Liver Path. - Patterns of Injury

Question 1

What is cirrhosis?

Answer 1

Disruption of hepatic architecture by fibrosis.

Regenerative nodules form.

Question 2

What cells lay down the collage in cirrhosis?

Answer 2

Stellate cells and portal fibroblasts.

Question 3

What are 4 patterns of liver injury?

Answer 3

Vascular
Hepatitic
Infiltrative
Cholestatic

Question 4

Which LFT enzyme is liver predominant?

Answer 4

ALT

Question 5

Which LFT enzyme is associated with biliary injury?

Answer 5

GGT

Question 6

Which LFT enzyme is present in, but not specific to the liver?

Answer 6

AST

Question 7

Is LDH prevalent in the liver?

Answer 7

No.

Question 8

What process actually releases enzymes from the injured hepatocyte?

Answer 8

Cytoplasmic blebbing.

Question 9

What kind of injury causes more AST release?

Examples of things that cause this?

Answer 9

Mitochondrial injury.

EtOH, Wilson’s disease

Question 10

What’s special about the caudate lobe of the liver?

Answer 10

It has independent venous drainage to the IVC.

Question 11

What happens when venous outflow from the liver is blocked, initially? Symptoms?

Answer 11

Congestion of liver (‘nutmeg liver”)

Pain from liver capsule expanding, hepatomegaly ascites.

Question 12

Which zone of the liver is first affected by congestion?

Answer 12

Zone 3

Question 13

What happens to the liver when there’s chronic venous outflow obstruction?

Answer 13

“Cardiac Type Fibrosis”
… perhaps to resist increased forces.
Hepatocyte atrophy.

Question 14

What’s Budd-Chiari?

Why is this bad?

Answer 14

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.

Question 15

2 ways to get liver ischemia?

Answer 15

Infarct

Hypotension

Question 16

Can a liver survive a completely occluded portal vein? What happens?

Answer 16

Yes, initially.
Thrombis remodeling can lead to portal tract venopathy - lots of blockages of portal veins throughout the liver.
(also portal hypertension still happens)

Question 17

Will blockage of the hepatic portal vein cause ascites?

Answer 17

Nope.

Question 18

What will die if the hepatic artery gets occluded?

Answer 18

Bile ducts - as these are mainly supplied by hepatic artery bloodflow.

Question 19

What does a bile duct infarction look like grossly?

Answer 19

“Biloma” with bile contents spewing out.

Question 20

2 main divisions of hepatitis?

Answer 20

Acute vs. chronic

Question 21

2 main histological features of a chronic hepatitic pattern of injury?

Answer 21

Lymphocytes

Apoptotic hepatocytes

Question 22

Biochemical features of a hepatitic pattern of injury?

Answer 22

High AST and ALT.

Question 23

What does “activity” refer to in chronic hepatitis?

Answer 23

Degree of inflammation and hepatocellular death.

Question 24

What zone does acetaminophen damage? Why?

Answer 24

Zone 3- because the damage is caused by a toxic metabolite made by P450 metabolism - and Zone 3 has the most P450 activity.

Question 25

What's the toxic metabolite of acetominophen called?

Answer 25

NAPQI (more on this later)

Question 26

What can increase resistance in the liver without fibrosis?

Answer 26

Amyloid

Question 27

In what zone is most of the fat deposited in alcoholic and non-alcoholic steatosis?

Answer 27

Zone 3 | HCV related steatosis is more in Zone 1

Question 28

What's cholestasis?

Answer 28

Any impediment of bile flow.

Question 29

What can you see in histology of cholestasis? (2 things)

Answer 29

Bile plugs | "Feathery degeneration"

Question 30

In what patterns of liver damage do you see elevated GGT?

Answer 30

Cholestatic | Infiltrative

Question 31

What's elevated in a cholestatic pattern of liver disease?

Answer 31

GGT and conjugated / direct bilirubin.