ABSTRACT
Anemia is the most common extraarticular manifestations of rheumatoid arthritis [RA] in which, differentiating iron deficiency anemia from anemia of chronic disease may be difficult because of similarities in presentation. The study was performed to elucidate the use of serum transferrin receptor [sT f R] and s T f R / log ferritin as non-invasive laboratory indices to distinguish between iron deficiency anemia [IDA] and anemia of chronic disease [ACD]. Also, to establish a method to identify functional iron deficiency in RA patients with anemia. The study compromised 30 RA patients with anemia diagnosed according to American Collage of Rheumatology Revised Criteria for diagnosis of RA. The patients were divided into two groups after bone marrow aspiration and staining for iron [Group [I], including 17 patients with normal iron store [ACD]; Group [II], including 13 patients with depletion iron store [IDA]]. All patients were subjected to the following investigations: [CBCs and RBCs indices, ESR, CRP, rheumatoid factor and iron status study]. RBCs study showed a significant difference between two groups as regards; HB, [p<0.05]; PCV, [p<0.05] and RDW, [p<0.01], but no significant differences between two groups were found as regards; MCH, MCHC, serum iron and serum ferritin. Our results demonstrated a significant differences between two groups as regard to total iron binding capacity [TIBC], [p<0.01]; sT f R, [p<0.01]; sTfR / ferritin index, [p<0.01] and highly significant in sTfR / log ferritin index, [p<0.001]. s T f R could be introduced as a new tool for diagnosis of iron depletion, also sTfR/log ferritin index along with TIBC alone or TIBC and RDW have much more value in differentiation between IDA and ACD in RA patients