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he largest internal organ, the liver literally keeps you
alive. It performs over 100 separate bodily functions; and
its sheer complexity makes it susceptible to almost as many
different diseases. Fortunately, most are rare. But there are
a few that are all too common, including hepatitis,
cirrhosis, liver disorders in children, alcohol-related
disorders, and liver cancer.
The American Liver Foundation reports
that more than 25 million people are afflicted with liver and
gallbladder disease each year. Over 27,000 Americans die from
cirrhosis annually, making it the country's third leading
cause of death for people between the ages of 25 and 59, and
the seventh leading cause of death overall. Viruses,
hereditary defects, and reactions to drugs and chemicals are
among the known causes of liver breakdown. Though few
treatments are effective for life-threatening liver disease,
avoiding alcohol and other substances known to cause damage
can do a lot to safeguard this important organ. A recently
developed vaccine against the hepatitis B virus is now being
recommended for children and for adults such as health-care
workers who are in danger of exposure. (See section below on
viral hepatitis.)
The liver is located behind the lower
ribs, right below the diaphragm on the right side of the
abdomen. In an average-sized man, it is about the size of a
football, weighing a little over three
pounds.
A miniature refinery, the liver
processes many chemicals necessary for the body's overall
functioning. For example, it converts carbohydrates, fats,
and proteins into chemicals essential for life and growth. It
manufactures and exports to other organs some of the
substances they need to function properly, such as the bile
used by the intestines during digestion. It modifies drugs
taken to treat disease so that they can be used more easily
by the body. And it cleanses the blood of toxic substances
either ingested or produced by the body
itself.
But that's only part of the picture.
Below are some of the liver's many other important
functions:
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Regulates the blood's ability to
clot--governs the transport of fat
stores
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Stores extra vitamins, minerals, and
sugars to prevent shortages
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Produces quick energy as
needed
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Controls the production and
excretion of cholesterol
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Breaks down
alcohol
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Monitors and maintains the right
level of numerous chemicals and drugs in the
blood
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Maintains and controls hormone
balance
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Helps the body resist infection by
producing immune factors and cleansing bacteria from the
blood
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Stores iron
The Threat of Viral
Hepatitis
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Viral hepatitis, a contagious infection
of the liver, afflicts more than 70,000 Americans each year.
It is usually caused by one of three different
organisms.
Hepatitis A , formerly known as infectious hepatitis,
can be contracted by consuming contaminated water or food,
most notably shellfish. Since the virus is eliminated in the
stool, it also spreads through improper hand washing,
especially by restaurant workers or anyone else who handles
food. Although hepatitis A is seldom serious, in one percent
of the cases it can cause severe liver failure and death. It
does not cause chronic hepatitis and will not lead to
cirrhosis or other long-term liver
problems.
Hepatitis B , formerly known as serum hepatitis, is
found in blood and other body fluids such as urine, tears,
semen, breast milk, and vaginal secretions. It is usually
transmitted in blood, via transfusions, or through illicit
injectable-drug use. But it also can be contracted through a
minor cut or abrasion, or during such everyday acts as
toothbrushing, kissing, or having sex. Infants can contract
the disease from the mother at birth, or from the mother's
breast milk. Dental work, ear piercing, and tattooing are
other ways people can get hepatitis
B.
Type C hepatitis virus is the cause of a disease known
as "non-A, non-B hepatitis," which is also contracted through
contact with contaminated blood, or through household or
sexual contact with an infected person. It affects
approximately 170,000 Americans each
year.
Viral hepatitis may produce no symptoms
at all. When they occur in type A, they usually begin
suddenly and last for several weeks. This period is followed
by a convalescent phase of anywhere from two to 12 weeks.
Symptoms of viral hepatitis mimic the flu and include mild
fever, fatigue, nausea, muscle and joint aches, loss of
appetite, vomiting, occasional diarrhea, and vague abdominal
pain. Some people also develop a yellow cast to the skin and
whites of the eyes known as jaundice, along with dark-colored
urine, clay-colored stools, and itching of the skin. The
liver may be enlarged and tender.
Patients usually recover completely from
hepatitis A and develop a lifelong immunity to it. Immune
globulin (IG) should be administered to anyone exposed to
type A hepatitis as soon as possible or within two weeks
after jaundice appears. This medication is 80 to 90 percent
effective in preventing the disease. A vaccine for hepatitis
A is now available.
Hepatitis B also frequently has no
symptoms; but if they do occur, they are similar to those of
hepatitis A. The disease follows an unpredictable course,
sometimes incapacitating a person for weeks or months and
leading to complications, but usually ending in full
recovery. Hepatitis C is similar to hepatitis B, but milder.
However, like hepatitis B, it may develop into a chronic form
in approximately 30 to 50 percent of those who contract
it.
The problem with hepatitis B is that
five to 10 percent of those who become infected with this
disease become chronic carriers who can spread it to others
for an indefinite period of time. At present there are more
than a million of these silent carriers in this country, and
their number is growing by two to three percent annually.
Consequently, authorities recommend that all children and
anyone with a high risk of exposure be vaccinated against
this dangerous virus.
Chronic carriers usually do not develop
chronic hepatitis. If it does develop, however, cirrhosis and
primary cancer of the liver can be long-term consequences. An
estimated 4,000 people in the United States die from
hepatitis B-related cirrhosis annually. Carriers are many
times more likely to get liver cancer than are
non-carriers.
Treatment for acute hepatitis consists
of rest and small, nourishing meals; fluids; and sometimes
anti-nausea drugs such as trimethobenzamide (Tigan). Chronic
cases of hepatitis B and C are now being treated with
interferon, a biotech medicine derived from the human immune
system.
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THE GALLBLADDER
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The gallbladder stores bile, a
substance the liver produces to aid digestion. The most
common disorder of the gallbladder is the formation of
gallstones. These stones often get stuck in the bile
ducts that lead from the gallbladder to the first part
of the small intestine, causing the gallbladder to
become inflamed. Gallbladder surgery, in which the
entire organ is removed, is one of the most common
operations in this country. Laparoscopic
cholecystectomy, a new procedure that requires only a
small incision, has cut down stress and recovery time
dramatically. Chenodiol, a recently available drug that
dissolves gallstones, is an alternative to surgery.
However, due to limited success and troublesome side
effects, it is not widely used.
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Other Diseases of the
Liver
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In cirrhosis, liver cells are damaged
and replaced by scar tissue which, as it accumulates, hardens
the liver, diminishes blood flow, and causes even more cells
to die. The loss of liver function that accompanies this
degenerative condition results in gastrointestinal
disturbances, jaundice, enlargement of the liver and spleen,
emaciation, and accumulation of fluid in the abdomen and
other tissues. Over half of the deaths related to cirrhosis
are due to alcohol abuse, hepatitis, and other viruses.
Chemicals, poisons, too much iron or copper, and blockages of
the bile duct also may cause the
disease.
Treatment of cirrhosis usually consists
of eliminating the underlying cause, if possible, to avoid
further damage, and preventing or treating complications.
Care is mostly supportive, often including a specialized
diet, diuretics (water pills), vitamins, and abstinence from
alcohol. For some patients, a liver transplant is now a
feasible option.
Liver abscesses are caused by bacteria, such as
Escherichia coli (
E. coli ) or staphylococcus (staph), or by
Entamoeba histolytica, the parasite that causes amebic
dysentery. In either case, the offending organisms destroy
liver tissue, leaving a cavity that fills with other
infectious organisms, white blood cells, and liquefied liver
cells. Common symptoms include shoulder and abdominal pain,
fever, weight loss, chills, nausea, vomiting, anemia, and, if
there is severe liver damage, jaundice. If the offending
organism can't be determined, liver abscesses are treated
with long-term antibiotics such as aminoglycosides,
cephalosporins, clindamycin, or chloramphenicol. If
E. coli is causing the infection, treatment includes
ampicillin; for
Entamoeba histolytica , chloroquine (Aralen), or
metronidazole (Flagyl) are included.
Pediatric liver diseases afflict tens of thousands of
children in this country annually, and kill hundreds each
year. More than 100 different liver diseases are found in
infants and children. Most of these disorders are genetic.
Among the more common are:
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Biliary atresia, an inadequate bile
duct, often fatal but sometimes relieved by
surgery;
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Chronic active hepatitis, in which
scar tissue forms and destroys the
liver;
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Wilson's disease, in which an
abnormally large buildup of copper in the liver is
treated with vitamin B6 and d-penicillamine, or, in some
cases, corticosteroids such as
prednisone;
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Reye's syndrome, an acute, often
fatal disease secondary to flu or other infections in
which fat accumulates in the liver and the patient lapses
into coma.
Other serious diseases of the liver,
fortunately seen less frequently than these discussed above,
include fatty liver, hepatic coma, and liver
cancer.
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