Primary hemochromatosis is the most common genetic disorder in the US, affecting an estimated 1 of every 200-300 Americans. Similar symptoms may occur from the secondary form of hemochromatosis, which can be caused by other diseases such as thalassemia or sideroblastic anemia. Hemochromatosis may also be caused by having a large number of blood transfusions, particularly in patients who get them for inherited or pre-malignant anemias. Occasionally, it may be seen with hemolytic anemia, porphyria cutanea tarda, excessive oral iron ingestion, and chronic alcoholism.

First, excess iron accumulates in the liver and causes liver enlargement. Then, other organs are affected. The disease may lead to the development of diabetes, skin pigment changes, cardiac problems, arthritis, testicular atrophy, cirrhosis of the liver, liver cancer, hypopituitarism, chronic abdominal pain, severe fatigue, and increased risk of certain bacterial infections.

Hemochromatosis affects men five times more frequently than women. It is particularly common in Caucasians of Western European descent. Symptoms are often seen in men between the ages of 30 and 50 and in women over 50 (although some people may develop problems by age 20). Alcoholism and a family history of hemochromatosis are risk factors.