Liver Path. - Patterns of Injury Flashcards
What is cirrhosis?
Disruption of hepatic architecture by fibrosis.
Regenerative nodules form.
What cells lay down the collage in cirrhosis?
Stellate cells and portal fibroblasts.
What are 4 patterns of liver injury?
Vascular
Hepatitic
Infiltrative
Cholestatic
Which LFT enzyme is liver predominant?
ALT
Which LFT enzyme is associated with biliary injury?
GGT
Which LFT enzyme is present in, but not specific to the liver?
AST
Is LDH prevalent in the liver?
No.
What process actually releases enzymes from the injured hepatocyte?
Cytoplasmic blebbing.
What kind of injury causes more AST release?
Examples of things that cause this?
Mitochondrial injury.
EtOH, Wilson’s disease
What’s special about the caudate lobe of the liver?
It has independent venous drainage to the IVC.
What happens when venous outflow from the liver is blocked, initially? Symptoms?
Congestion of liver (‘nutmeg liver”)
Pain from liver capsule expanding, hepatomegaly ascites.
Which zone of the liver is first affected by congestion?
Zone 3
What happens to the liver when there’s chronic venous outflow obstruction?
“Cardiac Type Fibrosis”
… perhaps to resist increased forces.
Hepatocyte atrophy.
What’s Budd-Chiari?
Why is this bad?
Venous outflow obstruction that spares caudate:
Liver atrophies except for caudate, which hypertrophies.
This is bad because hypertrophy of the caudate can compress the IVC once large enough.
2 ways to get liver ischemia?
Infarct
Hypotension
Can a liver survive a completely occluded portal vein? What happens?
Yes, initially.
Thrombis remodeling can lead to portal tract venopathy - lots of blockages of portal veins throughout the liver.
(also portal hypertension still happens)
Will blockage of the hepatic portal vein cause ascites?
Nope.
What will die if the hepatic artery gets occluded?
Bile ducts - as these are mainly supplied by hepatic artery bloodflow.
What does a bile duct infarction look like grossly?
“Biloma” with bile contents spewing out.
2 main divisions of hepatitis?
Acute vs. chronic
2 main histological features of a chronic hepatitic pattern of injury?
Lymphocytes
Apoptotic hepatocytes
Biochemical features of a hepatitic pattern of injury?
High AST and ALT.
What does “activity” refer to in chronic hepatitis?
Degree of inflammation and hepatocellular death.
What zone does acetaminophen damage? Why?
Zone 3- because the damage is caused by a toxic metabolite made by P450 metabolism - and Zone 3 has the most P450 activity.
What’s the toxic metabolite of acetominophen called?
NAPQI (more on this later)
What can increase resistance in the liver without fibrosis?
Amyloid
In what zone is most of the fat deposited in alcoholic and non-alcoholic steatosis?
Zone 3
HCV related steatosis is more in Zone 1
What’s cholestasis?
Any impediment of bile flow.
What can you see in histology of cholestasis? (2 things)
Bile plugs
“Feathery degeneration”
In what patterns of liver damage do you see elevated GGT?
Cholestatic
Infiltrative
What’s elevated in a cholestatic pattern of liver disease?
GGT and conjugated / direct bilirubin.
