What is haemochromatosis?
Haemochromatosis is a genetic disorder of iron metabolism, whereby a person absorbs too much iron.
Iron accumulation takes time to occur and consequently severely high iron levels & the potential to cause organ damage may take several years. Hence early diagnosis and treatment can prevent these complications.
There are different genetic sub-types of haemochromatosis & it is important to point out that not all people diagnosed genetically with the condition will indeed accumulate iron to very high levels. Those individuals with no organ damage can expect have a normal life span. Those who already have significantly damaged organs can have more serious problems and may need ongoing monitoring and treatment.
In some cases haemochromatosis may damage the liver (cirrhosis, cancer), heart, or lead to arthritis, diabetes and sexual dysfunction.
Haemochromatosis is often a silent condition, which in many cases displays no symptoms.
As a person ages, and iron may accumulate some signs and symptoms may become evident. Such as tiredness, fatigue/lethargy, abdominal discomfort, joint pain, low libido (loss of sex drive), occasionally a person may develop a bronzed complexion in very high iron levels. These symptoms may not be present at all, or indeed may thought to be attributable to other causes hence the condition may go unrecognised for some time.
For many people a routine check-up with their GP or indeed often health insurance examinations often reveal the first indication of haemochromatosis through routine blood tests.
For the above reasons, many people with haemochromatosis remain undiagnosed.
Some undiagnosed iron overload sufferers, whose main symptom is fatigue, take iron tablets for years without medical advice these supplements are a serious danger to people with haemochromatosis.
Haemochromatosis is a genetic inherited condition. This means it was passed down to you through the DNA of your family tree. It is most common in people of Northern European descent.
It is a recessive condition which means that your parents may not have necessarily had the condition, however they may have been carriers, and have subsequently passed this onto you. This is explained in further detail later on this page, including the chances of your siblings and/or children having this condition.
The abnormal gene is extremely common, 1 in 7 normal people of European descent are carriers and 1 in 200 people in New Zealand have haemochromatosis.
Gene inheritance is said to occur when a particular family characteristic is passed on from one generation to another such as blonde hair or blue eyes. The gene for Haemochromatosis is recessive, this means that, people with Haemochromatosis must have inherited two separate genes, one from their mother and one from their father to have the condition. If a person only inherits one haemochromatosis gene they are said to be a carrier, and do not have the condition itself, but possess the ability to pass it onto their offspring. The diagram below shows the possible outcomes for offspring from two parents which are carriers:
How is it diagnosed?
Blood tests that are done to check for haemochromatosis include an iron saturation test and a serum ferritin. Most people who are affected (but not all) have an increased iron saturation of 55%, and/or a raised serum ferritin. Serum ferritin can also be falsely elevated in situations of illness including infection, inflammation, cancer or liver disease.
Genetic testing or genotyping of haemochromatosis can be performed by a simple blood test, once the disorder is suspected. This will reveal if a person is carrier of the condition or indeed has haemochromatosis & furthermore which genetic sub-type they have.
A blood test to analyse liver function is also often undertaken to assess for any indication/s of liver damage/abnormalities.
Haemochromatosis is treated by therapeutic venesection. This is a fancy name for the removal a blood a process very similar to that of blood donation. The person lies down on a bed or in a lazyboy chair, and a needle is placed into a person’s vein in their arm and a small amount of blood (usually 500mls) is drained into a collection bag over 10-15 minutes. Blood pressure is monitored & the person is encouraged to rest for 10 minutes following the procedure & to have a drink of juice.
Therapeutic venesection in New Zealand is carried out in a variety of settings including: hospital outpatient clinics, regional blood testing laboratories, the New Zealand Blood Service & occasionally in some GP practices.
Frequency of venesection required for a person varies greatly. Typically when a person is newly diagnosed they require more regular venesection this could be anywhere from weekly, fortnightly to monthly, depending on the level of iron that they presented with. This intensive phase is to deplete the bodies’ iron stores to an acceptable level. Target parameters again can vary depending on several factors & will be determined by the treating doctor. A serum ferritin of 50-100 ug/L is a reasonable target however is subject to individual patient factors. A transferrin saturation of 50% is preferable.
Once a person has their iron stores depleted this can take up to 12 months. They may enter a maintenance phase of venesection. Whereby decreased frequency of venesection is required to maintain the iron levels at an acceptable point. Again, this varies between individuals but may be 3-6 monthly.
Furthermore some individuals who have their iron stores depleted may never again accumulate iron to such a high level as to require venesection treatment. Their bodies may not re-accumulate iron and/or simply their age precludes this being a problem in future years. In such circumstances a person may enter a monitoring phase whereby they are simply monitored by their GP through an annual blood test to check their iron levels.
Quick tips for therapeutic venesection
- Ensure you drink plenty of fluids prior to having a venesection. Particularly in the warmer summer months. This aids in recovery by preventing hypotension (low blood pressure) & enhances nice full veins for easy needle access = less ouch!!
- Listen to your body – take the time to rest 10 minutes after the procedure. Have a juice & a snack. If you feel tired, then rest.
- Avoid heavy lifting from the affected arm for 24 hours following venesection. The arm may be tender & you don’t want it to start bleeding again if you knock it. Leave the dressing on overnight for this reason also.
- If you are anxious tell the nurse your concerns, they will do their best to reassure & explain things to you & may even be able to schedule your appointment at a time of the day where a support person can accompany you.
Dietary management recommendations for people living with haemochromatosis
* People who already have liver abnormalities should abstain from alcohol.
** Some minerals (zinc, cobalt, manganese & chromium) share absoption pathways with iron & may also be retained in the liver.
*** People with haemochromatosis are at risk of developing infection from the organism ‘Vibrio vulnificus’ which grows as marine flora. The risk of severe infection/sepsis is very rare and cooked shellfish is fine.