About haemochromatosis

Dice

  1. What is haemochromatosis?
  2. Symptoms and signs
  3. Diagnosis
  4. Treatment
  5. Inheritance
  6. Living with haemochromatosis


What is haemochromatosis?

Haemochromatosis is the condition of iron overload in the body. The iron overload comes about because the body continually absorbs more iron from the diet than it needs. The body is then unable to rid itself of the excess. The excess slowly builds up over a number of years and damages the organs where it is stored. It is rare for iron to build up to a damaging level in childhood, and it often does not happen for several decades.

The underlying cause is the inheritance of a mutated gene. The faulty gene stops the normal body iron control working properly. A faulty gene, therefore haemochromatosis, can only be inherited. Haemochromatosis cannot be caught from somebody else, nor can you give it to someone else, except by having a child.

Although haemochromatosis is closely associated with one particular gene mutation, not everybody who has inherited that gene mutation will develop iron overload: indeed the proportion that does so may be quite small. Inheritance of the mutated gene greatly increases the likelihood of developed haemochromatosis but does not on its own cause haemochromatosis. Other factors must be involved, but it is not yet known what they are.

In the early stages of haemochromatosis there may be no evident signs or symptoms. It takes many years for significant iron overload to occur, and it takes even more for organ and tissue damage to become evident. If signs and symptoms are present, they can take any one of many forms. Even in fairly advanced cases the patient may not display clear, tell tale symptoms. This is why haemochromatosis is often under-diagnosed. Persistent lethargy and tiredness are the most common complaints.

Diagnosis at an early age leads to less or no organ damage. On the other hand, the older the individual at the time of diagnosis, the higher iron storage levels may be the greater the risk of organ damage. The most common age of diagnosis for members of the Haemochromatosis Society was 52, but the range is from 26 to 77. People are being diagnosed earlier today because of increased awareness of the condition.


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Symptoms and signs

Organ damage is one of the most serious complications of iron overload that can occur in the undiagnosed patient. The organs that may be affected are the liver, heart, pancreas and endocrine glands. Major complications that sometimes arise from haemochromatosis include:

Liver Disorders:
Fibrosis; cirrhosis; hepatocellular carcinoma (cancer) and portal hypertension.

Joint and bone problems:
Osteoarthritis; synovitis (the painful swelling of a joint); osteonecrosis; chondrocalcinosis; osteoporosis.

Heart problems:
Various types of cardiomyopathy (heart failure) and cardiomegaly conditions occur. These include cardiac arrythmias (irregularities of the heart beat) and ventricular dysfunction. These conditions usually occur in the younger person when iron levels are grossly elevated over a prolonged period of time. Echocardiography in early stages of the disorder can detect the presence of inter-ventricular septal thickness that reflects iron deposition.

Some improvement in these conditions usually occurs when iron stores are reduced.

Skin colouration and conditions:
Bronze pigmentation occurs because iron builds up within and around the sweat glands. This causes an increase in iron in the epidermis. If the sweat glands are affected it can cause heavy, dark staining with a particular colour. Old scars can be highly pigmented, and the conjunctiva and lid of the eye can be coloured. If the skin is heavily affected it can be a slate grey in colour. Fine skin is noted with diminished facial, pubic and axillary hair. There can be dryness associated with itchiness to varying degrees.

Diabetes mellitus:
Diabetes secondary to haemochromatosis is caused by or associated with the deposition of iron in the liver and the pancreas. This can lead to insulin resistance and glucose intolerance and to degenerative to the cells in the pancreas responsible for production insulin.

Hypogonadism (diminished sexual function):
This can cause reduced sex drive, cessation of menstruation (periods) in women and impotence in men.

Hypothyroidism:
Iron affects the thyroid gland and causes hypothyroidism, which slows down the body processes. Weight gain and tiredness are some of the signs of this problem if tiredness is persistent after removal of iron this disorder should be considered. Treatment for these problems varies and can include hormone replacement therapy.

Abdominal pain:
Abdominal pain is a frequent complaint and may described as an aching to a moderate pain sensation. The abdominal pain is located in the right upper quadrant, just above the stomach. Chest and back are occasionally also sites of pain. Often no cause is found or it can be related to liver damage.

Mood swings, systemic / non-specific problems, fatigue, malaise, weakness:
Most of these symptoms are found in other disorders. Chronic fatigue may be ascribed to after-effects of a viral infection or to psychological causes, and abdominal pain to irritable bowel syndrome. Similarly liver disorders may be put down to excessive alcohol intake, even in someone who is only a moderate drinker. However, if the same symptoms are present, GH. should also be considered as a diagnosis.

Most individuals who have GH. will, in due course, develop at least one or two of the above symptoms, although possibly in a milder form. There may be a long phase of the condition where there are no symptoms. However, if arthritis is found only in the first two finger joints this is highly suggestive of GH.

The need of treatment to remove excess iron does not depend upon the present of clinical symptoms. The risk of development of a serious complaint such as cirrhosis is much too great to be overlooked.


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Diagnosis

Genetic Haemochromatosis (GH), is diagnosed through blood which your Doctor can order, they are not routine blood tests.

1. Transferrin Saturation (TS) – indicates how much iron is readily available for use in the body. The average is 30% (slightly higher in men than women). If on two occasions this is over 50% in men or 45% in women, GH is very likely. This test is not often requested but it is the most specific and sensitive test for GH.

2. Serum Ferritin (SF) – indicates the amount of iron stored in the body. Levels significantly over 300μg/l [micrograms per litre] in men and post menopausal women and 200μg/l in younger women suggest GH. In the early stages of iron accumulation serum ferritin may be normal.

3. Gene Test – a simple blood test for the HFE gene mutation is positive in over 95% of people with GH. It will identify family members at risk of loading iron even before they have increased body iron stores.

4. Liver Biopsy – this is only usually requested if GH is diagnosed by the gene test and the serum ferritin level is over 1000μg/l, the liver function tests are abnormal, or the gene test is negative. A biopsy shows if the liver is damaged. If tests indicate GH is likely a referral to a Haematologist (blood specialist) or Gastroenterologist (Digestive system specialist) is usually the next step.


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Treatment

Treatment is simple and effective, and consists of regular removal of blood. Known as venesection therapy or phlebotomy, the procedure is the same as for blood donors. Each pint of blood removed contains 200mg of iron. The body then uses some of the excess stored iron to make new red blood cells.

Initially venesection will usually be performed around once a week, and continues until the iron level is satisfactory, which may be a year or more. During the course of treatment the size of the remaining iron stores is monitored.

Treatment should usually continue until the SF level reaches 20μg/l, indicating minimal or absent iron stores. After the stores have been depleted a second phase of treatment is usually required. Iron levels should be monitored regularly, and if necessary occasional venesections continued to keep iron levels down.

The TS should be maintained below 50% and the SF below 50μg/l

Early diagnosis and treatment is vital. Venesection leads to the reduction in the body’s stores of iron to the normal range, and many symptoms will improve. Providing this begins before cirrhosis has developed life expectancy will be normal. It will not cure some serious conditions caused by iron overload such as diabetes or cirrhosis if they are already present at the time treatment is started.


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Inheritance

To develop GH a defective HFE gene must be inherited from both parents. People who have inherited a defective gene from only one parent are carriers and will not usually be at risk of iron overload. Their children will have a 1 in 2 chance of also being carriers. If both parents are carriers, their children will have a 1 in 2 chance of being carriers and a 1 in 4 chance of being at risk of developing GH. It is estimated that 1 in 8 people in the UK are carriers.

If both parents are carriers:
On average a quarter of the children will develope haemochromatosis, half will be carriers, and a quarter will be normal.

If one parent has GH and the other is a carrier:
On average half the children will develop GH and the other half will be carriers.

If both parents suffer from GH:
All the children will inherit two defective genes and are more likely to develop GH.

Haemochromatosis and Family:
Because GH is inherited it can be passed on from parents to children. When one member of the household is diagnosed close relatives should be informed so that they can get themselves tested. Discuss this with your doctor.

If both parents suffer from GH:
All the children will inherit two defective genes and are more likely to develop GH.


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Living with haemochromatosis

It is not possible to eliminate iron overload by a low iron diet because many foods contain iron. A balanced diet of good lean meats, fruits, vegetables and grains that are not heavily fortified with iron is recommended.

The rate of iron aborption can be slowed by:

  • Avoiding vitamin supplements or tonics containing iron. Vitamin C enhances absorption of iron.
  • Bacteria: Raw shellfish such as oysters can be infected with a bacteria called Vibrio Vulnificus, which can be deadly to a person with high iron.
  • Limited alcohol intake, particularly with meals. Alcohol enhances absorption of iron and contributes to liver disease.
  • Tobacco smoke contains iron and is absorbed directly into the blood.
  • Water: being properly hydrated, especially during the therapeutic removal of blood, will reduce the amount of time it takes to remove a unit of blood. Also a person will not run the risk of becoming dehydrated following therapy. Note that some well water contains iron.

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