Anemia Defined & Fe Deficiency

Question 1

Define Anemia

Answer 1

Inadequate red cell mass to adequately deliver O2 to peripheral tissues

Question 2

How is anemia measured?

Answer 2

Hgb, Hct, RBC count... but age & gender impact those numbers, such as Hgb:
Birth           17
1-3mo        14
3mo - 10y  12
11 - 15y     13
Adult man  15
Menstr F     13.5
Preg F        12
Hct follows a similar trend

Question 3

Define retic count, abs retic count, and retic index

Answer 3

Retic count: % of 1,000 RBCs
Abs Retic count: % * total RBC count (50k/uL)
RI = count * (pt hgb / norm hgb) * (1/stress)
Basically, RI is corrected for anemia to see if body is responding correctly

Question 4

Review Fe deficient anemia!

Answer 4

DO IT!!

Question 5

Factors that increase or decrease Fe absorption include:

Answer 5

Increase iron absorption:
Low pH: keeps iron soluble, more readily absorbable.
Iron is better transported in the presence of protein and amino acids.
Vitamin C keeps iron in ferrous state, thus more easily absorbed.
Higher quantity of iron ingested.
If erythropoiesis rates are up, iron is more actively picked up from the duodenum.
Decrease iron absorption:
Certain chelators (phytates, oxalates).
In many illnesses and during inflammatory progression, iron release from stores is halted, limiting hematopoiesis by reducing iron incorporation into heme.
The mechanism for this cessation is hepcidin, a small peptide produced in the liver that causes iron to be sequestered in intracellular storage forms. Hepcidin is actively produced during inflammation, infection, and abnormally high iron intake.

Question 6

Fe Def: findings on a CBC, PBS, and labs

Answer 6

CBC: microcytosis (low MCV), high RDW
Smear: hypochromia, wide range in the sizes
Labs: Look for low serum iron, low ferritin and ferritin saturation, high transferrin saturation.

Question 7

Fe overload damages

Answer 7

Heart (arrhythmia and CHF),
Liver (dysfunction and failure)
Endocrine organs (e.g., pancreatic endocrine function, diabetes).

Question 8

Fe overload treatment

Answer 8

If hemochromatosis (inc absorption), therapeutic phlebotomy (init and maintenance)
If hemosiderosis, (usually from transfusions):  iron chelators, such as Desferal given via IV or SC.  Newer preparations (e.g., Exjade) can be taken orally.