It is a large organ with many regulatory and storage functions. The liver
is situated in the upper abdomen, and weighs about 2 kg/4.5 lb. It is
divided into four lobes. The liver receives the products of digestion,
converts glucose to glycogen (a long-chain carbohydrate used for storage),
and breaks down fats. It removes excess amino acids from the blood, converting
them to urea, which is excreted by the kidneys. The liver also synthesises
vitamins, produces bile and blood-clotting factors, and removes damaged
red cells and toxins such as alcohol from the blood.
Weight about four pounds, the liver is the largest gland of the body
and the only organ that will regenerate itself when part of it damaged.
Up to 25 percent of the liver can be removed, and within a short period
of time, it will grow back to its original shape and size.
The liver has many functions, perhaps the most important of which is
its secretion of bile. This fluid is stored in the gallbladder for release
when needed for digestion. Bile is necessary for the digestion of fats;
it breaks fat down into small globules. Bile also assists in the absorption
of fat soluble vitamins A, D, F, and K, and helps to assimilate calcium.
In addition, bile converts beta-carotene to vitamin A. It promotes intestinal
peristalsis as well, which helps prevent constipation.
After food has been absorbed into the bloodstream through the intestinal
wall, it is transported by way of the hepatic portal system to the liver.
In the liver nutrients such as iron and vitamins A, B12 and D are extracted
from the bloodstream and stored for future use. These stored substances
are utilised for everyday activities and in times of physical stress.
In addition, the liver plays an important role in fat metabolism, in
the synthesis of fatty acids from amino acids and sugars, in the production
of lipoproteins, cholesterol, and phospholipids, and in the oxidation
of fat to produce energy. Finally, excess food in converted to fat in
the liver, which is then transported to the fatty tissues of the body
The liver also acts as a detoxifier. Protein metabolism and bacterial
fermentation of food in the intestines produces the by-product ammonia,
which is detoxified by the liver. The liver regulates protein metabolism.
In addition to detoxifying ammonia, the liver also combines toxic substances
including metabolic waste, insecticide residues, drugs, alcohol, and
chemicals with other substances the are less toxic. These substances
are then excreted from the kidneys. Thus in order to have proper liver
function, you must also have proper kidney function. Physicians have
found that when either the liver of kidney appears to be malfunctioning,
treating both organs produces the best health results.
In addition to its many other functions, the liver is responsible
for regulating blood sugar levels by converting thyroxine, a thyroid
hormone, into its more active form. Inadequate conversion by the liver
may lead to hypothyroidism. The liver creates GTF(Glucose tolerance
Factor) from chromium and glutathione. GTF is required for insulin
to regulate blood sugar levels properly. Excess sugar will be stored
in the body as glycogen, and then converted back to sugars when needed
for energy. The liver also breaks down hormones like adrenaline, aldosterone,
and estrogen, and insulin after they have performed their needed functions.
The liver weighs about 3 pounds and is the largest organ in the body.
It is located in the upper right side of the abdomen, below the ribs.
When chronic diseases cause the liver to become permanently injured
and scarred, the condition is called cirrhosis.
The scar tissue that forms in cirrhosis harms the structure of the
liver, blocking the flow of blood through the organ. The loss of normal
liver tissue slows the processing of nutrients, hormones, drugs, and
toxins by the liver. Also slowed is production of proteins and other
substances made by the liver.
Cirrhosis is the seventh leading cause of death by disease. About 25,000
people die from cirrhosis each year. There also is a great toll in terms
of human suffering, hospital costs, and the loss of work by people with
Cirrhosis has many causes. In the United States, chronic alcoholism
is the most common cause. Cirrhosis also may result from chronic viral
hepatitis (types B, C, and D).
Liver injury that results in cirrhosis also may be caused by a number
of inherited diseases such as cystic fibrosis, alpha-1 antitrypsin deficiency,
hemochromatosis, Wilson's disease, galactosemia, and glycogen storage
Two inherited disorders result in the abnormal storage of metals in
the liver leading to tissue damage and cirrhosis. People with Wilson's
disease store too much copper in their livers, brains, kidneys, and
in the corneas of their eyes.
In another disorder, known as hemochromatosis, too much iron is absorbed,
and the excess iron is deposited in the liver and in other organs, such
as the pancreas, skin, intestinal lining, heart, and endocrine glands.
If a person's bile duct becomes blocked, this also may cause cirrhosis.
The bile ducts carry bile formed in the liver to the intestines, where
the bile helps in the digestion of fat.
In babies, the most common cause of cirrhosis due to blocked bile ducts
is a disease called biliary atresia. In this case, the bile ducts are
absent or injured, causing the bile to back up in the liver.
These babies are jaundiced (their skin is yellowed) after their first
month in life. Sometimes they can be helped by surgery in which a new
duct is formed to allow bile to drain again from the liver.
In adults, the bile ducts may become inflamed, blocked, and scarred
due to another liver disease, primary biliary cirrhosis. Another type
of biliary cirrhosis also may occur after a patient has gallbladder
surgery in which the bile ducts are injured or tied off.
Other, less common, causes of cirrhosis are severe reactions to prescribed
drugs, prolonged exposure to environmental toxins, and repeated bouts
of heart failure with liver congestion.
People with cirrhosis often have few symptoms at first. The two major
problems that eventually cause symptoms are loss of functioning liver
cells and distortion of the liver caused by scarring. The person may
experience fatigue, weakness, and exhaustion. Loss of appetite is usual,
often with nausea and weight loss.
As liver function declines, less protein is made by the organ. For
example, less of the protein albumin is made, which results in water
accumulating in the legs (oedema) or abdomen (ascites). A decrease in
proteins needed for blood clotting makes it easy for the person to bruise
or to bleed.
In the later stages of cirrhosis, jaundice (yellow skin) may occur,
caused by the build-up of bile pigment that is passed by the liver into
Some people with cirrhosis experience intense itching due to bile products
that are deposited in the skin. Gallstones often form in persons with
cirrhosis because not enough bile reaches the gallbladder.
The liver of a person with cirrhosis also has trouble removing toxins,
which may build up in the blood. These toxins can dull mental function
and lead to personality changes and even coma (encephalopathy).
Early signs of toxin accumulation in the brain may include neglect
of personal appearance, unresponsiveness, forgetfulness, trouble concentrating,
or changes in sleeping habits.
Drugs taken usually are filtered out by the liver, and this cleansing
process also is slowed down by cirrhosis. The liver does not remove
the drugs from the blood at the usual rate, so the drugs act longer
than expected, building up in the body. People with cirrhosis often
are very sensitive to medications and their side effects.
A serious problem for people with cirrhosis is pressure on blood vessels
that flow through the liver. Normally, blood from the intestines and
spleen is pumped to the liver through the portal vein.
But in cirrhosis, this normal flow of blood is slowed, building pressure
in the portal vein (portal hypertension). This blocks the normal flow
of blood, causing the spleen to enlarge. So blood from the intestines
tries to find a way around the liver through new vessels.
Some of these new blood vessels become quite large and are called "varices."
These vessels may form in the stomach and oesophagus (the tube that
connects the mouth with the stomach). They have thin walls and carry
There is great danger that they may break, causing a serious bleeding
problem in the upper stomach or oesophagus. If this happens, the individual's
life is in danger, and action must be taken quickly to stop the bleeding.
The doctor often can diagnosis cirrhosis from the individual's symptoms
and from laboratory tests. During a physical exam, for instance, the
doctor could notice a change in how your liver feels or how large it
is. If the doctor suspects cirrhosis, he or she will recommend that
you have blood tests.
The purpose of these tests is to find out if liver disease is present.
In some cases, other tests that take pictures of the liver (such as
the computerised axial tomography scan, ultrasound, and the radioisotope
liver/spleen scan) may be recommended.
The doctor may suggest that the diagnosis be confirmed by putting a
needle through the skin (biopsy) to take a sample of tissue from the
In some cases, cirrhosis is diagnosed during surgery when the doctor
is able to see the entire liver. The liver also can be inspected through
a laparoscope, a viewing device that is inserted through a tiny incision
in the abdomen.
Treatment of cirrhosis is aimed at stopping or delaying its progress,
minimising the damage to liver cells, and reducing complications.
In alcoholic cirrhosis, for instance, the person must stop drinking
alcohol to halt progression of the disease. If a person has hepatitis,
the doctor may administer steroids or antiviral drugs to reduce liver
Medications may be recommended to control the symptoms of cirrhosis,
such as itching. Oedema and ascites (fluid retention) are treated by
reducing salt in the diet. Medications called "diuretics"
are sometimes used to remove excess fluid and to prevent oedema from
Diet and drug therapies can help to improve the altered mental function
that cirrhosis can cause. For instance, decreasing di-etary protein
results in less toxin formation in the digestive tract. Laxatives such
as lactulose may be given to help absorb toxins and speed their removal
from the intestines.
The two main problems in cirrhosis are liver failure, when liver cells
just stop working, and the bleeding caused by portal hypertension. The
doctor may prescribe blood pressure medication, such as a beta blocker,
to treat the portal hypertension.
If the individual bleeds from the varices of the stomach or oesophagus,
the doctor can inject these veins with a sclerosing agent administered
through a flexible tube (endoscope) that is inserted through the mouth
In critical cases, a liver transplant or another surgery (such as a
portacaval shunt) that is sometimes used to relieve the pressure in
the portal vein and varices may be an option.
Individuals with cirrhosis often live healthy lives for many years.
Even when complications develop, they usually can be treated. A few
individuals with cirrhosis have undergone successful liver transplantation.
It's important to remember, however, that all tests, procedures and
medications carry risks. To make an informed decision about your health,
be sure to ask your physician about the benefits, risks and costs of
all procedures and medications.