Chronic liver disorders Flashcards
(50 cards)
What does chronic liver disease result from
Hepatocellular injury and necrosis often with a degree of underlying fibrosis of the liver
When does jaundice result
When the liver’s capacity to convert and excrete bilirubin as bile is exceeded
What can jaundice result from
Over production of bilirubin
reduction in the eliminatory capactiy of the liver
What is bilirubin
The breakdown product of haem
Where is bilirubin found
Bound to albumin in the plasma but at the hepatocyte membrane, it dissociates and enters the hepatocyte
What is prehepatic jaundice
increased degradation of haem leading to haem concentrations that cannot be cleared by the normal conjufative mechamisms resultin in predominately unconjugated hyperbilirubinaemia
What is hepatic jaundice
Liver damage and or inflammation affecting the conjugative and excretory ability of the liver so that the normal bilirubin load cannot be excreted. This results in a predominately unconjugated or mixed conjugated and unconjugated hyperbilirubinaemia
What is postheaptic jaundice
Obstruction of the biliary outflow tract at any level, leading to an inability to excrete conjugated bilirubin in bile resulting in a conjugated hyperbilirubinaemia
Is unconjugated bilirubin in water soluble or insoluble
Insoluble (cannot be excreted in urine)
What is conjugated bilirubin converted to in the terminal ileum
Urobilinogen
Bilirubin that is not reabsorbed is further converted to what and what does this do
Urobilin then stercobilin
It gives faeces its normal colour
What gives clues about the cause of jaundice
Observation of the stool and testing for the different byproducts of haem excretion in the blood and urine
What results in pale stool and dark urine
Obstruction of the biliary system
What is portal hypertension defined as
The gradient reaching 12mmHg or greater
What does increased pressure in the portal system result in
Collateral vessel formation Ascites increased risk of hepatorenal syndrome hepatic encephalopathy Splenomegaly
What is the management for portal hypertension
First line is with a non-selective B blocker: propanolol to reduce the pressure within the portal system
What is ascites
The presence of fluid in the peritoneum
What are the two main pathogenic mechanisms for asictes
Transudation and exudation
What are transudates:
Hydrostatic: result of portal hypertension and resultant increases in the pressure in splanchnic vessels
Oncotic: the result of lowered serum albumin as the synthetic function of the liver decreases
Fluid retention: renal hypoperfusion resulting from portal hypertension causes release of renin and hence a secondary hyperaldosteronism; this results in salt and water retention and contributes to ascites
What are exudates
They result from an inflammatroy or neoplastic process at the peritoneal surface causing increased production of peritoneal secretions
What is the function of the Serum-to-ascites albumin gradient
To determine whether ascites is related to transudation or exudation
How is SAAG calculated
Serum albumin conc. - Ascites albumin conc.
What is the general management of ascites
treat the underlying liver condition
Improvement of nutritional status in order to maximise serum albumin
What are the specific management for asicties
Reduction of hydrostatic pressure in the splanchnic vasculature with diuretics - spironolactone!
Abdominal paracentesis - removing the fluid through a drain
