B12 and folate deficiency

Question 1

In what form is Iron toxic ?

Answer 1

Free form

Question 2

Ferric Iron is in what kind of form?

Answer 2

Oxidized Fe3+

Question 3

Ferrous Iron is in what kind of Form?

Answer 3

Reduced Fe2+

Question 4

What is the role of Transferrin?

Answer 4

Carry the Ferric form of Iron in the blood

Question 5

What is the role of Ferritin?

Answer 5

Stores the Ferrous form of iron

Question 6

What is the role of Hemosiderin?

Answer 6

storage of iron in a disorganized manner

Question 7

Looking at lab values the Mean Corpuscular Volume refers to what?

Answer 7

The size of the erythrocyte (Microcytic vs Macrocytic)

Question 8

When looking at lab values the Hemocrit number tells you what?

Answer 8

determines the number of RBCs in the body

Question 9

What does it mean when hemoglobin is low?

Answer 9

There will be a decrease in iron carrying capacity

Question 10

Why is iron binding low with transferrin compared to the others?

Answer 10

Because when its bound to transferrin its exposed to oxygen which can cause oxidative damage

Question 11

What two things faciliate iron uptake?

Answer 11

Vitamin C and Ascorbic Acid

Question 12

What 4 things inhibit iron uptake?

Answer 12

1) phytates
2) antacids
3) phosphates
4) tannins

Question 13

What transports iron from the lumen into the enterocyte?

Answer 13

DMT1

Question 14

What transports iron from the enterocyte into the circulation?

Answer 14

Ferriportin

Question 15

When there is a decrease in transferrin saturation what does that mean?

Answer 15

It means there is not enough iron in the blood so transferrin is not taking it up as readily so it just circulates and circulates

Question 16

If you have an elevated sTFR what does it mean?

Answer 16

means there is an increase in receptors to try and bind to iron. So basically not enough iron is present

Question 17

during an infection or cancer pathogens need iron for there growth so what blocks ferriportin from releasing iron into the system?

Answer 17

Hepcidin

Question 18

A patient with Inherited hemochromatosis what kind of gene polymorphism does he/she have?

Answer 18

HFE polymorphism

Question 19

what does HFE polymorphism do?

Answer 19

It upregulates DMT1 during iron transport, so you will have an increase of iron into the cells of the Liver and Cardiac tissue.

Question 20

An accumulation of Hemosiderin due to the HFE polymorphism is bad because of what?

Answer 20

Because it will disrupt ferritin storage and destroy its structure.

Question 21

What are 2 examples of acquired Iron Loading anemia?

Answer 21

Thalassemia and Sideroblastic anemia

Question 22

During Iron Loading anemia what will you see happen to the RBCS

Answer 22

RBCs will breakdown so there is a increase of iron in the circulation

Question 23

In Chronic Liver disease what happens?

Answer 23

No longer able to store or regulate iron

Question 24

What is the role of both Folate and B12 metabolism?

Answer 24

DNA synthesis

Question 25

Which Deficiency has neurological symptoms like ataxia?

Answer 25

B12 deficiency

Question 26

What 2 things are needed to take up B12 ?

Answer 26

Intrinsic Factor and colabamine receptor

Question 27

What is pernicious anemia? and why does it occur?

Answer 27

B12 Deficiciency because of the loss of Intrinsic factor

Question 28

A patient with a methylmalonyl CoA mutase deficiency will result int he accumulation of what substrate?

Answer 28

Methyl malonic acid

Question 29

Methionine synthase needs which Cofactor to function properly?

Answer 29

B12

Question 30

In the presence of Methionine synthase what does it convert homocystene to? and What is the role of that pathway?

Answer 30

Homocystiene is converted to methionine which is needed for the methylation of DNA/RNA and proteins

Question 31

What is the Ironbound form of protoporphin IX called?

Answer 31

Heme

Question 32

What is ferrochelatases job in the bone marrow?

Answer 32

It looks for Iron in the bone marrow. Once it finds iron it puts it on protoporphin IX

Question 33

What happens to protoporphin IX after it is formed?

Answer 33

Gets put on a globin protein to make hemoglobin

Question 34

Lead Poisoning will inhibit what two things?

Answer 34

ALA dehydratase and ferrochalatase

Question 35

Why is iron able to enter the cell when its in the presence of ascorbic acid?

Answer 35

Ascorbic acid maintains iron in an available state (reduced state) for transfer by the DMT 1 transport protein

Question 36

What are two Amino acids that can chelate Iron in order to bind to the transferrin ?

Answer 36

Glutamate and Aspartate (remember you need acidic amino acids to chelate the iron)

Question 37

Which clinical presentation is expected to result in the greatest loss of bodily iron stores?

Answer 37

Menstruation

Question 38

What is the name of a blood test which provides similar information to Transferrin saturation %?

Answer 38

Total Iron Binding Capacity (TIBC) (Remember a high saturation % would be a low total iron biding capacity and vice versa)