Iron deficiency is best demonstrated by:

Ans b (Se Ferritin)Ref: Davidson, 21 edpg. 1018Ferritin (n = 50 - 200 microg//)A measure of iron stores in the tissue and is the single best test to confirm iron deficiency Less than normal value of Se. ferritin is seen in:1. Iron deficiency2. Hypothyroidism3. Vitamin c deficiency Raised Se.ferritin value is seen in:1. Liver disease2. As an acute phase responseS. Iron (n= 50-150 microg/d/)Low in Iron deficiency anaemia (<30); also in anaemia of chronic disease, during acute phase response.Se. iron is raised in liver disease and also in haemolysisTIBC (n= 300-360 microg/dl)High in iron deficiency anaemia Low in anaemia of chronic diseaseLow iron-+ Low TIBC = ACDLow iron+ High TIBC = IDATransferrin saturation (n = 30-50%)<16% is consistent with IDA but less specific than ferritin.Transferrin saturation is less in ACD & IDA; normal orincreased in thalassaemia & sideroblastic anaemiaTransferrin levels are low in malnutrition. Nephrotic syndrome,liver disease as well as during acute phaseresponse.Transferrin levels are high in pregnancy & OCP use.Red cell distribution width (RDW) (n = 11.5 - 14.5)Coefficient of variation of RBC volume. Normal RDW - anaemia of chronic disease, aplastic anaemiaIncreased RDW - iron deficiency, B12 defeciency, folic acid deficiency