The clinical significence of common iron parameters in iron deficiency anemia

Objective:To evaluate the clinical significance of iron parameters composed of Serum iron (SI) , Total iron-binding capacity (TIBC) , Transferrin saturation (TS), Serum ferrin (SF), Soluble transferrin receptor (sTFR) , Mean corpuscular volume (MCV) and Erythrocyte hemoglobin distribution width (RDW) in dignosis of Iron deficiency anemia(IDA). To identify the optimal cutoff point of SF measured with ELISA. Method:Two hundred and fifty-two patients with anemia from out-patient clinic or inpatient department entered the study. Based on the iron staining result of bone marrow smear as the gold standard for iron deficiency, patients were classified into two groups; IDA group and Non-ID A group. Iron parameters are SI, TIBC, TS, SF, sTFR, blood routine, bone marrow iron staining, ROC curve were used to evaluate iron parameters and to identify their optimal critical point. Result:The values of area under the curve (AUC) of each iron parameter are as followings: SI 0. 54(95%CI:0. 36 -0.71), TIBC0. 89(95 %CI: 0.75- 1.03), TS 0. 68(95%CI: 0. 58-0. 78), SF 0. 87(95%CI:0. 77 -0. 97), sTFR0. 92(95%CI:0. 84-1.00), MCV 0. 82(95%CI:0. 70-0. 94), RDW 0. 81(95%CI:0. 68-0. 94). sTFR has the highest value of AUC, and the order from high to low is AUCsTFR, AUCTIBC, AUCSF, AUCMCV, AUCRDW, AUCTS, AUCSI. The optimal critical point of SF assayed with ELISA is 50 ug/L. At that point, the sensitivity is 0. 85 and the specificity is 0. 96. Conclusion:①Among the parameters of SI, TIBC, TS, SF, sTFR, MCV and RDW, sTFR is the best for diagnosis of iron deficiency. The order of diadynamic value of these parameters is sTFRTIBCSFMCVRDWTSSI.②The optimal critical point of SF assayed with ELISA is 50 ug/L.