Diseases of the Biliary Tract and Liver Flashcards
What is liver cirrhosis?
- parenchyme tissue is replaced by scar tissue
- liver becomes smaller
What is the histological definition of liver cirrhosis?
- fibrous collagenous bands between nodules of hepatocytes
- collagen should only be in liver capsule not in parenchyme tissue
What are the 3 most common causes of liver cirrhosis?
1 - alcohol
2 - obesity
3 - hepatitis B and C
If a patient presents with jaundice, but no other symptoms, is this likley to be acute or chronic?
- acute
What 2 places are most affected by jaundice most common in the body?
1 - skin
2 - eyes
Where does biliruben come from?
- yellow pigment formed during catabolism of old RBCs
What cells breakdown old RBCs in the blood to form biliruben?
- macrophages
Once a macrophage has phagocytosed old RBCs, the RBCs are broken down into what?
- globulin = amino acids
- heme = iron (Fe) and Protoporphyrin
Once a macrophage has phagocytosed old RBCs, the RBCs are broken down into their main compounds globulin which creates amino acids and heme, which is then broken down into iron (Fe) and protoporphyrin. What is protoporphyrin then converted into and what happens to this?
- unconjugated biliruben (insoluble in H2O)
- binds to albumin and is transferred to the liver
Once unconjugated biliruben (insoluble in H2O) has bound to albumin and trravels to the liver, what do hepatocytes do with it?
- converted into conjugated biliruben
- pumped into canaliculi and to the gall bladder as bile
What enzyme is responsible for the conjugation of unconjugated bilirubin in the liver?
- uridine 5 diphospho glucuronosyltransferase (UGT)
Once unconjugated biliruben (insoluble in H2O) has been converted into conjugated biliruben in the liver and pumped into canaliculi and to the gall bladder as bile, what happens to it then?
- pumped into GIT with bile
- converted into urobilinogen
- some urobilinogen is converted into stercobilin (makes stool brown)
Once the conjucgated biliruben in the bile has been converted into urobilinogen in the GIT, then some has been converted into stercobilin (makes stool brown). What happens to the rest of the urobilinogen?
- reabsorbed by body and oxidised into urobilin
- transported to liver and kidneys
- gives urine its yellow colour
What are some physical presentations of chronic liver disease, like liver cirrhosis?
- palmer erythema
- spider nevi
- ascites
- hepatolmegly
What are the 5 main things to do when trying to diagnose a patient with liver disease
1 - patients history
2 - clinical examination
3 -blood tests
4 -radiology
5 - gastroscopy
How can chronic liver disease cause low platelets?
- chronic liver disease causes portal hypertension (PH)
- PH push more blood to the spleen
- spleen traps and removes platelets reducing their numbers
Why is it important to understand if a liver disease is acute or chronic?
- different pathologies
What are the 4 basic steps of liver cirrhosis?
1 - normal liver
2 - fatty liver
3 - liver fibrosis
4 - liver cirrhosis
What is liver failure?
- when the liver is unable to function
In liver failure, jaundice can occur, what is this?
- increased concentrations of biliruben in the blood
- yellow pigment in biliruben changes skin colour
In liver failure, there will be a reduction in clotting factors used in the clotting cascade. What clotting factors does the liver produce?
- 2, 7, 9, 10
- remember 2+7=9 then 10
In liver failure, there is a reduction in albumin, what can this cause?
- hypoalbuminaemia
- result in odema
- leukonychia in nails
Liver failure can fresult in encephalopathy, what is this?
- failure to remove toxins from the body
- ammonia builds up
- asterixis flap due to toxins in the brain