-Gallstones are formed because of abnormal bile composition.
They are divided into two major types: cholesterol stones (>80% ) and pigment stones(<20%)
-Cholesterol gallstones usually contain >50% cholesterol monohydrate plus an admixture of calcium salts, bile pigments, and proteins.
Pigment stones are composed primarily of calcium bilirubinate;
-There are several important mechanisms in the formation of lithogenic (stone-forming) bile.
The most important is increased biliary secretion of cholesterol. This may occur in association with obesity, the metabolic syndrome, high-caloric and cholesterol-rich diets.
cholesterol gallstone disease occurs because of several defects, which include:-
(1) bile supersaturation with cholesterol,
(2) nucleation of cholesterol monohydrate with subsequent crystal retention and stone growth,
and (3) abnormal gallbladder motor function with delayed emptying and stasis.
Gallbladder hypomotility leading to stasis and formation of
a. Prolonged parenteral nutrition
d. Drugs such as octreotide
Excess Weight loss: Mobilization of tissue cholesterol leads to increased
biliary cholesterol secretion while enterohepatic circulation of bile
acids is decreased.
Pigment stones:- Black pigment stones are composed of either pure
calcium bilirubinate or polymer-like complexes with calcium and
Brown pigment stones are composed of calcium salts
of unconjugated bilirubin with varying amounts of cholesterol and
Symptoms of gallstone disease:-
Vary from asymptomatic to severe symptom.
Gallstones usually produce symptoms by causing inflammation or
obstruction following their migration into the cystic duct or CBD.
The most specific and characteristic symptom of gallstone disease
is biliary colic that is a constant and often long-lasting pain .
-Obstruction of the cystic duct or CBD by a stone produces
increased intraluminal pressure and distention of the viscus that
cannot be relieved by repetitive biliary contractions.
– The resultant visceral pain is characteristically a severe, steady ache or fullness in the epigastrium or right upper quadrant (RUQ) of the abdomen
with frequent radiation to the interscapular area, right scapula, or
Biliary colic begins quite suddenly and may persist with severe
intensity for 15 min to 5 h, subsiding gradually or rapidly.
Biliary colic may be precipitated by eating a fatty meal, by consumption of a large meal following a period of prolonged fasting, or by eating a normal meal; it is frequently nocturnal, occurring within a few hours of retiring.
Ultrasonography of the gallbladder is very accurate in the identification
The plain abdominal film may detect gallstones containing sufficient
calcium to be radiopaque.
Ursodeoxycholic acid (UDCA) decreases cholesterol saturation of bile and also appears to produce a lamellar liquid crystalline phase in bile that allows a dispersion of cholesterol from stones by physicalchemical
means. UDCA may also retard cholesterol crystal
In carefully selected patients with a functioning gallbladder and with radiolucent stones <10 mm in diameter,
complete dissolution can be achieved in ~50% of patients within
6 months to 2 years.