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INTRODUCTION

Bile is a yellow-green fluid that is made by the liver, stored in the

gallbladder and passes through the common bile duct into the duodenum

where it helps digest fat. The principal components of bile are cholesterol,

bile salts, and the pigment bilirubin.

The liver secretes about 700 ml of bile each day. Bile contains no digestive

enzymes, but it plays an important role in digestion by diluting and

neutralizing stomach acid and by dramatically increasing the efficiency of

fat digestion and absorption. Digestive enzyme cannot act efficiently on

large fat globules. Bile salts emulsify fats, breaking the fat globules into

smaller droplets, much like the action of detergents in dishwater. The small

droplets are more easily digested by digestive enzyme. Bile also contains

excretory products such as bile pigments, cholesterol and fats. Bilirubin is abile pigment that results from the breakdown of hemoglobin.

I- Physical Properties of Bile

1.Yellow-green fluid- bile receives its color from the presence of thebile pigments such as bilirubin.

Bile pigments a group of substance that contributes to the color of

bile, which may range from a yellowish to brown.

2. Bitter in taste

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II- Chemical Composition of the Bile

Bile is a yellowish green viscous liquid with a pH of 7.8 to 8.6.Because it is

alkaline, it serves to neutralize the acid entering from the stomach.

Primarily, bile contains bile salts, bile pigment, and cholesterol.

Biliary sludge is most commonly composed of cholesterol monohydrate

crystals, calcium bilirubinate granules, or other calcium salts embedded in

strands of gallbladder mucus. Proteins and xenobiotics, such as

ceftriaxone, are also important components. Sludge contains a large

proportion of undefined residue, protein-lipid complexes, and mucin.

Calcium bilirubinate granules are almost invariably present, and bilirubinis usually found in its unconjugated, least soluble form. The source of the

unconjugated bilirubin is controversial. Bilirubin is excreted by the liver

mainly in its diglucuronide form, but small amounts of the

monoglucuronide and unconjugated forms are also seen. The enzyme -

glucuronidase, which deconjugates bilirubin, may be important. Conditions,

in which the activity of this enzyme is increased, such as chronic low-grade

biliary infection, are associated with pigment gallstones. -glucuronidase

has also been identified in uninfected bile, probably having originated in the

biliary epithelium. Nonenzymatic hydrolysis of bilirubin may occur. Thechemical composition of sludge varies with the clinical situation. In the

general population, sludge is composed of calcium bilirubinate and

cholesterol monohydrate crystals in various proportions. In patients

receiving total parenteral nutrition, sludge consists primarily of calcium

bilirubinate; in pregnant women, cholesterol monohydrate predominates. In

patients receiving high-dose ceftriaxone therapy, sludge is composed of

calcium-ceftriaxone complexes.