Genetic haemochromatosis is an inherited condition where iron accumulates in the body – it affects Caucasions. If undiagnosed and untreated this may result in damage to important organs, particularly the pancreas (resulting in ‘bronze diabetes’), liver (cirrhosis), heart (cardiomyopathy) and arthritis.
The genetic mutation which resulted in haemochromatosis first developed in the Vikings and Celts some 2000 years ago.
SYMPTOMS most often develop after age 40 and may include :
GENETICS
There are many forms of haemochromatosis which is the most common genetic condition in our community around 1 in every 200 Caucasians.
The condition is ‘autosomal recessive’, meaning that a defective gene has to be acquired from each parent. Thus both parents must be either a carrier or have haemochromatosis for the offspring to be affected. People who have a single defective gene are carriers.
Haemochromatosis genes can be checked by a simple blood test.
There are 2 common types:
Not all people with C282Y haemochromatosis will require active treatment – probably around 50%.
Men are more likely to develop complications than women.
TREATMENT requirements are determined by the amount of iron in the blood and stored in the body – this is measured via a simple blood test which measures iron and ferritin levels. Ferritin is a protein which stores iron and is the main measure of iron overload. Normal ferritin levels should be less than 200 ug/l in females and less than 300 ug/l in males.
Haemochromatosis requiring treatment cannot be treated by diet alone – it is treated by regular venesection (drainage of 1 pack of blood) – this may be a lifelong requirement and is usually done every 2 to 4 months. Blood is drained to initially reach a ferritin of less than 50 ug/l and then to follow a maintenance program which keeps the ferritin under 100ug/l. With advancing age, frequency of venesection tends to reduce.
As well as venesection, iron supplements must be avoided. “Iron tablets” obviously should not be taken, but foods with iron supplements include : many ‘fortified’ breakfast cereals, multivitamins, some types of milk, orange juices, ‘energy food drinks’ and many sports energy bars or drinks.
People having venesections may benefit from extra folate (green leafy vegetables) and vitamin B12 (red meat, seafood, skim milk, swiss cheese, eggs) in their diet. This may reduce the risk of anaemia.
Alcohol intake needs to be limited to safe levels as this will increase the risk of liver damage.
For unknown reasons, people with a high ferritin level are prone to blood poisoning from a bacteria called vibrio vulnificus – which can be found in raw seafood especially oysters and clams, most often sourced from India, Asia and Mexico (although occasionally in Australian seafood) – hence people with haemachromatosis should have only cooked seafood (cooking kills the bacteria).
People with haemochromatosis not severe enough to require venesection should avoid dietary iron supplements.
Where a person is diagnosed with haemachromatosis, the genetics should be explained and relevant family members advised to undertake testing to see whether they too have the condition or carry the defective gene.
Should complications be present (liver, diabetes, heart etc) specialist assessment will probably be required.
An annual check to ensure no complications have developed should be undertaken – especially checking liver function, sugar levels and the heart. The haemoglobin level also needs monitoring as frequent venesection may result in anaemia – if this occurs venesection frequency should be reduced.
The genetic mutation which resulted in haemochromatosis first developed in the Vikings and Celts some 2000 years ago.
SYMPTOMS most often develop after age 40 and may include :
- lethargy
- abdominal discomfort
- symptoms of diabetes
- symptoms of liver disease
- changes in body hair distribution
- a bronze skin discolouration
- symptoms of heart disease such as shortness of breath on exercise
- irritability, depression, mood swings or declining memory
- arthritic joints
GENETICS
There are many forms of haemochromatosis which is the most common genetic condition in our community around 1 in every 200 Caucasians.
The condition is ‘autosomal recessive’, meaning that a defective gene has to be acquired from each parent. Thus both parents must be either a carrier or have haemochromatosis for the offspring to be affected. People who have a single defective gene are carriers.
Haemochromatosis genes can be checked by a simple blood test.
There are 2 common types:
- C282Y is the most common and most severe form of the disease.
- H36D is a less serious type and is usually not associated with a significant iron build up and usually requires no treatment. People who are carriers of both C282Y and H36D can have an iron build up but this too is usually not severe enough to warrant treatment.
Not all people with C282Y haemochromatosis will require active treatment – probably around 50%.
Men are more likely to develop complications than women.
TREATMENT requirements are determined by the amount of iron in the blood and stored in the body – this is measured via a simple blood test which measures iron and ferritin levels. Ferritin is a protein which stores iron and is the main measure of iron overload. Normal ferritin levels should be less than 200 ug/l in females and less than 300 ug/l in males.
Haemochromatosis requiring treatment cannot be treated by diet alone – it is treated by regular venesection (drainage of 1 pack of blood) – this may be a lifelong requirement and is usually done every 2 to 4 months. Blood is drained to initially reach a ferritin of less than 50 ug/l and then to follow a maintenance program which keeps the ferritin under 100ug/l. With advancing age, frequency of venesection tends to reduce.
As well as venesection, iron supplements must be avoided. “Iron tablets” obviously should not be taken, but foods with iron supplements include : many ‘fortified’ breakfast cereals, multivitamins, some types of milk, orange juices, ‘energy food drinks’ and many sports energy bars or drinks.
People having venesections may benefit from extra folate (green leafy vegetables) and vitamin B12 (red meat, seafood, skim milk, swiss cheese, eggs) in their diet. This may reduce the risk of anaemia.
Alcohol intake needs to be limited to safe levels as this will increase the risk of liver damage.
For unknown reasons, people with a high ferritin level are prone to blood poisoning from a bacteria called vibrio vulnificus – which can be found in raw seafood especially oysters and clams, most often sourced from India, Asia and Mexico (although occasionally in Australian seafood) – hence people with haemachromatosis should have only cooked seafood (cooking kills the bacteria).
People with haemochromatosis not severe enough to require venesection should avoid dietary iron supplements.
Where a person is diagnosed with haemachromatosis, the genetics should be explained and relevant family members advised to undertake testing to see whether they too have the condition or carry the defective gene.
Should complications be present (liver, diabetes, heart etc) specialist assessment will probably be required.
An annual check to ensure no complications have developed should be undertaken – especially checking liver function, sugar levels and the heart. The haemoglobin level also needs monitoring as frequent venesection may result in anaemia – if this occurs venesection frequency should be reduced.
