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hemochromatosis





Hemochromatosis is a disease in which too much iron builds up in the body. This extra iron is toxic to the body and can damage the organs. If hemochromatosis is not treated, it can lead to illness or even death.

Most people with hemochromatosis inherit the condition from their parents. If you inherit two hemochromatosis genes, one from each parent, you will have the condition. These two abnormal genes cause your body to absorb more iron than usual from the diet.

Hemochromatosis is one of the most common inherited (genetic) diseases in the United States. Approximately 1 million people in the United States have the pair of hemochromatosis genes. But not everyone with the pair of hemochromatosis genes develops signs and symptoms of the disease. Estimates of how many people actually develop signs and symptoms of iron overload vary greatly. The estimates range as high as half of all people with the two hemochromatosis genes.


Effects on the body

In hemochromatosis, iron can build up in most of your body's organs, but especially in the liver, heart, and pancreas. When this happens, the iron can poison the organs and lead to organ failure.
  • Liver. Hemochromatosis can lead to enlargement, cirrhosis; scarring of the liver so it does not work properly), failure, or cancer of the liver.
  • Heart. Hemochromatosis can cause irregular heart rate or rhythm (arrhythmia) and lead to heart failure.
  • Pancreas. Hemochromatosis can lead to diabetes mellitus.

Characteristics of hemochromatosis

How serious the disease is varies from person to person. Some people never have any symptoms or complications, even with high iron levels. Others have serious side effects or die from the disease. Certain factors can affect how serious the disease is. For example, other genes, besides the hemochromatosis genes, may change or lessen the severity of the disease. Vitamin C in the diet can increase the amount of iron the body absorbs from food and make hemochromatosis worse. Alcohol use can increase liver damage and cirrhosis. Certain conditions, such as hepatitis, can damage or weaken the liver.


Outlook

The outlook for people with hemochromatosis depends on how much organ damage has already occurred at the time of diagnosis. Early diagnosis and treatment are important. Treatment may be able to prevent, delay, or sometimes reverse complications of the disease. Treatment may lead to higher energy levels and better quality of life. For people who are diagnosed and treated early, normal lifespans are possible. If left untreated, hemochromatosis can lead to severe organ damage and even death.





What causes hemochromatosis?

There are two types of hemochromatosis: primary (hereditary) and secondary. Each type has a different cause.


Primary hemochromatosis

A defect in the genes that control how much iron you absorb from your diet causes primary hemochromatosis. Primary hemochromatosis is sometimes called hereditary hemochromatosis or classical hemochromatosis. Most cases of hemochromatosis are primary hemochromatosis.

The genes most commonly involved in primary hemochromatosis are called HFE genes. Abnormal HFE genes cause the body to absorb too much iron. Humans inherit two copies of most of the genes in the body, one from each parent. You have primary hemochromatosis if you inherit two copies of the abnormal HFE gene, one from each parent.

If you inherit one abnormal HFE gene and one normal HFE gene, you are a hemochromatosis "carrier." Carriers do not usually develop the disease, but they can pass the abnormal gene on to their children. About 1 in 10 people in the United States are believed to be hemochromatosis carriers.

If both parents are carriers of the abnormal HFE gene, then each of their children has a 1 in 4 chance of inheriting a pair of abnormal HFE genes.

Other types of abnormal genes also can cause hemochromatosis, but less commonly. Scientists are still studying what other changes to normal genes may cause hemochromatosis.


Secondary hemochromatosis

This type of hemochromatosis is usually the result of another disease or condition that can cause iron overload. Diseases or conditions that may cause hemochromatosis include:
  • Certain anemias, such as thalassemia and aplastic anemia
  • A condition called African iron overload, which is a combination of an inherited disorder and diet
  • Atransferrinemia and aceruloplasminemia, both rare inherited diseases
  • Chronic liver disease, such as hepatitis, alcoholic liver disease, or nonalcoholic steatohepatitis ("steato" means fatty)
Secondary hemochromatosis can sometimes be caused by too much iron from:

Who is at risk for hemochromatosis?


Populations affected

Hemochromatosis is one of the most common inherited (genetic) diseases in the United States. Approximately 1 million people in the United States have the pair of hemochromatosis genes. Hemochromatosis is most common in Caucasians of northern European descent. It is rare in African Americans. It is more common in men than in women. Older people are more likely to develop the disease than younger people. In fact, signs and symptoms do not usually appear in men until ages 40 to 60. In women, signs and symptoms do not usually appear until after the age of 50 (after menopause). Young children rarely develop hemochromatosis.


Major risk factors

Having a pair of abnormal HFE genes (one from each parent) is the major risk factor for hemochromatosis. However, many people with two copies of the abnormal gene do not develop signs or symptoms of the disease.


Other risk factors

Alcoholism is a risk factor for hemochromatosis. A family history of certain diseases also indicates a higher risk for hemochromatosis. Some of these diseases are heart attack, liver disease, diabetes, arthritis, and erectile dysfunction (impotence).


Signs and symptoms of hemochromatosis

Hemochromatosis can affect many parts of the body and can cause many different signs and symptoms. Many of the signs and symptoms are similar to those of other, more common diseases. Some people with the hemochromatosis genes may have no signs or symptoms at all.

Signs and symptoms of hemochromatosis usually are not seen until middle age. Men are more likely to develop complications such as diabetes or cirrhosis, and women are more likely to have general symptoms such as fatigue (tiredness). Signs and symptoms also vary based on how far the disease has advanced.

Common signs and symptoms of early-stage hemochromatosis include:
  • Fatigue
  • Joint pain
  • General weakness
  • Weight loss
  • Abdominal pain
  • Palpitations (a fluttering sensation in the chest)
Common signs and symptoms of mid-stage hemochromatosis (as more iron builds up in the body) include:
  • Joint damage and pain (arthritis)
  • Enlargement of the liver
  • Reproductive organ failure (for example, impotence, shrinkage of the testicles, loss of sex drive, infertility, absence of the menstrual cycle, and early menopause)
  • Heart problems (for example, chest pain, shortness of breath, and abnormal heart rhythms)
Common signs, symptoms, and conditions of advanced-stage hemochromatosis include:
  • Poor liver function (iron overload can lead to cirrhosis, failure, or cancer of the liver)
  • A high blood sugar level (glucose intolerance or diabetes)
  • Chronic (frequent or repeated) abdominal pain
  • Severe fatigue
  • Poor hormone production of the pituitary and thyroid glands
  • Damage to the adrenal gland
  • Heart failure (iron overload can damage the heart muscle, leading to heart failure)
  • Changes in skin color (for example, yellowish skin, tan skin not caused by the sun, and reddish palms not caused by use of the hands)

Diagnosis

Hemochromatosis is diagnosed based on your medical and family history, a physical exam, and diagnostic tests and procedures. The disease is sometimes found during the diagnosis of other diseases or conditions such as arthritis, liver disease, diabetes, heart disease, and impotence.


Specialists involved

In addition to family doctors or internal medicine specialists, other kinds of doctors may be involved in diagnosing and treating hemochromatosis, including:
  • A cardiologist (heart specialist)
  • An endocrinologist (gland system specialist)
  • A hepatologist (liver specialist)
  • A gastroenterologist (gastrointestinal tract specialist)
  • A hematologist (blood disease specialist)
  • A rheumatologist (specialist in diseases of the joints and tissues)

Medical and family history

Your doctor may ask questions to learn more about your past medical history, current symptoms, and family medical history. Your doctor may ask questions about:
  • Current symptoms, including when they started and how severe they are
  • Possible causes of secondary hemochromatosis, such as taking too much iron (pills or injections) or vitamin C
  • Whether other members of your family have hemochromatosis
  • Whether other members of your family have a history of other medical problems or diseases related to hemochromatosis

Physical exam

During the physical exam, your doctor will listen to your heart for abnormal rhythms and check for arthritis, abnormal skin color, and an enlarged liver.


Diagnostic tests and procedures

Based on the results of your medical history and physical exam, your doctor may order one or several tests to diagnose hemochromatosis.


Blood tests

Blood tests are used to find out how much iron is in the body. But blood tests alone are not enough to diagnose hemochromatosis. Types of blood tests that may be used include:
  • Transferrin saturation (TS). A high TS level in your blood may indicate that you have hemochromatosis.
  • Serum ferritin level. The serum ferritin level may be tested if the TS level is high. A high serum ferritin level may mean that iron is building up in the organs of the body. If there is iron buildup in your organs, you may have hemochromatosis.
  • Serum iron level. This test checks the level of iron in your blood. The iron level in your blood can be normal even if you have hemochromatosis.
  • Liver function tests. These blood tests may be done to check the level of damage to your liver. Liver damage may indicate that you have hemochromatosis. If you have been diagnosed with hemochromatosis, these blood tests may show how far the disease has advanced.

Quantitative phlebotomy (blood removal)

This test may be done to check a diagnosis of hemochromatosis. A phlebotomy (fle-BOT-o-me) is a process similar to giving blood. You will usually have a series of several phlebotomies. Your blood is tested to show whether blood removal is helping to lower iron levels.


Liver biopsy

A liver biopsy can show how much iron is in your liver and can diagnose liver damage (fibrosis, cirrhosis, and cancer). During a liver biopsy, your doctor numbs the area and then removes a small sample of liver tissue using a needle. The tissue is then examined under a microscope. Liver biopsies are used less often in diagnosis than they used to be.


Magnetic resonance imaging

Magnetic resonance imaging (MRI) is a test that can show the amount of iron in your liver. MRI uses magnetic fields to show images of organs and structures inside the body. It provides more detail than an X-ray for some kinds of problems.


Superconducting quantum interference device

Superconducting quantum interference device (SQuID), like MRI, measures the amount of iron in your liver. It is available at only a few medical centers.


Genetic testing

Genetic testing can be done to show whether you have zero, one, or two copies of the abnormal HFE gene. The test is accurate in more than 8 out of 10 cases. It can identify people who have two copies of the abnormal gene, but it cannot predict which of these people will go on to develop iron overload disease. The most common HFE mutation is called C282Y, and a less frequent one is H63D. The test may overlook people who have hemochromatosis caused by other types of genes.

Genetic testing can be carried out in two ways. A cheek test is when a cotton swab is used to collect cells from the inside of the mouth. A whole blood test is when a sample of blood is drawn from a vein in the arm to be tested.

Genetic testing may be done with genetic counseling for couples planning to have a family when one or both parents have hemochromatosis or have a family history of the disease. The purpose is to show:
  • If one or both parent(s) carry the abnormal HFE gene
  • The likelihood of passing the HFE genes to their children

How is hemochromatosis treated?

Treatments for hemochromatosis include therapeutic phlebotomy, iron chelation therapy, changes in diet, and other treatments for complications.


Goals of treatment

The goals of treating hemochromatosis are to reduce the amount of iron in your body to normal levels, prevent or delay organ damage from iron overload, treat complications of the disease, and maintain normal iron levels over the long term (for life).


Therapeutic phlebotomy (periodic blood removal)

This type of treatment is used to remove iron from your body in a process very much like donating blood. Therapeutic phlebotomy generally begins soon after diagnosis. Blood removal can be done in blood donation centers, hospital donation centers, or a doctor's office.

Therapeutic phlebotomy is usually advised for people with very high serum ferritin levels and people who have signs and symptoms of hemochromatosis. In the first stage of treatment, about 1 pint of blood is removed once or twice a week. After iron levels return to normal, you may continue phlebotomy treatments but may need them much less often, typically every 3 months. As long as treatment continues, which is often for the rest of your life, the doctor will order lab tests often to check iron levels.


Iron chelation therapy

Iron chelation therapy uses medicine to remove excess iron from your body. It is a good option for people who cannot undergo repeated blood removal.

Injected iron chelation therapy can be done in the doctor's office. Oral iron chelation therapy can be taken at home. The medicines used for chelation therapy include:
  • Deferoxamine mesylate (Desferal®). This medicine is injected either in a muscle, under the skin, or through a vein.
  • Exjade® (Deferasirox). This is an oral medicine that binds with the extra iron and then leaves the body in the feces.
  • Experimental medicines. Deferiprone (Ferriprox®) is an oral medicine that binds with the extra iron and then leaves the body in the urine or feces.

Changes in diet

Your doctor may advise you to change your diet if you have hemochromatosis. You may be advised to:
  • Avoid taking iron (including iron pills, injections of iron, or multivitamins that contain iron).
  • Limit your intake of vitamin C. Vitamin C increases the amount of iron the body absorbs. You should take no more than 500 mg per day from nonfood sources such as pills.
  • Avoid uncooked fish and shellfish. Some fish and shellfish contain bacteria that could cause infection in people with hemochromatosis.
  • Limit alcohol intake. Drinking alcohol increases the risk for liver disease and can make liver disease worse.

Treatment for complications

Your doctor may provide other treatment as needed for complications such as liver disease, heart problems, or diabetes.


How can hemochromatosis be prevented?

If you have two copies of the hemochromatosis gene, you cannot prevent the development of iron overload disease. But not everyone who inherits the hemochromatosis genes develops iron overload disease. In people who do develop iron overload disease, treatments such as therapeutic phlebotomy (blood removal) can keep the disease from getting worse.

Primary (hereditary) hemochromatosis is passed from parents to children through the genes. Genetic testing and counseling can help parents with the hemochromatosis genes determine their chances of passing the genes on to their children.


Living with hemochromatosis


Information about outcomes

Hemochromatosis can be treated effectively with phlebotomy (repeated blood removal). How well the treatment works depends on how much organ damage has already occurred before treatment begins. If hemochromatosis is found and treated early, complications can be prevented, delayed, or even reversed. With early diagnosis and treatment, a normal lifespan is possible. When organ damage has already occurred, treatment may prevent further damage and improve life expectancy, but it may not be able to reverse existing damage. If not treated, hemochromatosis can lead to severe organ damage or even death.


What to expect after treatment

Different people have different responses to treatment. Some people undergoing frequent blood removal may feel fatigued (very tired). People who are in advanced stages of the disease or who are receiving aggressive (very strong) treatment that weakens them may need help with daily tasks and activities.

At first, frequent phlebotomies may be needed for anywhere from 6 months to 3 years. How long this treatment is needed depends on how much extra iron is in the body. Even after this, ongoing treatment may be needed two to six times a year to keep the iron from building back up again.


Ongoing health care needs

Ongoing medical needs may include:
  • Continuing phlebotomy
  • Taking medicines as prescribed
  • Contacting your doctor immediately about new or worsening symptoms, or about possible reactions to phlebotomy treatments
  • Following up regularly with your doctor about lab work to check iron levels, ongoing treatments, or annual exams
  • Using a diary or log to track iron levels
People having phlebotomies may need to change their usual work times to schedule treatments. They may also need to change work schedules to allow for periods of fatigue, especially when they are having aggressive treatment that weakens them.

Check with your doctor and insurance company about coverage for different treatments.

Screening for family members of people With hemochromatosis

Parents, grandparents, brothers and sisters, and children (blood relatives) of a person with hemochromatosis may be at risk for hemochromatosis. Checking iron levels in the blood of these relatives is advised. Genetic testing may be recommended to show who is at risk for the disease. If a relative has already been diagnosed as having iron overload, a genetic test can show whether the cause is genetic (inherited).


Related categories

   • HEALTH AND DISEASE

Source: National Heart, Lung, and Blood Institute