Cholelithiasis

DEFINITION

The presence of calculi (gallstone) in the gallbladder. The medical term for gall stones is cholelithiasis. Chole is from the Greek meaning "bile". Lithos is "stone" and iasis is "condition of".

ETIOLOGY

Gallstones are crystalline structure formed by concretion (hardening) and accretion (adherence of particle, accumulation) of normal or abnormal bile constituents. According to various theories, there are four possible explanations for stone formation.

First, bile may undergo a change in composition. Studies of subject with cholesterol gallstone will indicate that their bile is supersaturated with cholesterol but deficient in bile salts. The cholesterol saturation of bile seems to increase with age. Changes in bile composition however do not completely explain hoe gallstones formed.

Second, gall bladder stasis may lead to bile stasis. Bile stasis may (1) change the composition of bile, (2)s supersaturated bile with cholesterol, and (3) precipitate some bile constituents. Gallbladder stasis may result from decreased contractility and emptying of gallbladder spasm of the sphincter of Oddi. Circumstances in which bladder stasis occur are associated with a high rate of gallstone formation. Most specifically, TPN without oral intake for longer than one month is associated with gallbladder sludge formation and cholelithiasis. Delayed emptying of gallbladder may correlate with hormonal factors. In pregnant women, the female sex hormone estrogens increases, which increases dietary uptakes of cholesterol and biliary cholesterol secretion. This may explain why gallstone seems to be associated with pregnancy. In addition, one of the precautions for administering estrogen balances to postmenopausal women is gallbladder disease.

Third, infection may predispose a person to stone formation. Inflammatory debris can form a nidus (point of origin) for stone growth. The related tissue injury may alter the composition of bile increasing the reabsorption of bile salts and lecithin. Certain organisms may also play a part in stone formation by altering the composition of bile. For example, Escherichia coli increases the amount of bilirubin available for pigment stones and Streptococcus faecalis reduces the bile salts.

Fourth, genetic and demography can affect stone formation, as shown in higher prevalence in Pima and Chippewa Native Americans, Northern Europeans, and South Americans than in Asians.

RISK FACTORS

• Overweight
• Rapid weight loss
• Estrogen intake and birth control pills(estrogen increases the concentration of cholesterol in the bile)
• Diabetes
• Over age 40 and increase in risk as one ages
• Female especially those who have had children
• Ethnicity (Pima Indians and Mexican-Americans)
• High triglycerides, high LDL cholesterol, decreased HDL cholesterol,
• Alcohol intake
• Family history of gallbladder disease (Heredity)
• Cholesterol-lowering drugs, immunosuppressive drugs and others
• Very Low Calorie Diets
• Diet high in saturated fats
• Diet high in refined foods and sugars
• Diet low in fiber (which is what the refined diets are) and not enough vegetables
• Non-fat diets
• Low-fat diets
• Constipation

Diseases such as chronic inflammatory bowel disease, chrons disease (ulcerative colitis is contraversial) Hemolytic anemias.