It is the most common disorder of biliary tree. Overall prevalence of gall stone is 11%, 7% in men and 15% women. In people below 40 yrs sex ratio is 3:1. People with gall stone may be asymptomatic or present with recurrent upper abdominal pain. Some stones are detected on ultra sound scanning of abdomen.
Types of gall stone.
They are classified as cholesterol stones, pigment stones and mixed stones. Mixed stones are the most common types. Cholesterol stones are common in developed countries, whereas pigment stone occur in developing countries.
Different types of gall stone are pure cholesterol (white), mixed, bile salt predominant (black) stones. Cholesterol or cholesterol predominant (mixed) stones constitute 80% of gall stones. They are formed due to supersaturation of bile with cholesterol. Decreased gallbladder motility also aid the stone formation. Pigment stones occur following infection of biliary system, usually due to Escherichia coli and Klebsiella spp,
Risk factors associated with formation of cholesterol gall stones
Increased Cholesterol secretion seen in
* Age > 40 years
* Female sex (twice the risk in men)
* Genetic or ethnic variation highest Prevalence in North American Indians, Chilean Indians
* Pregnancy (risk increases with number of pregnancies
* High fat, low fibre diet
* Obesity
* Hyperlipidaemia
* Bile salt loss (ileal disease or resection)
* Diabetes mellitus
* Cystic fibrosis
* Antihyperlipidaemic drugs (clofibrate)
Impaired gallbladder emptying condition associated are
* Pregnancy
* Gallbladder stasis
* Prolonged Fasting
* Total parenteral nutrition
* Spinal cord injury
Pigment Stones cause are the following
* Demographic/genetic factors: Asia, rural setting
* Chronic hemolysis
* Alcoholic cirrhosis
* Pernicious anemia
* Cystic fibrosis
* Chronic biliary tract infection, parasite infections
* Increasing age
* Ileal disease, ileal resection or bypass
Factors that decreases gall stone formation.
* A low-carbohydrate diet
* Physical activity.
* Intake of caffeinated coffee help to reduce gall stone risk in women,
* High polyunsaturated and monounsaturated fats intake decreases the risk of gallstones in men.
