Utility of sTFR/Ferritin index to differentiate iron deficiency anaemia and anaemia of chronic disease

Abstract

Iron deficiency is a common condition that is usually diagnosed using conventional laboratory tests of iron status, such as serum ferritin and transferrin saturation. However, both ferritin and transferrin proteins are markedly influenced by inflammation, behaving as acute-phase reactants and making it difficult to differentiate between iron-deficiency anemia (IDA) and anemia of chronic disease (ACD). To assess the utility of sTfR/ Log ferritin Index to differentiate Iron deficiency anaemia and Anaemia of chronic disease. A cross-sectional study was conducted in the Department of Medicine, Victoria hospital and Bowring and Lady Curzon hospital, Bangalore Medical College and Research institute, Bangalore. A total of 150 blood samples were evaluated, i.e., 50 samples from iron deficiency anaemia group and 50 samples from patients with anaemia of chronic disorders & 50 samples from healthy normal individual. In present study, samples are age matched with mean age of control 45.66±10.23, ACD 50.68±18.03, IDA 48.14±18.47. Hb, MCV, MCHC & MCH were decreased in both the groups. However, the decrease in Hb & MCV was much more in IDA as compared to ACD. Microcytosis was seen in 92% cases of IDA while it was observed in only 11% cases of ACD. sTfR/ log ferritin index was >1.5 in 80% of IDA. 90% of ACD and control subjects had sTfR/log ferritin index <1.5. sTfR levels were significantly higher in IDA (7.7± 5.8) as compared to the ACD cases (1.6 ±0.89) (p<0.001). sTfR/Log ferritin index is significantly higher in patients with Iron deficiency anemia (9.34±10.25) as compared to ACD (0.76±0.52) (p<0.001). sTFR/Log ferritin index indices is very useful in differentiating pure IDA, ACD and ACD with coexisting iron deficiency, thus providing a non-invasive alternative to bone marrow iron.