What Causes Hemochromatosis?
There are two types of hemochromatosis: primary and
secondary. Each type has a different cause.
Primary Hemochromatosis
A defect in the genes that control how much iron you
absorb from food causes primary hemochromatosis. This form of the disease is
sometimes called hereditary or classical hemochromatosis. Primary
hemochromatosis is the most common type of the disease.
The genes usually involved in primary
hemochromatosis are called HFE genes. Faulty HFE genes cause the body to absorb
too much iron. If you inherit two copies of the faulty HFE gene (one from each
parent), you're at risk for iron overload and signs and symptoms of
hemochromatosis.
If you inherit one faulty HFE gene and one normal
HFE gene, you're a "hemochromatosis carrier." Carriers usually don't develop
the disease. However, they can pass the faulty gene on to their children.
Estimates suggest that about 1 in 10 people in the United States are
hemochromatosis carriers.
If two parents are carriers of the faulty HFE gene,
then each of their children has a 1 in 4 chance of inheriting two faulty
HFE genes.
Although less common, other abnormal genes also can
cause hemochromatosis. Researchers continue to study what changes to normal
genes may cause the disease.
Secondary Hemochromatosis
This type of hemochromatosis usually is the result
of another disease or condition that causes iron overload. Examples of such
diseases and conditions include:
- Certain types of
anemia,
such as
thalassemias
and sideroblastic anemia
- Atransferrinemia and aceruloplasminemiaboth
are rare, inherited diseases
- Chronic liver diseases, such as chronic hepatitis
C infection, alcoholic liver disease, or nonalcoholic steatohepatitis
Other factors also can cause secondary
hemochromatosis, including:
- Blood
transfusions
- Oral iron pills or iron injections, with or
without very high vitamin C intake (vitamin C helps your body absorb iron)
- Long-term kidney dialysis
|