Flashcards in Pathology of the biliary tract and pancreas Deck (40):
What liver function test results are usual for post hepatic obstruction?
Raised alkaline phosphatase
only modest elevation of transferases
What are important causes of occlusion of the bile duct?
Strictures e.g. following previous biliary surgery
Tumours- carcinoma of the extrahepatic bile duct or head of the pancreas
What causes gallstones?
Calculi migrating from the gall bladder to obstruct the common bile duct
What is cholangitis?
When bile stasis above the obstruction in the bile duct predisposes to infection of the biliary tract and the ducts become inflamed, and the patient develops a fever.
What is ascending cholangitis?
The propagation of biliary infection proximally into the intrahepatic ducts, which can lead to the formation of liver abscesses.
Why are dilated intrahepatic ducts detected by ultrasound scan a contraindication to diagnostic liver biopsy in the jaundiced patient?
A risk of biliary leakage
What is cholelithiasis?
Gallstone formation within the biliary system
What are risk factors for cholesterol rich stones?
Female gender and obestiy
(Fat, fair, forty, fertile, female)
What can gallstones consist of?
Pure cholesterol- yellow, opalescent
Bile pigment- small black
Why do gallstones form?
When there is an imbalance of the constituents of bile, which results in precipitation.
What are the pathological effects of gallstones?
Inflammation of the gall bladder (cholecystitis) and its complications
Predisposition to carcinoma of the gall bladder
Obstruction of the biliary system, resulting in biliary colic and jaundice
Infection of static bile, causing cholangitis and liver absecesses
Gallstone ileus due to intestinal obstruction by a gallstone that has entered the gut through fistulous connection iwth the gall bladder
What is the pathogenesis of pigment stones?
Excess bilirubin which cannot be solubilised in bile salts
Could be due to excess haemolysis e.g. haemolytic anaemia
What may be contributory factors to gallstone pathogenesis?
Gallbladder pH and mucosal glycoproteins
How can gallstones trigger pancreatitis?
By damaging the sphincter off odd which can allow a reflux of duodenal contents up into the pancreas
What is cholecystitis?
What is it almost always associated with?
Inflammation of the gallbladder
Can be acute or chronic
What does acute cholecystitis cause?
It can cause empyema, rupture and peritonitis
causes intense adhesions in 2-3 days
What is chronic cholecystitis?
Associated with Gallstones
May develop insidiously or after bouts of acute cholecystitis
Galbladder wall is thickened but not distended (Cardinal feature)
What is carcinoma of the gallbladder?
Associated with gallstones
Local invasion of liver
What is cholangiocarcinoma associated with?
Ulcerative Colitis and Primary Sclerosing Cholangitis
How does a patient with cholangiocarcinoma present?
with obstructive jaundice
What type of cancer is cholangiocarcinoma?
What is pancreatitis?
Inflammation of the pancreas- may be acute or chronic
Overlap exists between acute and chronic
Is severe acute pancreatitis a medical emergency?
How does severe acute pancreatitis present?
Sudden onset of severe abdominal pain often radiating to the back
Patient may go into shock with renal and respiratory failure
What is biochemical marker associated with severe acute pancreatitis?
Raised serum amylase
What are most cases of acute pancreatitis related to?
Alcohol or gallstones
What are other causes of acute pancreatitis?
Vascular insufficiency (e.g. shock)
certain infections, e.g. mumps
iatrogenic factors e.g. after ERCP or an operation
What is the pathogenesis of acute pancreatitis?
Bile reflux, duct obstruction due to stone and damage to sphincter of Oddi all cause pancreatic duct epithelial injury
Loss of protective barrier allows autodigestion of pancreatic acini
Release of lytic pancreatic enzymes proteases and lipases
Intra- and peripancreatic fat necrosis (lipases)
Tissue destruction and haemorrhage (proteases)
What is a cardinal histological sign of pancreatitis?
What is Grey turner's sign?
What causes it?
Skin discolouration on the flanks
The lipolytic enzymes cause fat necrosis which can be extensive if it involves the anterior abdominal wall it can cause skin discolouration.
What are complications of acute pancreatitis?
What are pseudocysts?
Cysts without epithelial lining
What happens in chronic pancreatitis?
There is continuing inflammatory process with exocrine atrophy and replacement of pancreatic tissue with fibrosis
What is the commonest cause of chronic pancreatitis?
Chronic alcohol excess
What are other causes of chronic pancreatitis?
Conditions obstructing the pancreatic duct:
Hereditary pancreatitis (defect in the trypsinogen gene)
tropical calculus pancreatitis related to malnutrition
What is the commonest carcinoma of the pancreas?
What is the most important risk factor for pancreatic carcinoma?
What is the prognosis for pancreatic carcinoma?
What are symptoms of pancreatic carcinoma?
Symptoms occur at a late stage
They include weight loss and obstructive jaundice