Health
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| Hemochromatosis |
What are Hemochromatosis?
Hemochromatosis, the most common form of iron overload
disease, is an inherited disorder that causes the body to
absorb and store too much iron. The extra iron builds up in
organs and damages them. Without treatment, the disease
can cause these organs to fail.
Iron is an essential nutrient found in many foods. The greatest
amount is found in red meat and iron-fortified bread and
cereal. In the body, iron becomes part of hemoglobin, a
molecule in the blood that transports oxygen from the lungs to
all body tissues.
Healthy people usually absorb about 10 percent of the iron
contained in the food they eat to meet the body needs. People
with hemochromatosis absorb more than the body needs. The
body has no natural way to rid itself of the excess iron, so it is
stored in body tissues, especially the liver, heart, and pancreas.
Causes
Genetic or hereditary hemochromatosis is mainly associated
with a defect in a gene called HFE, which helps regulate the
amount of iron absorbed from food. There are two known
important mutations in HFE, named C282Y and H63D. C282Y is
the most important. When C282Y is inherited from both
parents, iron is overabsorbed from the diet and
hemochromatosis can result. H63D usually causes little
increase in iron absorption, but a person with H63D from one
parent and C282Y from the other may rarely develop
hemochromatosis.
The genetic defect of hemochromatosis is present at birth, but
symptoms rarely appear before adulthood. A person who
inherits the defective gene from both parents may develop
hemochromatosis. A person who inherits the defective gene
from only one parent is a carrier for the disease but usually
does not develop it. However, carriers might have a slight
increase in iron absorption.
Juvenile hemochromatosis and neonatal hemochromatosis are
two forms of the disease that are not caused by an HFE defect.
Their cause is unknown. The juvenile form leads to severe iron
overload and liver and heart disease in adolescents and young
adults between the ages of 15 and 30, and the neonatal form
causes the same problems in newborn infants.
Risk Factors
Hereditary hemochromatosis is one of the most common
genetic disorders in the United States. It most often affects
Caucasians of Northern European descent, although other
ethnic groups are also affected. About 5 people in 1,000 (0.5
percent) of the U.S. Caucasian population carry two copies of
the hemochromatosis gene and are susceptible to developing
the disease. One person in 8 to 12 is a carrier of the abnormal
gene. Hemochromatosis is less common in African Americans,
Asian Americans, Hispanic Americans, and American Indians.
Although both men and women can inherit the gene defect,
men are about five times more likely to be diagnosed with the
effects of hereditary hemochromatosis than women. Men also
tend to develop problems from the excess iron at a younger
age.
Symptoms
Joint pain is the most common complaint of people with
hemochromatosis. Other common symptoms include fatigue,
lack of energy, abdominal pain, loss of sex drive, and heart
problems. Symptoms tend to occur in men between the ages
of 30 and 50 and in women over age 50. However, many
people have no symptoms when they are diagnosed.
If the disease is not detected early and treated, iron may
accumulate in body tissues and may eventually lead to serious
problems such as arthritis, liver disease, damage to the
pancreas, possibly causing diabetes, heart abnormalities,
impotence, early menopause, abnormal pigmentation of the
skin, thyroid deficiency and damage to the adrenal gland.
Diagnosis
A thorough medical history, a physical examination, and
routine blood tests help rule out other conditions that could be
causing the symptoms. This information often provides helpful
clues, such as a family history of arthritis or unexplained liver
disease.
Blood tests can determine whether the amount of iron stored
in the body is too high. The transferrin saturation test
determines how much iron is bound to the protein that carries
iron in the blood. The total iron binding capacity (TIBC) test
measures how well your blood can transport iron. The serum
ferritin test shows the level of iron in the liver. If either of these
tests shows higher than normal levels of iron in the body,
doctors can order a special blood test to detect the HFE
mutation, which will help confirm the diagnosis. (If the mutation
is not present, hereditary hemochromatosis is not the reason
for the iron buildup, and the doctor will look for other causes.)
A liver biopsy, in which a tiny piece of liver tissue is removed
and examined under a microscope, may be needed. It will show
how much iron has accumulated in the liver and whether the
liver is damaged.
Hemochromatosis is often undiagnosed and untreated. It is
considered rare and doctors may not think to test for it. The
initial symptoms can be diverse and vague and can mimic the
symptoms of many other diseases. Also, doctors may focus on
the conditions caused by hemochromatosis—arthritis, liver
disease, heart disease, or diabetes—rather than on the
underlying iron overload. However, if the iron overload caused
by hemochromatosis is diagnosed and treated before organ
damage has occurred, a person can live a normal, healthy life.
Hemochromatosis is usually treated by a specialist in liver
disorders (hepatologist), digestive disorders
(gastroenterologist), or blood disorders (hematologist).
Because of the other problems associated with
hemochromatosis, several other specialists may be on the
treatment team, such as an endocrinologist, cardiologist, or
rheumatologist. Internists or family practitioners can also treat
the disease.
Treatment
Treatment is simple, inexpensive, and safe. The first step is to
rid the body of excess iron. The process is called phlebotomy,
which means removing blood the same way it is drawn from
donors at blood banks. Depending on how severe the iron
overload is, a pint of blood will be taken once or twice a week
for several months to a year, and occasionally longer. Blood
ferritin levels will be tested periodically to monitor iron levels.
The goal is to bring blood ferritin levels to the low end of
normal and keep them there. Depending on the lab, that
means 25 to 50 micrograms of ferritin per liter of serum.
Depending on the amount of iron overload at diagnosis,
reaching normal levels can take many phlebotomies.
Once iron levels return to normal, maintenance therapy, which
involves giving a pint of blood every 2 to 4 months for life,
begins. Some people may need it more often. An annual blood
ferritin test will help determine how often blood should be
removed.
The earlier hemochromatosis is diagnosed and treated in
appropriate cases, the better. If treatment begins before any
organs are damaged, associated conditions—such as liver
disease, heart disease, arthritis, and diabetes—can be
prevented. The outlook for people who already have these
conditions at diagnosis depends on the degree of organ
damage. For example, treating hemochromatosis can stop the
progression of liver disease in its early stages, which means a
normal life expectancy. However, if cirrhosis has developed, the
person's risk of developing liver cancer increases, even if iron
stores are reduced to normal levels. Appropriate regular follow-
up with a specialist is necessary.
People who have complications of hemochromatosis may want
to consider getting treatment from a specialized
hemochromatosis center. These centers are located
throughout the country. Information is available from the
organizations listed under For More Information.
People with hemochromatosis should not take iron
supplements. Those who have liver damage should not drink
alcoholic beverages because they may further damage the liver.
Although treatment cannot cure the conditions associated with
established hemochromatosis, it will help most of them. The
main exception is arthritis, which does not improve even after
excess iron is removed.
Tests for Hemochromatosis
Screening for hemochromatosis (testing people who have no
symptoms) is not a routine part of medical care or checkups.
However, researchers and public health officials do have some
suggestions:
* Brothers and sisters of people who have hemochromatosis
should have their blood tested to see if they have the disease
or are carriers.
* Parents, children, and other close relatives of people who
have the disease should consider testing.
* Doctors should consider testing people who have joint
disease, severe and continuing fatigue, heart disease, elevated
liver enzymes, impotence, and diabetes, because these
conditions may result from hemochromatosis.
Since the genetic defect is common and early detection and
treatment are so effective, some researchers and education
and advocacy groups have suggested that widespread
screening for hemochromatosis would be cost-effective and
should be conducted. However, a simple, inexpensive, and
accurate test for routine screening does not yet exist, and the
available options have limitations. For example, the genetic test
provides a definitive diagnosis, but it is expensive. The blood
test for transferrin saturation is widely available and relatively
inexpensive, but it may have to be done twice with careful
handling to confirm a diagnosis and to show that it is the
consequence of iron overload.
Content Source NIDDK.NIH
Hemochromatosis, the most common form of iron overload
disease, is an inherited disorder that causes the body to
absorb and store too much iron. The extra iron builds up in
organs and damages them. Without treatment, the disease
can cause these organs to fail.
Iron is an essential nutrient found in many foods. The greatest
amount is found in red meat and iron-fortified bread and
cereal. In the body, iron becomes part of hemoglobin, a
molecule in the blood that transports oxygen from the lungs to
all body tissues.
Healthy people usually absorb about 10 percent of the iron
contained in the food they eat to meet the body needs. People
with hemochromatosis absorb more than the body needs. The
body has no natural way to rid itself of the excess iron, so it is
stored in body tissues, especially the liver, heart, and pancreas.
Causes
Genetic or hereditary hemochromatosis is mainly associated
with a defect in a gene called HFE, which helps regulate the
amount of iron absorbed from food. There are two known
important mutations in HFE, named C282Y and H63D. C282Y is
the most important. When C282Y is inherited from both
parents, iron is overabsorbed from the diet and
hemochromatosis can result. H63D usually causes little
increase in iron absorption, but a person with H63D from one
parent and C282Y from the other may rarely develop
hemochromatosis.
The genetic defect of hemochromatosis is present at birth, but
symptoms rarely appear before adulthood. A person who
inherits the defective gene from both parents may develop
hemochromatosis. A person who inherits the defective gene
from only one parent is a carrier for the disease but usually
does not develop it. However, carriers might have a slight
increase in iron absorption.
Juvenile hemochromatosis and neonatal hemochromatosis are
two forms of the disease that are not caused by an HFE defect.
Their cause is unknown. The juvenile form leads to severe iron
overload and liver and heart disease in adolescents and young
adults between the ages of 15 and 30, and the neonatal form
causes the same problems in newborn infants.
Risk Factors
Hereditary hemochromatosis is one of the most common
genetic disorders in the United States. It most often affects
Caucasians of Northern European descent, although other
ethnic groups are also affected. About 5 people in 1,000 (0.5
percent) of the U.S. Caucasian population carry two copies of
the hemochromatosis gene and are susceptible to developing
the disease. One person in 8 to 12 is a carrier of the abnormal
gene. Hemochromatosis is less common in African Americans,
Asian Americans, Hispanic Americans, and American Indians.
Although both men and women can inherit the gene defect,
men are about five times more likely to be diagnosed with the
effects of hereditary hemochromatosis than women. Men also
tend to develop problems from the excess iron at a younger
age.
Symptoms
Joint pain is the most common complaint of people with
hemochromatosis. Other common symptoms include fatigue,
lack of energy, abdominal pain, loss of sex drive, and heart
problems. Symptoms tend to occur in men between the ages
of 30 and 50 and in women over age 50. However, many
people have no symptoms when they are diagnosed.
If the disease is not detected early and treated, iron may
accumulate in body tissues and may eventually lead to serious
problems such as arthritis, liver disease, damage to the
pancreas, possibly causing diabetes, heart abnormalities,
impotence, early menopause, abnormal pigmentation of the
skin, thyroid deficiency and damage to the adrenal gland.
Diagnosis
A thorough medical history, a physical examination, and
routine blood tests help rule out other conditions that could be
causing the symptoms. This information often provides helpful
clues, such as a family history of arthritis or unexplained liver
disease.
Blood tests can determine whether the amount of iron stored
in the body is too high. The transferrin saturation test
determines how much iron is bound to the protein that carries
iron in the blood. The total iron binding capacity (TIBC) test
measures how well your blood can transport iron. The serum
ferritin test shows the level of iron in the liver. If either of these
tests shows higher than normal levels of iron in the body,
doctors can order a special blood test to detect the HFE
mutation, which will help confirm the diagnosis. (If the mutation
is not present, hereditary hemochromatosis is not the reason
for the iron buildup, and the doctor will look for other causes.)
A liver biopsy, in which a tiny piece of liver tissue is removed
and examined under a microscope, may be needed. It will show
how much iron has accumulated in the liver and whether the
liver is damaged.
Hemochromatosis is often undiagnosed and untreated. It is
considered rare and doctors may not think to test for it. The
initial symptoms can be diverse and vague and can mimic the
symptoms of many other diseases. Also, doctors may focus on
the conditions caused by hemochromatosis—arthritis, liver
disease, heart disease, or diabetes—rather than on the
underlying iron overload. However, if the iron overload caused
by hemochromatosis is diagnosed and treated before organ
damage has occurred, a person can live a normal, healthy life.
Hemochromatosis is usually treated by a specialist in liver
disorders (hepatologist), digestive disorders
(gastroenterologist), or blood disorders (hematologist).
Because of the other problems associated with
hemochromatosis, several other specialists may be on the
treatment team, such as an endocrinologist, cardiologist, or
rheumatologist. Internists or family practitioners can also treat
the disease.
Treatment
Treatment is simple, inexpensive, and safe. The first step is to
rid the body of excess iron. The process is called phlebotomy,
which means removing blood the same way it is drawn from
donors at blood banks. Depending on how severe the iron
overload is, a pint of blood will be taken once or twice a week
for several months to a year, and occasionally longer. Blood
ferritin levels will be tested periodically to monitor iron levels.
The goal is to bring blood ferritin levels to the low end of
normal and keep them there. Depending on the lab, that
means 25 to 50 micrograms of ferritin per liter of serum.
Depending on the amount of iron overload at diagnosis,
reaching normal levels can take many phlebotomies.
Once iron levels return to normal, maintenance therapy, which
involves giving a pint of blood every 2 to 4 months for life,
begins. Some people may need it more often. An annual blood
ferritin test will help determine how often blood should be
removed.
The earlier hemochromatosis is diagnosed and treated in
appropriate cases, the better. If treatment begins before any
organs are damaged, associated conditions—such as liver
disease, heart disease, arthritis, and diabetes—can be
prevented. The outlook for people who already have these
conditions at diagnosis depends on the degree of organ
damage. For example, treating hemochromatosis can stop the
progression of liver disease in its early stages, which means a
normal life expectancy. However, if cirrhosis has developed, the
person's risk of developing liver cancer increases, even if iron
stores are reduced to normal levels. Appropriate regular follow-
up with a specialist is necessary.
People who have complications of hemochromatosis may want
to consider getting treatment from a specialized
hemochromatosis center. These centers are located
throughout the country. Information is available from the
organizations listed under For More Information.
People with hemochromatosis should not take iron
supplements. Those who have liver damage should not drink
alcoholic beverages because they may further damage the liver.
Although treatment cannot cure the conditions associated with
established hemochromatosis, it will help most of them. The
main exception is arthritis, which does not improve even after
excess iron is removed.
Tests for Hemochromatosis
Screening for hemochromatosis (testing people who have no
symptoms) is not a routine part of medical care or checkups.
However, researchers and public health officials do have some
suggestions:
* Brothers and sisters of people who have hemochromatosis
should have their blood tested to see if they have the disease
or are carriers.
* Parents, children, and other close relatives of people who
have the disease should consider testing.
* Doctors should consider testing people who have joint
disease, severe and continuing fatigue, heart disease, elevated
liver enzymes, impotence, and diabetes, because these
conditions may result from hemochromatosis.
Since the genetic defect is common and early detection and
treatment are so effective, some researchers and education
and advocacy groups have suggested that widespread
screening for hemochromatosis would be cost-effective and
should be conducted. However, a simple, inexpensive, and
accurate test for routine screening does not yet exist, and the
available options have limitations. For example, the genetic test
provides a definitive diagnosis, but it is expensive. The blood
test for transferrin saturation is widely available and relatively
inexpensive, but it may have to be done twice with careful
handling to confirm a diagnosis and to show that it is the
consequence of iron overload.
Content Source NIDDK.NIH
| MEDICAL NOTES |
DISEASES AND
CONDITIONS
Acidosis
Acne
Acromegaly
Addison's Disease
Adrenal Crisis
Age. macular degn
Alzheimer's disease
Autoimmune
Hepatitis
Barrett's Esophagus
Cancer
Constipation
Colon Polyps
Crohns Disease
Cushing's Syndrm.
Diabetes
Erectile Dysfunction
Fecal Incontinence
Gallstones
Gastritis
Gastroenteritis
Gastroesophageal
Reflux (GERD)
Growth Hormone
Def.
Heartburn
Hemochromatosis
Hemorrhoids
Hyperparathyroidism
Hypertension
Inflam. Bowel Dis.
Kidney Stone
Liver Cirrhosis
Migraines
Multiple Sclerosis
Obesity
Osteorithritis
Osteoporosis
Pancreatitis
Parkinson's Disease
Peyronies' Disease
Prolactinoma
Psoriasis
Sprain and Strain
Stroke
Ulcerative Colitis
Urin. Incontinence
Vitiligo
CONDITIONS
Acidosis
Acne
Acromegaly
Addison's Disease
Adrenal Crisis
Age. macular degn
Alzheimer's disease
Autoimmune
Hepatitis
Barrett's Esophagus
Cancer
Constipation
Colon Polyps
Crohns Disease
Cushing's Syndrm.
Diabetes
Erectile Dysfunction
Fecal Incontinence
Gallstones
Gastritis
Gastroenteritis
Gastroesophageal
Reflux (GERD)
Growth Hormone
Def.
Heartburn
Hemochromatosis
Hemorrhoids
Hyperparathyroidism
Hypertension
Inflam. Bowel Dis.
Kidney Stone
Liver Cirrhosis
Migraines
Multiple Sclerosis
Obesity
Osteorithritis
Osteoporosis
Pancreatitis
Parkinson's Disease
Peyronies' Disease
Prolactinoma
Psoriasis
Sprain and Strain
Stroke
Ulcerative Colitis
Urin. Incontinence
Vitiligo