Iron Deficiency

Question 1

Dietary iron is reduced to the ferrous state by?

Answer 1

duodenal ferric reductase (Dcytb),

Question 2

Dietary iron is transported into the enterocytes by which receptor?

Answer 2

divalent metal transporter 1 (DMT1)

Question 3

Iron leaves the enterocyte or liver and enters the circulation via the action of which protein facilitated by hephaestin?

Answer 3

ferroportin

Question 4

This hormone is secreted into the circulation, where it down-regulates the ferroportin-mediated release of iron from enterocytes, macrophages, and hepatocytes

Answer 4

Hepcidin

Question 5

binds to iron in the bloodstream and transports it to cells

Answer 5

Transferrin (Tf)

Question 6

Tf can bind about 300 mcg Fe/dl. This is how many seats are on the “iron bus”. Clinically, this value is known as?

Answer 6

total iron binding capacity (TIBC)

Question 7

How is the total iron binding capacity (TIBC) affected when the body is iron deficient?

Answer 7

This goes up when the body is iron deficient.

Question 8

The majority of iron is stored in what protein of the liver ?

Answer 8

Ferritin

Question 9

True or False: Non heme iron are 10 times less absorbable than heme iron

Answer 9

True

Question 10

This is the fraction of available Fe-binding sites which have iron bound to them. This is how many iron people are sitting on our iron bus. Clinically, this value is known as?

Answer 10

Transferrin saturation

Question 11

How is the transferrin saturation affected when the body is iron deficient

Answer 11

This falls as the body becomes iron deficient.

Question 12

How is iron excreted from the body?

Answer 12

There is no regulated excretion of iron. Iron leaves the body only when cells are lost.

Question 13

What is the major cause of iron deficiency in adults?

Answer 13

Blood Loss (menstruation, pregnancy, blood donation, GI blood loss, GU blood loss)

Question 14

In early iron deficiency, what will be depleted first?

Answer 14

Ferritin –> Iron stores (“savings account”)

Question 15

True or False: Iron deficiency always means anemic?

Answer 15

False

Only as iron deficiency becomes more profound will anemia occur

Question 16

After ferritin iron stores are depleted, what will be sacrificed?

Answer 16

The hemoglobin (checking account) falls

Question 17

Pica (consumption of dirt, paper, starch), thrombocytosis (increased platelets), koilonychia (concave nails), and pagophagia (craving ice) are clinical presentations of

Answer 17

iron deficiency

Question 18

Lab findings including: elevated RDW, low MCV, low ferritin, low serum iron, increased TIBC, and low transferring saturation indicate

Answer 18

iron deficiency

Question 19

In an otherwise healthy outpatient, this is the single best test for iron deficiency.

Answer 19

Ferritin test

Question 20

What does an iron panel include?

Answer 20

Fe, Tf, TIBC, %Tf sat

Question 21

What does an iron panel not include?

Answer 21

FERRITIN LEVEL

Question 22

Cytokines increase what iron regulator to decrease iron absorption from gut, decrease iron export out of liver, decrease transferrin and TIBC?

Answer 22

Hepcidin

Question 23

What are the main differences between Iron Deficiency and Anemia of Chronic Disease?

Answer 23

Iron Deficiency:

• Elevated TIBC
• Decreased Ferritin

AOCD:

• Decreased TIBC
• Normal or Elevated Ferritin