few and mild to severe with pain, fever,
Blood tests, including
may be used for diagnosis.
In most cases of acute viral hepatitis,
natural recovery occurs within a few
weeks. If the disorder is caused by expo-
sure to a chemical or drug, detoxification
may be possible.
may be required if the liver
is badly damaged. Rarely, a
is the only way of saving life. In all
cases, alcohol should be avoided.
Formerly known as serum
, this disorder is due to the hep-
atitis B virus, which is transmitted in
infected blood, blood products, or other
body fluids, often through contact with
needles, blood transfusions, or sexual
contact. After an incubation period of 1-6
months, the onset of symptoms, such as
headache, fever, and
, is sudden.
Most patients recover, but hepatitis B
can be fatal. A vaccine is available.
In about 5 percent of cases, the virus
continues to cause inflammation and can
still be detected in the blood
after infection. People who suffer from
persistent infection are at long-term risk
and may be
Caused by the hepatitis C
virus and formerly known as non-A non-B
, this infection is often trans-
mitted through sharing needles. Blood
transfusions no longer pose a signifi-
cant risk because of blood screening.
Hepatitis C has an incubation period
months and begins as a mild
illness which may go undetected. In
about 3 in 4 patients, chronic hepatitis
can progress to
of the liver and
an increased risk of
Inflammation of the
persisting for a prolonged period.
Eventually, scar tissue forms and liver
Chronic hepatitis may develop follow-
ing an attack of acute hepatitis (see
). It may also occur as the
result of an
, a viral
), a reaction
to certain types of drugs or, more rarely,
, such as
tiredness or no symptoms at all. It is
hepatitis is treated with
infections often respond to
In the drug-induced type, withdrawal of
the medication can lead to recovery. For
metabolic disturbances, treatment de-
pends on the underlying disorder.
An infection of the liver
caused by the hepatitis D virus, which
occurs only in people who already have
infection. People who develop
hepatitis D will usually suffer from
severe chronic liver disease.
A type of
by the hepatitis E virus, transmitted in
contaminated food or drink. The dis-
ease is similar to
Any type of
caused by a viral infection. Five viruses
that attack the liver as their primary tar-
get have been identified. They cause
A type of
Enlargement of the
occurring as a result of any liver disor-
liver, disorders of
Systems of medical
treatment in which various parts of
different plants are used to promote
health and to treat symptoms.
The transmission of traits and
disorders through genetic mechanisms.
Each individual inherits a combination of
via the sperm and egg cells from
which he or she is derived. The interac-
tion of the genes determines inherited
characteristics, including, in some cases,
disorders or susceptibility to disorders.
genetic disorders; inheritance.)
A measure of the extent to
which a disease or disorder is the result
of inherited factors, as opposed to envi-
ronmental influences such as diet and
climate. Certain disorders (such as
) are known to
be caused entirely by hereditary factors.
Others are caused by environmental
factors. Between these extremes are
many disorders (such as