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What is True about iron deficiency anemia in children – a) Iron absorption from terminal ileumb) Cow milk contain less iron than breast milkc) Serum ferritin depletes firstd) Decreased alertnesse) Decreased Red cell distribution width (RDW) and explain in detail?
Iron is absorbed from proximal small intestine mainly from the duodenum.
Cow milk has a slightly more amount of iron than breast milk, However, the bioavailability of iron of breast milk is much greater than cow milk.

Clinical manifestations 

Pallor is a most important sign of iron deficiency. In fact WHO recommended the use of palmar pallor as a screening measure for anemia.
Pagophagia, the desire to ingest unusual substances such as ice or dirt may be present.
In some children, the ingestion of lead containing substances may lead to concomitant plumbism & helminthic parasitic infection.
In severe anemia, irritability and anorexia are prominent. Tachycardia and cardiac dilatation occur. A systolic murmur is often present.
Iron deficiency affects attention span, alertness and learning in both infant and adolescents.

Laboratory findings

S. ferritin depletes first
Next, serum iron level decreases, the iron binding capacity of serum (serum transferrin) increases, and percent saturation (transferrin saturation) is reduced.
RDW is increased in iron deficiency anemia.