Fe affects organs differently, it is more toxic to some than others. Which is the most sensitive organ to Fe?
Which chromosome is the HFE gene found upon?
HFE is involved in ____1____ homeostasis.
HFE protein normally limits amount of iron uptake by gut and regulates amount of iron ____2____ in the tissues
Name the two common mutations in HFE.
Which one is by far the most common?
C282Y allele (most common)
What is the result of an HFE gene mutation?
HFE gene mutations produce altered HFE protein unable to properly regulate iron metabolism which results in excess iron storage in tissues.
What does HFE stand for?
What factors exacerbate haemochromatosis? (3)
Who is more at risk of developing haemochromatosis, men or women?
What is the exception?
Post-menopausal women are as at risk as men.
Why is haemochromatosis generally not evident until 40-60 years of age?
At birth everyone has normal Fe levels and it takes many years to accumulate toxic levels of Fe, hence the typical late life presentation.
Fe can accumulate in the heart causing damage and mainly leading to restrictive and dilated ____1____. Just like in the liver, the Fe is causing a fibrotic response. In restrictive ____1____ this leads to the stiffening of the ventricle walls (but not thickened walls) which causes a ____2____ in the pumping efficiency, especially during exercise.
Some patients go on to develop dilated ____1____ where the walls of the ventricle do become thickened (dilated).
Name the most widely used dignostic test for haemochromatosis.
Name the most effective dignostic test for haemochromatosis.
Measure level of serum ferritin.
Measure transferrin saturation.
Haemochromatosis patients should avoid what foods or dietary factors? (3)
Vitamin C (increases the absorption of iron) and iron supplements
Excessive consumption of alcohol
In managing haemochromatosis, doctors are looking to prevent the disease before plasma Fe overload, and well before ______ Fe overload.
Describe the mechanism of action of Hepcidin.
Hepcidin binds to ferroportin, thereby leading to ferroportin degradation and blockage of iron import.
Which unusual joints are affected by haemochromatosis-induced arthritis?
Knuckles and ankles can become quite swollen and painful.
Probably due to Fe disposition into the joint space or when the crystals that normally form cannot be cleared.