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Hemochromatosis -- the Celtic curse
By John Messmer
Penn State Family and Community Medicine
Penn State Milton S. Hershey Medical Center
Penn State College of Medicine
March brings St. Patrick's Day, the traditional day to celebrate all things
Irish. The 2000 census shows more than 10 percent of the U.S. population
reporting Irish ancestry. In Pennsylvania, it's more than 16 percent. Many
things are associated with Irish-Americans -- woolen goods, Celtic music, and
Irish foods and drinks, but few people know the story of Celtic curse.
The Celtic curse refers to the disease of hereditary hemochromatosis, or HH. It
is so-called because it is common in people of Celtic background: Irish, Scots,
Welsh and British. Additionally, HH is one of the most common genetic diseases
in the United States, occurring in one in 200 Caucasians with one in 10 being a
carrier -- most, but not all of these having Celtic ancestry. By contrast,
sickle cell anemia occurs in one in 500 African-Americans with one in 12 being
carriers. Despite its prevalence, it remains relatively unknown, even among
physicians.
HH causes iron to be absorbed even when it is not needed. Normally, people
absorb a tiny amount of iron daily, just enough to replace what is lost from
normal bodily functions. Women absorb more during their childbearing years to
replace iron loss from menstrual blood. In hemochromatosis, iron continues to
be absorbed excessively. Once the places where iron is normally stored are
full, iron begins to be stored in the liver, heart, skin and other organs,
damaging them. This can lead to heart failure and rhythm disorders, diabetes,
cirrhosis and liver tumors. Untreated, it can be fatal.
HH is the result of genetic mutations, the most common ones called C282Y and
H63D. The mutation is believed to have developed about 40,000 years ago in what
is now Ireland to compensate for an iron-poor diet. At that time, it would have
been beneficial.
The mutations are passed on from parents to children. The HH genes are
recessive. That means the disease occurs only when two copies of the gene are
present -- one from each parent. If only one copy is passed, the person is a
carrier. The full-fledged disease is seen only in those with two copies.
Carriers also can store too much iron, but they rarely have organ damage.
In the most common form of HH, males usually do not develop symptoms until after
age 30, and women may not show problems until after menopause because they lose
iron regularly during menses. Symptoms relate to the organs that become
overloaded with iron and can include arthritis, liver disease, diabetes,
thyroid deficiency, bronze skin color, impotence and adrenal gland
abnormalities and such nonspecific symptoms as fatigue or aches.
The problem is actually easy to diagnose before any damage occurs by measuring
iron levels in the blood. This is a different test than a blood count, the
typical test for anemia. Having a normal blood count does not give any
information about HH. Blood donor centers test for too little iron; passing the
test does not say anything about having too much iron.
Screening for HH is done with a serum iron level and transferrin saturation and
often a ferritin level. Transferrin is a protein that carries iron in the blood
and ferritin is an iron storage protein. If the iron level is high and
transferrin is more than 40 percent saturated or ferritin is higher than 200 or
so, HH should be considered. If a doctor tells a patient that his or her iron
is great or high enough that there is no need to worry about anemia, the
patient should ask how high it is and whether he or she should be tested for
hemochromatosis.
To diagnose HH, a blood sample is tested for the two more common DNA mutations.
Until the DNA test was available, liver biopsy was needed to test for iron
deposits. Biopsy is reserved for those who have developed cirrhosis of the
liver to help determine if the cause is hemochromatosis.
People with one copy of the gene should avoid taking extra iron in vitamins and
supplements and should avoid using iron cookware and extra vitamin C, which
enhances iron absorption. A person with two copies of the gene has the disease
and should begin a program of iron elimination. Treatment is through
therapeutic phlebotomy. This is just like the process of donating blood -- a
unit is removed as often as weekly if needed to reduce iron levels to normal.
Treatment can be ordered by many types of medical specialists including a
family physician.
The family of anyone with even one HH gene should consider testing even if they
have no symptoms. Those with the disease will pass on one copy of the gene to
each of their children. Carriers have a 50/50 chance of passing on a
hemochromatosis gene to each child. Some advocate testing in childhood if one
or both parents are known to carry the gene so the child's diet can be managed
to keep iron levels under control.
Hereditary hemochromatosis is a fairly common disorder, but it's the luck o' the
Irish to be able to diagnose and treat it effectively, especially if found
early. This St. Patrick's Day, when a bit of the blarney leads to tales of
leprechauns and shamrocks, remember the story of the Celtic curse.
Coeliac disease -- another Celtic curse?
Difficult path to coeliac diagnosis
By Angela Long
One in every hundred Irish people suffers from coeliac disease. Yet it
can take months, if not years, to have it identified and treated correctly.
The question often arises whether there are more people with food allergies
these days, or is it just that there is more recognition of conditions that
used to be ignored or labelled incorrectly.
People who cannot tolerate wheat, barley, oats or rye – coeliacs – have
been around in Ireland for a long time. Their numbers appear to have swelled in
recent years, but that could be just a case of better diagnosis now, although,
as the Coeliac Society of Ireland says, there is a lot still to be done in
raising awareness.
Ireland in fact has one of the highest incidences of coeliac condition in the
world, particularly in the south-east. Genes are believed to be responsible.
Globally, around one in every 250 people is believed to have the coeliac gene.
Coeliac disease is a lifelong condition of the small intestine (bowel). What
coeliac individuals cannot take is gluten, a mixture of two proteins called
gliadin and glutenin. This is found in wheat, barley and rye. Oats is not in
itself a cause, but people with coeliac disease are often told to avoid them
because of the possibility of contamination with other gluten-containing
grains.
In coeliac disease, gluten causes the immune system to produce antibodies that
attack the delicate lining of the bowel, which is responsible for absorbing
nutrients and vitamins from food.
Coeliac disease can be diagnosed at any age, but it is often found in babies
after weaning, when cereals are first introduced into the diet. Diagnosis can
be slow as doctors will try for more obvious diseases. A survey this year of
coeliacs in Britain found that the average time before a correct diagnosis was
13 years.
The symptoms, such as upset stomach, diarrhoea, can be inconclusive. A blood
test can give a good indication of whether a person has the condition, but
sometimes an endoscopy is required.
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