Originally published in The Ottawa Citizen February 19, 2002
Original Title: Hemochromatosis: Pumping (too much) iron
When the body absorbs too much iron, the result can be diabetes, heart failure, cirrhosis and sex organ failure.
Hereditary hemochromatosis is a disorder of iron metabolism affecting one in 300 North Americans genetically predisposed to develop iron overload.
It is under-diagnosed, yet can cause diabetes, heart failure, cirrhosis (scarring and shrinkage) and cancer of the liver, joint damage, and testicular and ovarian function failure. Early detection and treatment can prevent these complications.
The small intestine absorbs iron but the body has no mechanism to excrete it. The body’s iron content is about three to four grams and is normally in balance.
In hereditary hemochromatosis, iron accumulates over decades to 20 grams or more due to increased iron absorption by the small intestine. It deposits in the liver, pancreas, pituitary gland, joints and heart.
Women with the disorder usually develop iron overload symptoms several years after menopause. Men are five to 10 times more likely to manifest the disease. Seventy per cent develop symptoms between ages 40 to 60.
The disease occurs when a recessive (non-dominant) mutated gene passes from both parents to their children.
Symptoms include general weakness, enlarged liver, bronze skin pigmentation, abdominal pain, joint pain, loss of sex drive, no periods, loss of body hair, shortness of breath on exertion and symptoms of diabetes. The heart can become diffusely enlarged.
In advanced stages of the disease, worsening skin pigmentation, enlarged spleen, joint damage, cardiac arrhythmias, congestive heart failure, shrinking testicles and jaundice occur.
Organ damage occurs commonly after age 30. By the fourth or fifth decade of life, the liver is the first organ affected 95 per cent of the time followed by skin (90 per cent).
Simple blood tests can accurately diagnose hereditary hemochromatosis 95 per cent of the time. A liver biopsy will confirm the presence of iron and cirrhosis (scarring and shrinkage of the liver). With the availability of a genetic test, biopsy is rarely indicated unless the diagnosis is uncertain or there is a suspicion of liver cancer.
Treatment involves the removal of excess body iron and supportive measures for damaged organs. About 25 grams of stored iron needs removal. Since 500 millilitres of blood contains 200 to 250 milligrams of iron, weekly phlebotomy (bloodletting) may be required for one to two years.
Then, a lifelong maintenance program of four to six phlebotomies per year is required to keep iron levels normal. Sufferers are advised to avoid alcohol, iron fortified foods, iron supplements and uncooked shellfish. When the iron normalizes, life expectancy approaches near-normal levels for people who have not suffered major organ damage.
The five-year survival rate increases from 33 to 89 per cent. Liver function improves, the skin colour fades and cardiac failure may be reversed. Diabetes improves in about 40 per cent of people. Unfortunately, joint pain, cirrhosis and sex organ damage is irreversible.
Three million Canadians carry the hereditary hemochromatosisgene. The disorder fulfils the World Health Organization criteria for population screening.
Since iron overload usually develops through the second to fourth decades of life, the onset of symptoms provides the most practical approach to diagnosis and treatment. Nevertheless the index of suspicion for this disease should be considered for those people of Northern European extraction, especially of Celtic origin and of Mediterranean descent.
Family history is important. All first-degree relatives of known carriers and sufferers of hereditary hemochromatosis should be tested. Every child of a sufferer is a carrier.
According to Dr. Gail Graham, a geneticist at CHEO, children should not necessarily be tested, as iron overload due to the disorder in children is extremely rare.
Under most circumstances, children with an affected parent should be offered iron testing and DNA testing when they are in their late teens.
For more information, contact the Ottawa-Gatineau Support Group of Canadian Hemochromatosis Society (Marjorie Lounder at 739-9277, Elaine Robinson at 521-589 or Sylvie Desjardins at 643-2096) or visit visit the Canadian Hemochromatosis Society Web site at www.cdnhemochromatosis.ca.
© Dr. Barry Dworkin 2002