GALLBLADDER CANCER
infertility.
If the underlying cause is a
pituitary tumour, there may be symp-
toms associated with the tumour, such
as headaches and visual disturbances.
Treatment
with
bromocriptine
sup-
presses prolactin production, but the
underlying cause of the disorder may
also require treatment.
galactosaemia
A rare, inherited condition in which the
body is unable to convert galactose (a
simple sugar that is derived from the
milk sugar
lactose)
into
glucose
(another
simple sugar) due to the absence of a
particular
enzyme
(a protein that acts as
a catalyst to speed up a reaction) in the
liver and in red blood cells.
Galactosaemia causes no symptoms at
birth, but
jaundice,
diarrhoea, and vom-
iting may develop after a few days, and
the baby fails to gain weight. If untreat-
ed, the disorder may result in liver
disease,
cataracts
(opacities in the lenses
of the eyes), and
learning difficulties.
The diagnosis is confirmed by urine
and blood tests. An affected person must
avoid milk products, and use lactose-
free milk, throughout life.
gallbladder
A small, muscular, pear-shaped sac, situ-
ated just beneath the
liver,
in which
bile
is stored and concentrated.
Bile, which is produced by the liver,
enters the gallbladder via the hepatic
and cystic ducts. When food passes
from the
stomach
into the
duodenum
(the first part of the small intestine),
gastrointestinal
hormones
make
the
gallbladder contract. This causes it to
release the bile, via the common bile
duct, into the duodenum, where it aids
the breakdown of fats contained in the
food. (See also
biliary system.)
gallbladder cancer
A rare cancer that occurs mainly in the
elderly. It is usually associated with
gall-
stones,
but affects only a tiny proportion
of those people with gallstones.
Gallbladder cancer may cause
jaundice
and tenderness in the abdomen, but it is
sometimes symptomless.
The cancer is usually diagnosed by
ultrasound scanning.
Treatment is by sur-
gical removal of the tumour, but if the
cancer has spread to the liver by the
time it is detected, the outlook is poor.
G
DISORDERS OFTHE GALLBLADDER
The gallbladder rarely causes problems
in childhood or early adulthood but,
from middle age onwards, an increasing
occurrence of
gallstones
may sometimes
give rise to symptoms.
The digestive system can function
normally without a gallbladder, and its
removal has few known long-term
adverse effects.
Metabolic disorders
The principal disorder, with which
most other gallbladder problems are
associated, is the formation of gallstones.
Every year thousands of people develop
gallstones.Women are affected up to
four times as often as men, depending
on their age and ethnicity.
The formation of gallstones results
from a metabolic problem in which the
chemical composition of bile (the
digestive juice stored in the gallbladder)
is altered.There are three main types of
gallstone: stones formed from the fatty
substance
cholesterol;
stones made from
bile
pigments; and mixed gallstones,
which contain both cholesterol and
pigments.The great majority are mixed.
Only about 20 per cent of affected people
experience symptoms or complications;
many carry “silent’’ gallstones, producing
no symptoms. Attempts by the gallbladder
to expel the stone or stones, however, can
cause severe
biliary colic
(abdominal pain).
Infection and inflammation
If a gallstone lodges in the gallbladder
outlet, trapped bile may irritate and inflame
the lining, and bile may become infected.
This disorder is called acute
cholecystitis
.
The first symptom may be biliary colic,
followed by fever and abdominal tenderness.
Repeated attacks of biliary colic and
acute cholecystitis can lead to chronic
cholecystitis, in which the gallbladder
becomes shrunken and thick-walled and
ceases to function. Rarely, it may become
inflamed when no gallstones are present:
a condition called acalculous cholecystitis.
Cholecystitis can proceed to
empyema,
in
which the gallbladder fills with pus; a high
fever and severe abdominal pain may result.
Congenital and genetic defects
Abnormalities that may be present from
birth include absence of the gallbladder, an
oversized gallbladder, or two
gallbladders.These defects, however,
rarely cause problems.
Tumours
Gallbladder cancer
usually occurs in a
gallbladder that contains gallstones.
This cancer is, however, extremely
uncommon compared to the high
prevalence of gallstones.
Other disorders
In rare cases where the gallbladder is
empty and a stone obstructs its outlet,
the gallbladder may become distended
and filled with mucus secreted by its
lining. A gallbladder with this problem
is known as a
mucocele.
INVESTIGATION
Gallbladder problems are investigated
by physical examination and imaging
techniques such as
ultrasound scanning,
radionuclide scanning,
or
cholecystography,
Blood tests may also be carried out.
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