Gall Stones Cholelithiasis Cholelithiasis Definition Most common biliary

Gall Stones Cholelithiasis

Cholelithiasis Definition • Most common biliary pathology Classification Gall stones are classified according to their chemical composition • Cholesterol stones • Pigment stones • Mixed stones • • • Cholesterol stones are usually solitary 90 % are mixed stones In mixed stones cholesterol is the major component Other components are calcium bilirubinate, calcium phosphate, calcium carbonate, calcium palmitate and proteins. Usually they are multiple; faceted Pigment stones are most common - bilirubinate. Small and multiple Some are hard some are only concretions of sludge rather than stones.

Incidence • Fat, fertile, flatulent female of fifty is the classical sufferer. • Both sexes • From childhood to the centenarian Aetiology Causal factors in gallstone formation • Metabolic • Infective • Bile stasis

Metabolic • Cholesterol, insoluble in water, is held in solution by a detergent action of bile salts and phospholipids with which it forms micelles. Excess of cholesterol relative to bile salts and phospholipids supersaturation lithogenic bile crystals form. • Bile cholesterol increases with age and is raised inwomen, partucularly those taking the contraceptive pill, in obsit and by clofibrate – a drug used in the treatment of certain hyperlipoproteinaemias. • Reduction of concentration of bile salts by oestrogens and ileal diseases which cause interruption in the intrahepatic circulation of bile salts

Infection • Often bile from patients with gallstones is steile • Bacteria may infect and may form the nidus for stone formation (Helicobacter pylori antigens found) Bile stasis • Decreased Contractility • Is reduced by oestrogens, in pregnancy and after truncal vagotomy situations in which the incidence of gall stones is increased. • Long term parenteral nutrition – lack of oral intake – reduced cholecystokinin – reduced contraction - stasis

• Pigment stones – haemolysis – bilirubin production is increased hereditary spherocytosis, sickle cell anaemia, thalassaemia, malaria and mechanical destruction of RBCs by prosthetic heart valves –benign and malignant bile duct strictures – ascaris lumbricoides, Escherichia coli infections Effects and complications of gallstones: In the gallbladder • Silent stones • Chronic cholecystitis • Acute cholecystitis • Gangrene • Perforation

• Empyema • Mucocele • Carcinoma In the bile duct • Obstructive jaundice • Cholangitis • Acute pancreatitis In the intestine • Acute intestinal obstruction (gallstone ileus)

Gall stone MRI Scan

• Gall stones are classified as mixed, pigment or cholesterol although all gall stones contain a variety of substances in differing proportions. Cholesterol stones tend to be large in size, often solitary and white in colour. Mixed stones are by far the most common and contain bilirubinates, phosphates, carbonates, calcium and other substances together with cholesterol. They are green, yellow, brown or black in colour, usually multiple and small in size. Pigment stones consist largely of calcium bilirubinate. They are prevalent in the far east and also occur in patients with accelerated red cell destruction such as in haemolytic anaemias and in patients with metal heart valves which cause red cell damage. Less than 10% of patients have sufficient calcium in their stones to appear on plain xray. Most gall stones form in the gall bladder where the bile is concentrated and stasis occurs. In 10 -15% of patients, stones migrate into the common bile duct where they may cause jaundice, cholangitis or pancreatitis. There have been reports of gall stones forming in the CBD in patients who have had their gall bladder removed although this is an uncommon event.

Multiple Gall Stones Calcified

Gallstones - MR

Intrahepatic Gallstone

Normal Gallbladder

Gallbladder Stones

Gall stones

Gallstones