Hemochromatosis causes the body to absorb and store too much iron. The extra iron builds up in the body’s organs and damages them.
Iron is an essential nutrient found in many foods. The greatest amount is found in red meat and iron-fortified breads and cereals. In the body, iron becomes part of hemoglobin, a molecule in the blood that transports oxygen from the lungs to all body tissues.
Healthy people usually absorb about 10 percent of the iron contained in the food they eat, which meets normal dietary requirements. People with hemochromatosis absorb up to 30 percent of iron. Over time, they absorb and retain between five to 20 times more iron than the body needs. Because the body has no natural way to rid itself of the excess iron, it is stored in body tissues, specifically the liver, heart, and pancreas.
Types of hemochromatosis include:
Hereditary hemochromatosis is mainly caused by a defect in a gene called HFE, which helps regulate the amount of iron absorbed from food. The two known mutations of HFE are C282Y and H63D. C282Y is the most important. In people who inherit C282Y from both parents, the body absorbs too much iron and hemochromatosis can result.
Those who inherit the defective gene from only one parent are carriers for the disease but usually do not develop it; however, they still may have higher than average iron absorption.
Neither juvenile hemochromatosis nor neonatal hemochromatosis are caused by an HFE defect. Juvenile and neonatal hemochromatosis are caused by a mutation in a gene called hemojuvelin.
Hereditary hemochromatosis is one of the most common genetic disorders in North America. It most often affects Caucasians of Northern European descent, although other ethnic groups are also affected. About five people out of 1,000 of the North American Caucasian population carry two copies of the hemochromatosis gene and are susceptible to developing the disease. One out of every 8 to 12 people is a carrier of one abnormal gene. Hemochromatosis is less common in African Americans, Asian Americans, Hispanics/Latinos, and American Indians.
Although both men and women can inherit the gene defect, men are more likely than women to be diagnosed with hereditary hemochromatosis at a younger age. On average, men develop symptoms and are diagnosed between 30 to 50 years of age. For women, the average age of diagnosis is about 50.
Common symptoms include:
However, many people have no symptoms when they are diagnosed.
If the disease is not detected and treated early, iron may accumulate in body tissues and eventually lead to serious problems such as:
Blood tests can determine whether the amount of iron stored in the body is too high. The transferrin saturation test reveals how much iron is bound to the protein that carries iron in the blood. Transferrin saturation values higher than 45 percent are considered too high.
The total iron binding capacity test measures how well your blood can transport iron, and the serum ferritin test shows the level of iron in the liver. If either of these tests shows higher than normal levels of iron in the body, doctors can order a special blood test to detect the HFE mutation, which will confirm the diagnosis. If the mutation is not present, hereditary hemochromatosis is not the reason for the iron buildup and the doctor will look for other causes.
Hemochromatosis is considered rare and doctors may not think to test for it. Thus, the disease is often not diagnosed or treated. The initial symptoms can be diverse, vague, and mimic the symptoms of many other diseases. The doctors also may focus on the conditions caused by hemochromatosis—arthritis, liver disease, heart disease, or diabetes—rather than on the underlying iron overload. However, if the iron overload caused by hemochromatosis is diagnosed and treated before organ damage has occurred, a person can live a normal, healthy life.
Treatment cannot cure the conditions associated with established hemochromatosis, but it will help most of them improve. The main exception is arthritis, which does not improve even after excess iron is removed.
The first step of treatment is to rid the body of excess iron. This process is called phlebotomy, which means removing blood the same way it is drawn from donors at blood banks. Based on the severity of the iron overload, a pint of blood will be taken once or twice a week for several months to a year, and occasionally longer. Blood ferritin levels will be tested periodically to monitor iron levels. The goal is to bring blood ferritin levels to the low end of normal and keep them there. Depending on the lab, that means 25 to 50 micrograms of ferritin per liter of serum.
Once iron levels return to normal, maintenance therapy begins, which involves giving a pint of blood every 2 to 4 months for life. Some people may need phlebotomies more often. An annual blood ferritin test will help determine how often blood should be removed. Regular follow-up with a specialist is also necessary.
If treatment begins before organs are damaged, associated conditions—such as liver disease, heart disease, arthritis, and diabetes—can be prevented. The outlook for people who already have these conditions at diagnosis depends on the degree of organ damage. For example, treating hemochromatosis can stop the progression of liver disease in its early stages, which leads to a normal life expectancy. However, if cirrhosis, or scarring of the liver, has developed, the person’s risk of developing liver cancer increases, even if iron stores are reduced to normal levels.
People with hemochromatosis should not take iron or vitamin C supplements. And those who have liver damage should not consume alcoholic beverages or raw seafood because they may further damage the liver.