Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
Hereditary hemochromatosis is an inherited (genetic) disorder in which there is excessive accumulation of iron in the body (iron overload). It is a common genetic disorder among Caucasians in the United States, affecting approximately 1 to 6 people in the United States. Individuals affected with hereditary hemochromatosis may have no symptoms or signs (and have normal longevity), or they can have severe symptoms and signs of iron overload that include sexual dysfunction, heart failure, joint pains, cirrhosis of the liver, diabetes, fatigue, and darkening of skin.
The normal iron content of the body is three to four grams. The total amount of iron in the body is carefully controlled. The body loses one mg of iron daily from sweat and cells that are shed from the skin and the inner lining of the intestines. Women also lose one mg of iron daily on average from menstruation. In normal adults the intestines absorb one mg of iron daily from food to replace the lost iron, and therefore, there is no excess accumulation of iron in the body. When iron losses are greater, more iron is absorbed from food.
In individuals with hereditary hemochromatosis, the daily absorption of iron from the intestines is greater than the amount needed to replace losses. Since the normal body cannot increase iron excretion, the absorbed iron accumulates in the body. At this rate of iron accumulation, a man with hemochromatosis can accumulate 20 gram of total body iron by age 40 to 50. This excess iron deposits in the joints, liver, testicles, and heart, causing damage to these organs and signs and symptoms of hemochromatosis. Women with hemochromatosis accumulate iron at a slower rate than men because they lose more iron than men due to iron loss from menstruation and breastfeeding. Therefore, they typically develop signs and symptoms of organ damage due to excess iron 10 years later than men.
The heart is a two-stage electric pump whose job it is to circulate blood through the body. The initial electrical impulse that begins the process of a heartbeat is generated by a group of cells located in the "...