Haemochromatosis

Question 1

Haemochromatosis is a genetic mutation leading to the build up of iron in tissues. What is the incidence of haemochromatosis?

1 - 1.25 cases per 100,000
2 - 12.5 cases per 100,000
3 - 125 cases per 100,000
4 - 1250 cases per 100,000

Answer 1

1 - 1.25 cases per 100,000

Mildly more common in men because women can get rid of more blood during menstruation

Question 2

Haemochromatosis is a gentic mutation leading to the build up of iron in tissues. What age does the incidence of haemochromatosis peak?

1 - 20-30
2 - 30-40
3 - 40-50
4 - 50-60

Answer 2

4 - 50-60

Typically because it is a slow disease and takes time for iron to build up in the body

Question 3

Which of the following groups are most at risk of developing haemochromatosis?

1 - asians
2 - black African Americans
3 - native Indians
4 - caucasians

Answer 3

4 - caucasians

Question 4

Haemochromatosis is a genetic disorder. What is the inheritance type that this is passed on?

1 - autosomal dominant
2 - X-linked recessive
3 - X-linked dominant
4 - autosomal recessive

Answer 4

4 - autosomal recessive
Haemochromatosis (HFE) gene on chromosome 6 is most common

Autosomal = not a sex chromosome
Recessive = 2 mutated genes needed

Sex chromosome is an X or a Y

Question 5

Generic Haemochromatosis is termed primary. Is this condition always primary (i.e. genetic)?

Answer 5

• No

Blood transfusions can cause this, RBCs will die after 120 days, but iron remains

Question 6

Which of the following is NOT a cause of secondary haemochromatosis?

1 - blood transfusions
2 - liver disease
3 - disease of erythropoiesis
4 - iron with vitamin C overload
5 - graves disease
6 - thalassemia

Answer 6

5 - graves disease

Erythropoiesis makes RBCs, no RBCs means lots of iron left in the body

Liver disease means low or no hepcidin, meaning poor control of iron absorption in the blood

Thalassemia causes faulty RBCs, so iron is not transported properly, meaning more left in the circulation

Question 7

Haemochromatosis is when there is too much iron in the body leading to toxicity. Why does the body have too much iron?

1 - body makes too much iron
2 - too much iron absorbed in the GIT
3 - no iron excreted from the body
4 - kidneys reabsorb iron in tubules

Answer 7

2 - too much iron absorbed in the GIT

Typically we absorb 1mg/day
Haemochromatosis 4mg/day

Question 8

Where is iron typically absorbed in the GIT?

1 - 1st and 2nd part of the duodenum
2 - duodenum and ileum
3 - duodenum and jejunum
4 - jejunum and ileum

Answer 8

3 - duodenum and jejunum

Question 9

The fenton reaction is what is used to convert iron in the form of Fe3+ which is what is transported around the body into Fe2+, which is what binds oxygen in RBCs. What does the Fenton reaction produce that can become toxic?

1 - hydrogen peroxide (H2O2)
2 - hydroxyl radicals (OH)
3 - hydrogen (H+)
4 - water (H2O)

Answer 9

2 - hydroxyl radicals (OH)

Excess OH can become toxic and damage cells and tissues

Question 10

Although haemochromatosis can present with broad symptoms such as fatigue, arthralgia and impotence, there is a classical triad. Which of the following is NOT part of this triad?

1 - pancreatitis
2 - cirrhosis
3 - diabetes
3 - bronze skin pigmentation

Answer 10

1 - pancreatitis

Question 11

Patients with haemochromatosis can present with arthralgia, referred to as non-inflammatory osteoarthritis. Typically all of the following joints are affected, EXCEPT which one?

1 - hips
2 - ankle
3 - shoulder
4 - metacarpophalangeal and proximal interphalangeal joints

Answer 11

2 - ankle

Question 12

What is the storage form of iron called?

1 - transferrin
2 - haemoglobin
3 - ferritin
4 - feroportin

Answer 12

3 - ferritin

This is essentially a measure of iron in the blood

Question 13

What is the transporter of iron called?

1 - transferrin
2 - haemoglobin
3 - ferritin
4 - feroportin

Answer 13

1 - transferrin

Question 14

The majority of iron is used to stimulate and then bind with RBCs. Otherwise which organ is the main point where iron is stored?

1 - skin
2 - kidneys
3 - pituitary gland
4 - heart
5 - liver
6 - gonads

Answer 14

5 - liver

Iron is stored in all other organs as well in the form of ferritin

Due to the fenton reaction, this iron can then cause tissue damage due to hydroxyl radicals (OH)

Question 15

What is released to modulate the levels of iron in the blood, and is increase in the circulation when iron stores are high?

1 - transferrin
2 - haemoglobin
3 - hepcidin
4 - feroportin

Answer 15

3 - hepcidin

Able to inhibit iron absorption from the GIT by inhibiting feroportin (transporter on enterocytes that allows iron into the blood)

Question 16

To diagnose haemochromatosis we can measure ferritin, the storage form or iron. What is the normal level of ferritin?

1 - 2-3ng/ml
2 - 20-230 ng/ml
3 - 300-2300 ng/ml
4 - 3000-23,000 ng/ml

Answer 16

2 - 20-230 ng/ml

Raised:
>674 picomols/L in men
>449 picomols/L in women

Question 17

To diagnose haemochromatosis we can measure transferrin saturation. What % of saturation of transferrin would suggest haemochromatosis?

1 - >15%
2 - >30%
3 - >45%
4 - >80%

Answer 17

3 - >45%

Normal levels are 215 - 380 mg/dl.

Question 18

To diagnose haemochromatosis we can measure things in the blood. Which 2 of the following would typically be raised in haemochromatosis?

1 - ALP
2 - GGT
3 - AST
4 - ALT

Answer 18

3 - AST
4 - ALT

Question 19

If we suspect a diagnosis of haemochromatosis, we could do a FBC. Would this be normal or abnormal?

Answer 19

• typically normal

But look for other causes of fatigue, anaemia, raised WBC as in infection etc..

Question 20

Which of the following would NOT typically be considered if we suspected a diagnosis of haemochromatosis?

1 - HFR gene testing
2 - liver biopsy (ferritin >2247pmol/L)
3 - renal function

Answer 20

3 - renal function

Liver biopsy helps identify level of fibrosis and disease

Question 21

Iron deposits where can increase the risk of diabetes in haemochromatosis?

1 - thyroid gland
2 - gonads
3 - heart
4 - pancrease

Answer 21

4 - pancrease

A blood glucose may help confirm pancreatic involvement

Question 22

What effect can haemochromatosis have on the heart?

1 - increased risk of arrhythmias
2 - increased risk of HF
3 - increased risk of STEMI
4 - increased risk of dilated or cardiomegaly

Answer 22

4 - increased risk of dilated or cardiomegaly

An ECG or echo can help diagnose this early

Question 23

What hormone can be measured to assess the impact of haemochromatosis in men?

1 - growth hormone
2 - testosterone
3 - oestrodial
4 - cortisol

Answer 23

2 - testosterone

Main hormone affected in men

Typically due to deposits in gonads and pituitary gland and can lead to Hypogonadotrophism

Question 24

Which vitamin helps with the absorption of iron?

1 - vitamin C
2 - vitamin D
3 - vitamin A
4 - vitamin K

Answer 24

1 - vitamin C

Avoid this in haemochromatosis

Question 25

Haemochromatosis can be staged 0-4, what stages require venesection?

1 - all stages
2 - stages 0-2
3 - stages >1
4 - stages 2-4

Answer 25

4 - stages 2-4

Stages 0-1 will be managed in primary care

Question 26

If venesection is not an option, an iron chelator can be used. Which of the following is the iron chelator that can be used in Haemochromatosis?

1 - Denosumab
2 - Hydroxycobalamin
3 - Deferasirox
4 - Spironolactone

Answer 26

3 - Deferasirox