Liver 3 + SG

what is the job of the biliary system

• store, concentrate and deliver bile to the intestines

• retrieve bile salts from the terminal ileum and send back to the liver

what are the 4 components of the biliary tract

• hepatocytes and canaliculus

• ductules and ducts

• gallbladder

• sphincter of oddi

func of hepatocyte and canaliculus in the biliary tract

bile will be made in hepatocytes → dumped in canaliculi

funx of ductules and ducts in the biliary tract

modification of bile

funx of gallbladder in the biliary tract

storage and concentration of bile

funx of the sphincter of Oddi in the biliary tract

regulated delivery into the duodenum

what is in bile

mainly: water and bile salts, other: bilirubin, cholesterol, phospholipids, drug metabolites, xenobiotics, vitamins, electrolytes, heavy metals, IgA, environmental toxins

what type of molecules exist inside vs outside of a micelle

• inside: hydrophobic

• outside: hydrophilic

what is the purpose of a micelle

• will transport lipids through water environments

• aggregation of micelles will dec osmolarity of bile salts

what is the effect of CCK on the gallbladder

will cause contraction of the gallbladder and will release bile to go into the duodenum

what are the 3 types of gallstones

• cholesterol

• mixed

• black pigments

what are cholesterol gallstones made out of

primarily cholesterol

what are mixed gallstones made out of

mix of cholesterol and bilirubinate

what are black pigments made up of

• calcium bilirubinate (Ca + unconjugated bilirubin)

• will come from unconjugated bilirubin in the bile duct → form black stones

most gallstones are what type

mixed

what are the 3 things required for a stone to form

• thermodynamics → solubility

• residence time → stasis time

• kinetics → nucleation and crystal growth

what role does bacteria play in forming a gallstone

most gallstones will either from around mucous in the gallbladder or bacteria

what has to happen for a gallstone to become symptomatic

• needs to actually block something

• can hang out for forever if not blocking anything and you wouldn’t feel a thing

what are the risk factors for gallstone formation (8)

• obesity

• rapid weight loss

• TPN

• pregnancy

• oral contraceptives

• ileal disease

• diabetes mellitus

• hemolytic anemia

why is this a risk factor for gallstone formation: obesity

cholesterol supersaturation of bile

why is this a risk factor for gallstone formation: rapid weight loss

bariatric surgery: reduced bile acid synthesis bc you’re not usually eating fats, impaired gallbladder mobility due to dec CCK stimulation → allows bile to crystalize in gallbladder longer

why is this a risk factor for gallstone formation: TPN

• lack of enteral stimulation of CCK

• when feeding someone IV → will NOT stimulate CCK this way

why is this a risk factor for gallstone formation: pregnancy

estrogen → supersaturation of bile w cholesterol, dec gallbladder motility-progesterone

why is this a risk factor for gallstone formation: oral contraceptives

inc cholesterol secretion in bile

why is this a risk factor for gallstone formation: ileal disease

dec bile salt concentration in bile → bc not absorbing bile salts in ileum → deficient in bile salts

why is this a risk factor for gallstone formation: diabetes mellitus

gallbladder hypomotility

why is this a risk factor for gallstone formation: hemolytic anemia

black stones → have excess calcium bilirubinate

what is cholelithiasis, does jaundice present

• gallstones in the gallbladder

• no inflammation or blockage → no jaundice

what is choledocholithiasis, does jaundice present

• gallstones in the common bile duct or cystic duct

• doesn’t mean there is obstruction of there is inflammation

  • no jaundice

what is cholecystitis, does jaundice present

• gallstone obstruction in the gallbladder

• there will be inflammation

  • will see jaundice

what is cholangitis

• inflammation of the bile duct often due to choledocholithiasis

  • or any other gallstone obstruction

• there is inflammation

  • jaundice will be present

what is gallstone ileus

gallstones will erode through bladder wall, enter small bowel lumen and obstruct at ileocecal valve

what is chronic cholecystitis

multiple episodes of inflammation from gallstone obstruction that will cause gallbladder thickening and contraction w variable wall thickness and appearance

what is porcelain gallbladder

from long standing inflammation → will become fibrotic and calcified

what is ascending cholangitis

infection of the biliary tree

what can cause ascending cholangitis

mostly by obstruction → will lead to bacterial overgrowth from duodenum

what is the charcot triad

associated w ascending cholangitis:

• jaundice

• fever

• RUQ pain

what is primary sclerosing cholangitis

an autoimmune mediated disease often associated w idiopathic inflammatory bowel disease, often ulcerative colitis

what is the proposed theory of primary sclerosing cholangitis

t cells activated by damaged mucosa in ulcerative colitis recognized a cross-reacting bile duct antigen → maybe triggered by infection of intestinal microbiota

what type of cancer is the pt at risk for in primary sclerosing cholangitis

cholangiocarcinoma

what is primary biliary cholangitis

autoimmune disease resulting from T cells attacking autoantigens on small bile interlobar ducts

what population does primary biliary cholangitis occur in

middle-aged females

what population does sclerosing biliary cholangitis occur in

young/middle-aged males

what blood test is elevated in primary biliary cholangitis vs primary sclerosing cholangitis

• PBC: will have a positive anti-mitochondrial antibodies and elevated alkaline phosphatase

• PSC: maybe elevated ANCA

radiology in primary biliary cholangitis vs primary sclerosing cholangitis

• PBC: normal

• PSC: strictures and beading of large bile ducts, pruning of smaller ducts

duct lesion in primary biliary cholangitis vs primary sclerosing cholangitis

• PBC: florid duct lesion and loss of small ducts only

• PSC: inflammatory destruction of extrahepatic and large intrahepatic ducts, fibrotic obliteration of medium and small intrahepatic ducts

what is secondary biliary cholangitis

inflammation and destruction of the intrahepatic bile ducts due to a prolonged obstruction of the extrahepatic biliary tree

etiology of secondary biliary cholangitis

extrahepatic biliary obstruction usually by gallstones or cancer → inc intrahepatic biliary pressure → injury/inflammation/fibrosis → biliary stasis

what is cholangiocarcinoma

malignant transformation of cholangiocytes

risk factors of cholangiocarcinoma

• previous exposure to thorotrast

• infection by liver flukes

• primary sclerosing cholangitis

• cirrhosis

what is the tx recommended for symptomatic obstruction by gallstones

cholecystectomy → removal of gallbladder

what is usually the first episode seen in symptoms that develop from gallstone obstruction

biliary colic

what is biliary colic

severe, fluctuating pain in the gut area