA who had anemia (6 males and 49 females) underwent anemia study including hemoglobin concentration, complete blood cell count (CBC), mean corpuscular volume (MCV), red cell distribution width (RDW), serum iron/total iron binding capacity (TIBC), serum ferritin, and serum transferrin receptor. Erythrocyte sedimentation rate (ESR) and CRP were also measured as markers of the disease activity. Bone marrow aspiration for iron stain were performed in eighteen patients among them. sTfR was compared with bone marrow iron stain, hematologic and serologic tests for anemia, and markers of the disease activity. RESULTS 1) sTfR showed significant correlation with hemoglobin concentration, CBC, serum iron/TIBC, MCV and RDW. 2) Serum ferritin showed no significant correlation with hemoglobin concentration, CBC, serum iron/TIBC, MCV and RDW. 3) sTfR showed no significant correlation with ESR and CRP, whereas serum ferritin showed significant correlation with ESR and CRP (p=0.002, p=0.01) 4) sTfR was higher in patients with negative bone marrow iron stain than in those with positive iron stain. (p=0.04) CONCLUSION - These observations indicate that sTfR level is not influenced by inflammatory status in contrast to the serum ferritin. It may be useful assay for the determination of body iron status comparable to bone marrow iron stain in RA combined with anemia. It is suggested that the measure of sTfR can substitute invasive bone marrow study for diagnosis of iron deficiency anemia in patients with RA. 43(9, suppl):S185, 2000