L18 - Biliary disease / Gall stones Flashcards
Biliary colic
Increase in gall bladder wall tension which produces a characteristic type of pain.
Blockage of outflow of bile during gallbladder contraction.
Cystic duct obstruction for a few hours may lead to…
Acute gall bladder inflammation: acute cholecystitis
Choledocholithiasis
Presence of one or more gallstones in the common bile duct.
Gall stone in ampulla of Vater might cause
Abdominal pain, jaundice
Stagnant bile above obstructing bile duct can become infected.
- bacteria can spread rapidly back up the ductal system to liver
- produces life threatening ascending cholangitis
Obstruction of pancreatic duct results in
Activation of pancreatic digestive enzymes within pancreas - leads to acute pancreatitis
Chronic cholecystitis
Progressive fibrosis and loss of function of gallbladder.
Pre-disposes to gall bladder cancer
Cholesterol gall stones
Liver cells secrete cholesterol and lecithin phospholipids into bile.
Cholesterol supersaturation of bile appears to be a pre-requisite for gall stone formation.
How does cholesterol come into solution
Cholesterol (usually insoluble) comes into solution by forming vesicles with phospholipid (lecithin)
Gall stone formation
Nucleation: transition of cholesterol from soluble state to crystalline form.
Mucin hypersecretion by gall bladder mucosa creates a visoelastic gel that fosters nucleation.
Gall bladder hypomobility and bile stasis promotes growth and formation of gall stones
Acute calculous cholecystasis
- inflammation of gall bladder, develops in setting of obstructed cystic or bile duct
- nausea / vomitting
Mirizzi syndrome
Impacted stone in cystic duct causes extrinsic compression which obstructs the common hepatic duct.
Acute acalculous cholecystitis
Inflammed gall bladder in absence of obstructed cystic or bile duct
Cholangitis
Infection in biliary system
Charcot triad (cholangitis)
- Fever
- Right upper quadrant pain
- Jaundice
Organisms causing cholangitis
E.coli Streptococcus Faecalis Clostridium Enterbacter Psuedomonas
Recurrent pyogenic cholangitis
- Initiated by parasitic infestation of the biliary ducts by opisthorchis sinensis
- Bile stasis, secondary bacterial infection, pigment stones form around
Primary sclerising cholangitis
- non-suppurative inflammation and fibrosis of the biliary duct system
- fatigue, pruiritus and jaundice
- progressive destruction of bile duct, leading to cirrhosis and liver failure
Primary biliary cholangitis
- primary cholestatic biliary disease that presents with fatigue and itching
- fatigue, itching, asymptomatic elevation of alkaline phosphatase.
- Jaundice: progressive destruction of bile ductules that eventually lead to liver cirrhosis and hepatic failure
What might be seen on physical examination of a patient with biliary disease?
Vital signs
- tachycardia, hypotension suggests hypovolemia, presence of sepsis
Yellow discolouration of skin - indirect hyperbilirubinaemia Orange hue - hepatocellular jaundice Dark green tint - prolonged biliary obstruction
Xanthoma
Irregular yellow patch or nodule on skin, caused by deposition of lipid.
Hyperbilirubinaemia may have what effect on the eyes
Scleral icterus
Yellow discolouration of white of eyes.
Describe formation of bilirubin
- break down product of haem
- unconjugated bilirubin hydrophobic and transported in blood reversibly to albumin
- taken up by hepatocyte
- converted to conjugated bilirubin by glutamyl transferase
- actively secreted into the biliary canaliculi
Where is alanine aminotransferase found
In cardiac and skeletal muscle, renal and cerebral nerve cells.
Increase in ALT suggests liver injury
Iatrogenic injury
Tissue / organ damage caused by necessary medical treatment
Summarise liver function tests
Bilirubin Aminotransferases - leaks on damage to hepatocytes Alkaline phosphatase - also present in bone Gamma glutamyl transferase
Conjugated bilirubin in bile is converted to…
Bilirubin —-bacterial proteases—- urobilogen
Urobilogen (white)——–stercobilinogen (brown) (excreted)
Where is stercobilinogen excreted from?
Kidneys
Pre-hepatic Jaundice
Increased rate of haemolysis (breakdown of RBCs).
Results to an increase in amount of unconjugated bilirubin present in blood, deposition of this can lead to a jaundiced appearance.
When is the only time that bilirubin found in urine?
Post-hepatic jaundice.
Investigations of Jaundice
Blood
Secretions (urine)
Radiology
Endoscopy
Compare primary sclerosing cholangitis and primary biliary cirrhosis
PSC
- inflammation
- affecting intra and extra hepatic ducts
PBC
- chronic cholestasis
- affecting intrahepatic ducts
-
Compare secondary sclerosing cholangitis and secondary biliary cholangitis
SSC
- chronic obstruction form a defined pathology
- affects intra and extra hepatic ducts
- rare
SBC
- chronic obstruction
- extra hepatic ducts
- main bile duct obstruction
Cholangiocarcinoma
Adenocarcinoma of the bile duct. Location: - peripheral - hilar (most common) - distal
Cholecystolithiasis
Inflamed gall bladder.
Symptoms
- biliary colic
- cholecystitis
- mucocoel
- empyema
- perforation
- cancer
Empyema
Cavity filled with pus
Choledocolithiasis
Stone in bile duct.
- acute pancreatitis
- cholangitis
- Mirizzi syndrome
- gall stone ileus
Mirizzi syndrome
Gall stone becomes impacted in the cystic duct or neck of the gall bladder, causing compression of the common hepatic duct.
Types of Mirizzi syndrome
Type 1: stone stuck in fundus of gall bladder, causes compression of cystic bile duct
Type 2: Cholecystodochal fistula
Type 3 & 4: Increasing size of defect
Gall stone ileus
Rare form of small bowel obstruction caused by an impaction of a gallstone within the lumen of the small intestine.
Calcot’s triangle
Orientated so that its apex is directed at liver. Includes - common hepatic duct - cystic duct - inferior surface of the liver
