Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MD2 Pathology > Iron Studies > Flashcards

Iron Studies Flashcards

1
Q

What is the charge on ferrous iron?

A

2+ (reduced)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the charge on ferric iron?

A

3+ (oxidised)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 4 main functions of iron?

A

Oxygen carriers
Oxygen storage
Energy production (cytochromes for ox phos, Krebs cycle enzymes)
Liver detoxification (cytochrome p450)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How much iron is ingested daily on average? How much is absorbed?

A

10-20 mg

1-2 mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How is iron absorbed?

A

Reduced to ferrous form in low pH of stomach and separates from ligand
Converted back to ferric form in high pH of intestine and is absorbed
Reduced as it is absorbed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is iron stored?

A 
In ferritin as the ferrous form
In haemosiderin (slow release form)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is iron transferred?

A

Transferrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the normal saturation of transferrin?

A

40%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the roles of HFE?

A

Controls the rate at which transferrin can be absorbed into the body
Also has effects on hepcidin and therefore the release of iron from cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the classical mutation in haemochromatosis?

A

C282Y mutation in HFE

Can also have C282Y and H63D heterozygote

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the role of the iron response element (IRE)

A

High iron
Iron binds to and represses action of IRE
IRE does not bind to the mRNA transcript for transferrin
mRNA is degraded
Less transferrin is produced
Opposite occurs with low iron, opposite is true for ferritin production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

List 7 morbidities associated with haemochromatosis

A 
Liver disease
DM
Cardiac dysfunction
Skin pigmentation
Arthropathy
Gonadal dysfunction
FHx (can be passed on)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When does iron start to accumulate in haemochromatosis?

A 
After child (turnover is reduced)
Same is true in normal population (ferritin is higher in males than pre-menopausal females due to menstruation in both diseased and normal populations)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the threshold for organ damage (esp liver) in iron excess?

A

20g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the findings on iron studies in iron excess?

A

High ferritin
High iron saturation
Low transferrin (due to binding of IRE)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is ferritin not a good test for haemochromatosis?

A

Level varies depending on type of mutation and whether pt is heterozygous or homozygous

17
Q

In what population is ferritin a good test for haemochromatosis?

A

In women

18
Q

Above what ferritin level does ALT start to rise?

A

1000

19
Q

What is the effect of oestrogen on transferrin?

A

Increases

20
Q

What is the cut-off for what is considered a “high transferrin” in a pregnant woman?

A

~6

21
Q

What is the difference between iron depletion and iron deficiency?

A

Iron depletion refers to low ferritin in a non-anaemic person
Iron deficiency is a clinical syndrome with symptoms and signs of microcytic anaemia

22
Q

List 7 signs of IDA

A 
Weakness
Fatigue
Headache
Irritability
Sore tongue
Angular chelitis
Nail changes
23
Q

How is iron lost and how much is lost this way?

A

Sweat, skin, gut: 1 mg/day
Menses: additional 1-2 mg/day
+ more if pregnant, breast-feeding or antenatally

24
Q

List 8 causes of iron deficiency

A 
Dietary deficiency
Malabsorption
Gut ulceration
Tumours
Infection
Menorrhagia
Other rarer causes
25
Q

What 3 malabsorption states are often associated with iron deficiency?

A

Coeliac disease
Achlorhydria (not associated with PPI)
Bowel resection

26
Q

When might gut ulceration occur?

A

Reflux
PUD
Crohn’s

27
Q

List 3 sites for tumours which can cause iron deficiency

A

Gut
Kidney
Uterus

28
Q

List 2 infections which can cause iron deficiency

A

Hookworm

Malaria

29
Q

List 4 other rarer causes of iron deficiency

A

Intravascular haemolysis
Pulmonary haemosiderosis
EPO therapy
Dialysis

30
Q

What are the findings on iron studies in IDA?

A 
Low ferritin
Low iron saturation
High transferrin
Anaemia (low Hb)
Low MCV
31
Q

What ferritin level causes low Hb?

A

<10

32
Q

What ferritin level causes low MCV?

A

<10 to see microcytosis)

33
Q

What ferritin level causes high RDW?

A

<40

34
Q

Why can iron be normal in certain inflammatory conditions (e.g. UC)?

A

mm

35
Q

What can siderophore infusion be used to treat?

A

Iron overload

36
Q

What is the effect of fever on siderophore production?

A

Decreases

37
Q

How does the immune system respond to the detection of bacteria to prevent their access to iron?

A

White cell releases lactoferrin, which binds iron in acid environment (environment of inflammation)
Cytokines induce APP production
Caeruloplasmin oxidises iron
Haemopexin removes heme from circulation
Haptoglobin removes Hb from blood
Hepcidin and ferroportin decrease iron release

38
Q

What is the effect of inflammation on iron studies results?

A 
Decreased transferrin
Decreased iron saturation
Decreased iron
Increased ferritin
Reduced Hb
Normal MCV

MD2 Pathology (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions