Hemochromatosis
Hemochromatosis is a condition in which the body accumulates excess amounts of iron.
Serious and sometimes fatal health problems may result from the excess iron that accumulates in the body as a result of this genetic disorder. The excess iron slowly builds to toxic levels in tissues of major organs such as the liver, heart, brain, pancreas, lungs, and synovium (joints). These overburdened organs cease to function properly and eventually become diseased. Hereditary hemochromatosis (HHC) is one of the most common genetic diseases in humans, but it can be undiagnosed or misdiagnosed. Undiagnosed and untreated HHC can develop into diseases such as diabetes, heart trouble, arthritis, cirrhosis of the liver, neurological problems, depression, impotence, infertility, and liver cancer.
Iron build up in those with HHC is slow, usually taking years to build to destructive levels. HHC/Iron overload generally manifests in a male's early thirties and is diagnosed in a male's mid to late fifties. For this reason HHC has acquired the mistaken identity of an older male's disease. HHC can be present in females, adolescents and possibly in children.
Symptoms of Hemochromatosis
Symptoms associated with hemochromatosis most often appear in middle age, although some people may develop problems earlier. These symptoms reflect the tissue and organ damage that result from the disease. Not everyone manifests the same symptoms.
Early disease symptoms of hemochromatosis are nonspecific and can be misdiagnosed as arthritis, diabetes, depression, impotence, liver disease, and other better recognized conditions.
Symptoms most common in early stages of HHC include fatigue, heart palpitations, joint pain, non-specific stomach pain, impotence, and loss of menstrual periods. Abnormalities of liver function tests can also occur in the absence of other symptoms.
Later disease symptoms include gray or bronze skin pigmentation, cirrhosis of the liver, liver cancer, diabetes mellitus, hypopituitarism, decreased pituitary or gonadal function, heart disease or heart failure, joint disease, chronic abdominal pain, severe fatigue, and certain infections.
Excess iron in the diet, alcohol use, infections, iron lost through blood donations and menstruation, and other environmental factors may affect the clinical course of hemochromatosis. For example, alcohol use may worsen the disease, whereas iron lost through blood donations or menstruation may lessen the severity.
Diagnosis of Hemochromatosis
The gene for hemochromatosis, HFE, was identified in 1996. Studies of the gene indicate that the HFE mutation is relatively common. The CDC estimates that in the US as many one in every 200 to 500 people, or approximately one million people, have evidence of hemochromatosis, and as many as one in every 10 people may carry the gene for this hereditary disease. Other organizations have higher estimates or the prevalence of carriers and sufferers of hemochromatosis. Early detection of HHC is essential because the disease's potentially serious complications can be prevented by early therapy.
HHC can be detected by specific blood tests, genetic screening and by a liver biopsy. A sensitive and relatively inexpensive screening test for iron overload is the transferrin saturation test (serum iron divided by the total iron binding capacity). The diagnosis is most commonly confirmed by liver biopsy or by the systematic extraction of iron through blood removal. Currently, routine medical care or checkups usually do not include testing for hemochromatosis.
There has been debate among the medical profession about the usefulness of large scale genetic screening for HHC. As with all genetic testing there are benefits, but also serious drawbacks to DNA screening on a large scale. But physicians and researchers agree that people who have a close blood relative with HHC, as well as persons who have the signs and symptoms compatible with HHC, should talk with their health care provider about the possibility of being tested for the presence of one of the gene mutations associated with HHC.
According to the Iron Disorders Institute, the groups at highest risk for HHC inlcude:
- Males of Scotch-Irish, British, Dutch, German, French, Spanish, Italian, (Northern Western European), or Mediterranean descent, or with a family history of premature death by heart attack, liver disease, diabetes, arthritis, impotence, neurological disorders or cancer.
- Women who no longer have a period due to menopause, premature discontinuation of period or an hysterectomy and who have the same ancestry and family history listed above.
- Blood relatives of these men and women.
- Anyone homozygous for HFE gene mutations. However, evidence is mounting that indicates iron loading may occur in heterozygotes and compound heterozygotes as well, perhaps affecting the heart.
Treatment
Periodically removing blood to remove excess iron is a necessary component in treating hemochromatosis. The procedure is called a phlebotomy. In the initial phase of treatment, one unit of whole blood, which contains about 250 milligrams of iron, is removed, usually once or twice weekly. Phlebotomies are done at blood donation centers, as outpatient procedures at hospitals and also in doctors' offices. This "de-ironing" phase continues until all excess stored iron is removed, as indicated by monitoring hemoglobin and serum ferritin concentrations. The frequency and duration of this process can vary among patients by age, gender, reason for diagnosis, and severity of symptoms.
The second phase of treatment is long-term maintenance of normal iron stores. The frequency of blood removal in this phase is determined individually for each patient, according to symptoms and levels of hemoglobin and serum ferritin.
Questions Regarding Blood Donation
Frequently patients and their care providers ask whether it is safe for individuals with hemochromatosis to donate blood to community organizations. The Food and Drug Administration (FDA) recently announced that blood from therapeutic phlebotomies for persons with hemochromatosis could be used for transfusion if the blood donation facility met certain criteria: 1) the blood collection center may not charge for the therapeutic phlebotomy and 2) the blood center must apply to FDA for exemption from existing regulations. As part of that exemption, the blood center must collect and submit specified data to the FDA. The FDA will consider exemption applications on a case-by-case basis. Additional questions regarding blood donation from patients
with hemochromatosis should be referred to the FDA.
Prognosis
The degree of organ damage from iron overload at the time of diagnosis is the major determinant of a person's prognosis. For a person who has no evident tissue or organ damage, proper management of the disease may result in a normal long-term outcome and life expectancy. For a person who has evident tissue or organ damage, further damage can be halted, but damage already incurred may not be reversible.
Research priorities aimed at future prevention and control of hemochromatosis include (1) determining the proportion of people with hemochromatosis who will become symptomatic and (2) evaluating the risks, benefits, and effectiveness of different methods of case detection and follow-up. Educating health care providers and patients about hemochromatosis is central to the public health plan of action.
Article Created: 2000-11-20
Article Updated: 2000-12-01
Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.
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