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Chapter 5: Disorders of the gallbladder 215

Rarely curative excision of a liver metastasis is per- hypercholesterolaemia has not been associated with

formed, particularly for slow-growing tumours. gallstones.
In most cases liver metastases indicate a poor prog- Increased concentration: Stone formation is more

nosis and treatment of the liver tumour will not be likely when the bile is concentrated, due to stasis, re-
curative. Patients should receive palliative care. duced gallbladder contractility or a reduced bile salt
pool.
Prognosis Precipitants: Gallstone formation may be around a
Depends on the primary tumour type. Obstructive jaun- focus or ‘nucleus’ such as bacteria, cells or other par-
dice is a poor prognostic factor. ticulate matter.
Reduced bile salt pool: Bile salts are normally recy-

cled by reabsorption at the terminal ileum through
Disorders of the gallbladder the enterohepatic circulation. Malabsorption (e.g. in
cystic fibrosis, Crohn’s disease or resection of the ter-
minal ileum) can lead to reduced amounts of bile and
Gallstone disease (cholelithiasis) predispose to nucleation.
Hormonal influences have been implicated: Preg-
Definition
Gallstones form from bile constituents in the gallbladder nancy, the oral contraceptive pill and hormone re-
and bile ducts. placement therapy all increase the incidence of stone
formation.
Pigment stones mainly consist of calcium bilirubinate.
Incidence/prevalence
Predisposing factors:
The most common disease affecting the biliary tract and
Increased production of bilirubin: Chronic haemo-
is increasing in frequency. It affects more than 20% of
lysis such as in congenital spherocytosis, haemo-
womenand8%ofmenintheUnitedKingdom,although
globinopathies and malaria leads to increased
>70% remain asymptomatic.
production of conjugated bilirubin.
Cirrhosis, biliary stasis and chronic biliary infections

Age
alsopredispose,althoughthemechanismisunknown.
Increases with age, most patients >40 years.
Bacterial action on bilirubin has been postulated.
Mixedstones are associated with anatomical abnormal-
Sex ities, stasis and previous surgery.
F > M (2:1)
Pathophysiology
Geography
Several different patterns of disease may result from gall-
More common in developed world.
stonesdependingonwherethegallstonesarelocated(see
Fig. 5.12).
Aetiology
Gallstones may be cholesterol stones (more common in
the developed world), pigment stones (more common Clinical features
in the Far East) or mixed stones. Gallstonesinthegallbladderareasymptomaticin90%
Cholesterol stones are predisposed to by supersatu- of cases.
ration of bile with cholesterol. Normally bile salts and Impaction of a gallstone in the outlet of the gallblad-
lecithin keep the cholesterol soluble, forming micelles. der or in the cystic duct produces biliary colic, a severe
Increased cholesterol: Obesity and rich, fatty diets colicky pain in the epigastrium and right hypochon-

can cause cholesterol-rich bile to be secreted. Con- drium, radiating to the back. Onset is often after a
versely, sudden weight reduction and cholesterol- meal or in the evening, the pain is variable in inten-
reducing diets may precipitate gallstones by mo- sity over several hours. Associated features are nausea,
bilising cholesterol stores from the liver. However, vomiting and retching. Jaundice may occur.