The Liver

Question 1

How is bile produced?

Answer 1

• Hb breakdown = billirubin
• unconjugated bilirubin binds to albumin + circulates > Liver
• conjugated to glucuronic acid in hepatocytes
  = water soluble > excreted in bile >

Question 2

What triggers production of more bile from Liver?

Answer 2

I cells release CCK (stim. by. fat) > tiggers production, GB contraction + spinchter of Oddi relaxation

Question 3

What is the functional unit of Liver?

Answer 3

Lobule or Acinus

Question 4

What is found in the centre of each acinus?

Answer 4

Portal triads = portal vein, hepatic artery + bile duct

Question 5

What is found at the periphery of each acinus

Answer 5

Central vein

Question 6

Name the main differences between zone 1 & zone 3 hepatocytes

Answer 6

Zone 1
- better blood supply 
- less vulnerable ischaemia + toxins 
Zone 3 
- less well oxygenated
- more vulnerable poor perfusion + toxins 
- necrosis more likely

Question 7

What LFT’s indicate hepatocyte damage?

Answer 7

High ALT, AST, YGT
Low albumin in chronic
Low proteins in chronic

Question 8

What LFT’s indicate biliary obstruction?

Answer 8

High bilirubin + Alk phos
Impaired protein synthesis + deranged clotting
Low Vit K (requires bile for absorption)

Question 9

Whats the difference between acute and chronic liver disease?

Answer 9

Acute - rapid deterioration, hepatocyte necrosis + inflam

Chronic - continued inflam > fibrosis > permanent scarring

Question 10

What are the liver patterns of injury in chronic hepatitis?

Answer 10

• fatty change
• cholestasis = obstruction of biliary tract
• hepatocyte necrosis
• fibrosis - end stage = cirrhosis
• storage abnormalities - Fe, Cu, glycogen + lipids

Question 11

What are the common causes of Liver disease?

Answer 11

common = alcohol, viral hep, non-alcoholic fatty liver disease (obesity + preg)

Question 12

What are the markers of acute and chronic disease?

Answer 12

IgM = acute 
IgG = chronic

Question 13

Describe Hep A

Answer 13

• RNA enterovirus
• faeco-oral
• fever, malaise, jaundice

Question 14

Describe Hep B

Answer 14

• DNA
• parenteral (blood, semen, saliva)
• can only cause infection in presence of Hep D
• high rate of developing cirrhosis

Question 15

What does HBeAg indicate?

Answer 15

High infectivity + severity of Hep B

Question 16

What is higher in alcoholic liver disease in comparison to

other causes of liver damage?

Answer 16

High AST:ALT

Question 17

What is autoimmune hepatitis

Answer 17

Liver cell necrosis + build up of plasma cells in liver

ANA + antiSM +ve

Question 18

What is primary liver cirrhosis

Answer 18

Granulomatous destruction of bile ducts

AMA +ve

Question 19

Name a few genetic Liver diseases

Answer 19

• Hemochromatosis - v high Fe absorption = thalassaemia
• Wilson’s = failure excrete Cu
• Alpha-1 antitrypsin deficiency = accumulation alpha-1at > emphysema

Question 20

What is the presentation of obstructive jaundice?

Answer 20

• Pale stools - impaired vit K + fat absorption
• Itching - accumulation bile salts + biliary tree
• Dark urine - high conjugated bilirubin
• High ALP

Question 21

What are the 2 types of gallstones?

Answer 21

1. Cholesterol stones

2. Pigment stones

Question 22

What causes cholesterol stones?

Answer 22

• obesity, female + old age = increased cholesterol = GS

- oestrogen malabsorption = low bile salts = GS

Question 23

What causes pigment stones?

Answer 23

• increased RBC breakdown = increased conjugated bilirubin > PS
• chronic biliary infection = glucuronidase production > PS

Question 24

Why is the liver vulnerable to metastases?

Answer 24

Dual blood supply

Large bowel gives rise to metastatic LD as portal vein takes blood from here