Hereditary haemochromatosis (HH) is a multiorgan disease in which iron regulation is disrupted, resulting in the toxic accumulation of iron in vital organs leading to life threatening complications such as cirrhosis, diabetes, heart disease etc (1).
- the normal body content of iron is 2-6 g; patients nd with haemochromatosis may have 50-60 g.
It is thought to be inherited in an autosomal recessive manner in people of northern European ancestry (1)
- atypical forms (a fifth of cases) have been described outside the northern European stereotype (2)
Mutations in the HFE gene on chromosome 6 (HFE-HH) and non-HFE mutations (non HFE-HH) predisposes an individual to increased, inappropriate absorption of dietary iron resulting in iron overload and organ damage (1)
- HFE gene is responsible for the regulation of the primary iron regulatory hormone, hepcidin.
- excess iron in body causes hepatocytes to secrete hepcidin which in turn decreases intestinal iron absorption by enterocytes and decreases iron release by macrophages
- mutation of the HFE genes causes decreased hepcidin expression in response to elevated iron levels resulting in unregulated control of iron levels (1).