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$Unique_ID{BRK03806}
$Pretitle{}
$Title{Hemochromatosis, Hereditary}
$Subject{Hemochromatosis, Hereditary Bronze Diabetes Cirrhosis, congenital
pigmentary Familial Hemochromatosis Hemochromatosis Syndrome Hemosiderosis
Iron Overload Disease Sideroblastic Anemia Troisier-Hanot-Chauffard Syndrome}
$Volume{}
$Log{}
Copyright (C) 1984, 1985, 1987, 1988, 1990, 1991, 1992, 1993 National
Organization for Rare Disorders, Inc.
13:
Hemochromatosis, Hereditary
** IMPORTANT **
It and is possible that the main title of the article (Hemochromatosis)
Hereditary is not the name you expected. Please check the SYNONYMS listing
to find the alternate name and disorder subdivisions covered by this article.
Synonyms
Bronze Diabetes
Cirrhosis, congenital pigmentary
Familial Hemochromatosis
Hemochromatosis Syndrome
Hemosiderosis
Iron Overload Disease
Iron Retention
Primary Hemochromatosis
Information on the following diseases can be found in the Related
Disorders section of this report:
Sideroblastic Anemia
Troisier-Hanot-Chauffard Syndrome
General Discussion
**REMINDER **
The Information contained in the Rare Disease Database is provided for
educational purposes only. It should not be used for diagnostic or treatment
purposes. If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.
Hereditary Hemochromatosis is a metabolic disorder characterized by
excessive absorption of iron. The high accumulation of iron eventually
damages numerous organs. Involvement of the liver, pancreas or heart may
lead to serious complications, particularly in older patients. Joints and
skin may also become diseased.
Symptoms
The symptoms of Hereditary Hemochromatosis usually develops in men between
the ages of 40 and 60 years and later in women although the disorder can be
diagnosed much earlier. The symptoms vary according to the organs involved.
There may be no symptoms in the early years except for a healthy skin
coloring that resembles a suntan. Early symptoms may include weakness,
weight loss, apathy, loss of sexual drive (libido), and pain in the arms and
legs. Muscle tenderness and cramps in the legs may also develop. Symptoms
may occur earlier in men than in women because women lose blood during
menstruation and childbirth. When blood is lost, iron levels in the body are
reduced.
Later stages of the disease are characterized by cirrhosis of the liver.
Cirrhosis is a progressive illness in which the liver becomes covered with
fiberlike tissue and eventually this causes a marked decrease in liver
function. Enlargement of the liver may begin years before it becomes
impaired. Eventually this organ becomes firm and smooth, with excess iron
deposits within the liver cells.
Untreated Hereditary Hemochromatosis may also cause diabetes, gradual
darkening of the skin and congestive heart failure. Cancer of the liver is
more common than in the general population.
When the heart muscle is involved, the heart may become enlarged and have
an irregular beat (arrhythmias). An accumulation of fluid around the heart
may result in congestive heart failure. Involvement of the pituitary gland
can cause the malfunction of a variety of other endocrine glands (secondary
dysfunction) that the pituitary normally controls. These may include the
thyroid gland whose malfunctioning may cause an increased sensitivity to
cold. There may be an insufficient amount of adrenocorticoids causing
weakness and a lack of resistance to stress. A malfunction of the sex
glands (the testes in men and the ovaries in women) may also cause a wasting
away of the testicles (testicular atrophy), loss of sexual drive (libido) or
missed menstruation (amenorrhea).
Causes
Hemochromatosis is inherited as an autosomal recessive trait. Human traits,
including the classic genetic diseases, are the product of the interaction of
two genes, one received from the father and one from the mother. In
recessive disorders, the condition does not appear unless a person inherits
the same defective gene for the same trait from each parent. If one receives
one normal gene and one gene for the disease, the person will be a carrier
for the disease, but usually will not show symptoms. The risk of
transmitting the disease to the children of a couple, both of whom are
carriers for a recessive disorder, is twenty-five percent. Fifty percent of
their children will be carriers, but healthy as described above. Twenty-five
percent of their children will receive both normal genes, one from each
parent, and will be genetically normal.
Hereditary Hemochromatosis is expressed fully in individuals who are
homozygous for the defective gene since they have two identical disease genes
at the same location on matched chromosomes. People who are heterozygous
(have only one defective gene) may develop Hemochromatosis only if they have
diabetes, are alcoholic or have some other precipitating factor.
Heterozygous means a condition in which a person has two different genes
at the same place on matched chromosomes. An individual who is heterozygous
for a particular trait has inherited a gene for that trait from one parent
and the normal gene from the other parent. An individual heterozygous for a
hereditary disorder produced by a recessive gene will not show the disease or
will have a milder form of it.
The exact enzyme that is lacking in Hereditary Hemochromatosis is not
known. Relatives of an individual who has this disease can be diagnosed
using tissue typing. This test is very expensive and generally not practical
for the general population. Doctors can measure the level of transferrin in
the blood to screen for this disease before damage is done to the organs.
Transferrin is a protein in the blood that carries iron. This test is
inexpensive.
The defective gene that causes Hereditary Hemochromatosis has been
located on the short arm of chromosome 6 close to HLA-A (6p21.3). Genetic
testing can be performed to identify carriers of the gene.
Affected Population
It has been estimated that Hereditary Hemochromatosis may affect as many as
600,000 to 1.6 million Americans. Statistics indicate that as many as five
in 1000 white persons in the United States are affected by the disorder.
There may be as many as 24 to 32 million carriers. However, the disorder is
rarely diagnosed. Fewer than 250,000 cases have been identified in the
United States. Many patients are diagnosed on autopsy because they appear to
be healthy adults who die suddenly. Identification of affected individuals
signals that their relatives should be tested.
Related Disorders
Symptoms of the following disorder can be similar to those of Hereditary
Hemochromatosis. Comparisons may be useful for a differential diagnosis.
Sideroblastic Anemia is a rare disorder of the blood that is
characterized by the abnormal production of hemoglobin. Hemoglobin
production is low due to insufficient or ineffective use of iron, which may
be in abundant supply. The major symptoms include general weakness, fatigue
and difficulty breathing. Exertion may cause chest pains resembling angina.
The mucous membranes and the skin on the hands and arms may be pale, often
with a lemon-yellow cast. On occasion, bleeding that occurs under the skin
produces a brownish-red coloration of the skin. The spleen and liver may
become enlarged. (For more information on this disorder, choose
"Sideroblastic Anemia" as your search term in the Rare Disease Database.)
Therapies: Standard
Once the diagnosis of Hereditary Hemochromatosis is made, organ damage can be
prevented by removal of iron through repeated removal of blood from a vein
(phlebotomy). This is the standard means of removing excess iron from the
body. The earlier in the course of the disease this is instituted, the
better the prognosis. In cases where repeated phlebotomy causes anemia,
injections of deferroxamine (Desferroxamine) may allow reduction of iron
levels without producing anemia. Secondary disorders are treated
symptomatically.
Therapies: Investigational
In 1990 Dr. Gary M. Brittenham was given a grant from the FDA Office of
Orphan Products Development for his work on the pharmokinetics of Oral PIH
Chelation in Iron Overload Disease (Hemochromatosis). Dr. Brittenham is with
the Cleveland Metropolitan General Hospital in Cleveland, OH.
This disease entry is based upon medical information available through
June 1993. Since NORD's resources are limited, it is not possible to keep
every entry in the Rare Disease Database completely current and accurate.
Please check with the agencies listed in the Resources section for the most
current information about this disorder.
Resources
For more information on Hereditary Hemochromatosis, please contact:
National Organization for Rare Disorders (NORD)
P.O. Box 8923
New Fairfield, CT 06812-1783
(203) 746-6518
Hereditary Hemochromatosis Research Foundation
P.O. Box 8569
Albany, NY 12208
(518) 489-0972
Iron Overload Diseases Association
224 Datura Street, Suite 911
West Palm Beach, FL 33401
(407) 659-5616
National Digestive Diseases Information Clearinghouse
Box NDDIC
Bethesda, MD 20892
(301) 468-6344
For Genetic Information and Genetic Counseling Referrals:
March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains, NY 10605
(914) 428-7100
Alliance of Genetic Support Groups
35 Wisconsin Circle, Suite 440
Chevy Chase, MD 20815
(800) 336-GENE
(301) 652-5553
References
THE MERCK MANUAL 15th ed: R. Berkow, et al: eds; Merck, Sharp & Dohme
Research Laboratories, 1987. Pp. 942-4.
MENDELIAN INHERITANCE IN MAN, 9th Ed.: Victor A. McKusick, Editor: Johns
Hopkins University Press, 1990. Pp. 1235-1238.
CECIL TEXTBOOK OF MEDICINE, 19th Ed.: James B. Wyngaarden, and Lloyd H.
Smith, Jr., Editors; W.B. Saunders Co., 1990. Pp. 1133-1136.
BIRTH DEFECTS ENCYCLOPEDIA, Mary Louise Buyse, M.D., Editor-In-Chief;
Blackwell Scientific Publications, 1990. Pp. 856-858.
OVERVIEW OF HEMOCHROMATOSIS, L.H. Smith, Jr.; West J Medicine (Sept.
1990; 153(3)): Pp. 296-308.
IDIOPATHIC HEMOCHROMATOSIS, T.B. Kinney and S.A. DeLuca; Am Fam Physician
(Sept. 1991 44(3)): Pp. 873-875.
IMMUNOGENETICS OF HEREDITARY HEMOCHROMATOSIS, C.F. Bryan; Am Journal of
Medical Science (Jan 1991 301(1)): Pp. 47-49.