<prompt> Which of the following are features of iron deficiency anemia exceptIncreased RDWDecreased serum ironDecreased TIBCDecreased serum ferritin  <response>: Ref Harrison 19 th ed pg 627 The serum iron level repre- sents the amount of circulating iron bound to transferrin. The TIBC is an indirect measure of the circulating transferrin. The normal range for the serum iron is 50-150 mgdL; the normal range for TIBC is 300-360 mgdL. Transferrin saturation, which is normally 25-50, is obtained by the following formula: serum iron x 100 TIBC. Iron- deficiency states are associated with saturation levels below 20. There is a diurnal variation in the serum iron. 