What is hemochromatosis? |

Causes and Symptoms

Iron
is used by the body for various processes, such as making hemoglobin, the oxygen-carrying molecule in blood. Hemochromatosis is an inherited disorder, usually caused by a mutation of the HFE gene, characterized by the excessive absorption and accumulation of iron from the diet. This excess iron is deposited in various organs. Damage to these organs from years of iron accumulation results in the symptoms of hemochromatosis. The most commonly affected organs are the pancreas (causing diabetes), the skin (causing bronzelike skin pigmentation), the joints (causing arthritis), the testes (causing loss of libido and erectile dysfunction), and the heart (causing abnormal heart rhythms or heart failure). The pituitary gland, which regulates sex hormones and metabolism, can also be affected. Although the liver is commonly involved as well, this usually results in mild abnormalities in blood tests of liver enzymes rather than liver failure. However, cirrhosis
of the liver can occur, and these patients are at risk for developing liver cancer. Unfortunately, most of the above warning symptoms occur late in the disease, after decades of iron accumulation and organ damage have already taken place.

Treatment and Therapy

Ideally, hemochromatosis should be detected and treated before the onset of symptoms. Screening for patients with a family history of this disease can be performed via blood tests, such as the iron saturation index. More recently, a genetic test for a common mutation that causes hemochromatosis has been developed. Liver biopsy is sometimes needed to confirm the diagnosis. Treatment consists of repeated phlebotomy, or the removal of blood. Typically one unit of blood is removed per week until the patient becomes mildly anemic. Hemochromatosis may require the removal of up to 150 units of blood over several years. Subsequently, phlebotomy is repeated every three to four months, and the patient’s iron stores (ferritin) are monitored. If phlebotomy is started before liver cirrhosis develops, then many complications can be avoided. Some patients may benefit from treatment with desferroxamine, a chelating agent that removes iron.

Perspective and Prospects

Hemochromatosis was initially described in 1865 as a triad of glucose in the urine, dark pigmentation of the skin, and liver cirrhosis. Research into the disease has resulted in tremendous advances in the understanding of iron metabolism. The HFE gene, responsible for most diagnoses of hemochromatosis, has been mapped to chromosome 6. Although the genetic defect is present in both men and women, men develop the disease much more often, since menstruation removes excess iron in women. A test to screen for one common mutation in this gene is available, but its usefulness is limited since several other mutations may cause the disease, especially in non-Caucasian ethnic groups.

Bibliography

Barton, James C., and Corwin Q. Edwards, eds. Hemochromatosis: Genetics, Pathophysiology, Diagnosis, and Treatment. New York: Cambridge University Press, 2000.

Everson, Gregory T., and Marilyn Olsen. Living with Hemochromatosis. New York: Hatherleigh Press, 2003.

Garrison, Cheryl D., ed. The Iron Disorders Institute Guide to Hemochromatosis. 2d ed. Naperville, Ill.: Cumberland House, 2009.

"Hemochromatosis." Mayo Clinic, December 13, 2012.

"Hemochromatosis." National Digestive Diseases Information Clearinghouse, May 10, 2012.

Parker, James N., and Philip M. Parker, eds. The Official Patient’s Sourcebook on Hemochromatosis. San Diego, Calif.: Icon Health, 2002.

Weinberg, E. D., and Cheryl D. Garrison. Exposing the Hidden Dangers of Iron: What Every Medical Professional Should Know About the Impact of Iron on the Disease Process. Nashville: Cumberland House, 2004.

"What Is Hemochromatosis?" National Heart, Lung, and Blood Institute, February 1, 2011.