BILIARY AND PANCREATIC PATHOLOGY Flashcards
what is in bile?
bile salts, bilirubin phospholipid, cholesterol, amino acids, steroids, enzymes, porphyrins, vitamins, and heavy metals, as well as exogenous drugs, xenobiotics and environmental toxins
what are the functions of bile?
helps break down fats by emulsification
helps elimate waste products e.g. bilirubin and excess cholesterol
contains some signalling molecules
what breaks down cholesterol and what does it break down into?
7 alpha hydroxylase breaks it down into 2 primary bile acids - cholic acid and chenodeoxycholic acid
(hepatocytes)
where do the primary bile acids get broken down and into what?
in the intestines they get de-hydroxylated into 2 secondary bile acids deoxycholic acid and lithocholic acid
what gives rise to bile salts?
primary and secondary bile acids are conjugated by the liver with glycine and taurine
what are some pre-hepatic causes of jaundice?
Gilbert disease haemolytic anaemias drugs resorption from a bleed ineffective erythropoeisis
what is gilberts disease?
It is an inherited metabolic disorder that causes excess unconjugated bilirubin due to defective conjugating enzymes in the hepatocytes. 3% of the population have it
what are some hepatic causes of jaundice?
hepatitis drugs toxins cancer primary sclerosing cholangitis alcohol non-alcoholic fatty liver disease
what are some post-hepatic causes of jaundice?
gallstones pancreatic cancer CCA strictures biliary atresia primary sclerosing cholangitis
what is primary sclerosing cholangitis?
inflammation causes scars within the bile ducts
what are some gallbladder pathologies?
cholecystoses stones cholecystitis carcinoma congenital anomalies
what are cholecystoses?
conditions characterised by the accumulation of cholesterol and other fats in the gallbladder
what are the 2 main types of cholecystoses?
cholesterolosis
adenomyomatosis
what are some risk factors of gallstones?
rapid weight loss obesity being female being >40 being pregnant not moving/stasis
why are women more at risk than men of gallstones?
oestrigen increases cholesterol stone formation
why is obesity associated with increased gallstone risk?
obesity is linked to increased levels of cholesterol
why is rapid weight loss a risk factor for gallstones?
asthebody starts to metabolize fats so more cholesterol is released
what are most gallstones composed of?
80% cholesterol
rest are bilirubin
what are the 3 general reasons for gallstones?
bile contains too much cholesterol, too much bilirubin or not enough bile salts
outline the pathology of cholesterol stones?
bile becomes supersaturated with cholesterol/not enough bile salts/gallbladder stasis
= cholesterol precipitates out of bile and forms solid stones
outline the pathology of bilirubin stones?
too much bilirubin in bile = combines with Ca2+ to form calcium bilirubinate which is a solid precipitate
what are brown pigmented gallstones usually caused by?
gallbladder/biliary tract infection