GI: Diseases of liver, biliary tree and pancreas

Question 1

List the functions of the liver

Answer 1

• detoxification, metabolism of drugs/ toxins
• energy metabolism
• storage of glycogen (buffers blood sugar)
• protein synthesis, albumin and clotting factors
• produces bile

Question 2

List the functions of the pancreas

Answer 2

Endocrine - produces insulin and glucagon

Exocrine - produces digestive enzymes

Question 3

List the functions of the gall bladder

Answer 3

• stores and concentrates bile

- excretes bile pigments

Question 4

Explain why a diseased liver would cause:
Poor blood clotting
Skin irritation
Ascites

Answer 4

Poor blood clotting - insufficient clotting factors synthesised, bleed easily
Skin irritation - bile salts circulating and depositing on the skin can cause itching
Ascites - not enough albumin produced so low oncotic pressure

Question 5

Outline the steps involved in excretion of bilirubin

Answer 5

Bilirubin bound to albumin which carries it to the liver
It is then conjugated to make it soluble, and joins with bile pigments and bile salts
This then drains into the biliary tree and is converted to urobilinogen in the duodenum
Urobilinogen and sterobilinogen make poo brown

Question 6

What is pre-hepatic jaundice?

Answer 6

The liver is normal but overworked so cannot conjugate fast enough!
There is increased bilirubin load to the liver eg haemolytic anaemia, the unconjugated bilirubin remains in blood circulation

Question 7

What is hepatic jaundice?

Answer 7

There is injury/damage to the liver so decreased rate of conjugation.

Question 8

What is post-hepatic jaundice?

Answer 8

There is obstruction to bile drainage into the duodenum eg gallstones in common bile duct, pancreatic cancer, hepatocyte swelling.
The bilirubin in conjugated and refluxes into the circulation but doesnt make it into the stool - steathorrhoea.

Question 9

What are the liver function tests?

Answer 9

Give an indication of liver damage rather than function
Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) - in hepaTocytes
Alkaline phosphatase (ALP) - in the cells lining the bile ducts

Question 10

What is hepatitis and what are the causes?

Answer 10

Hepatitis: hepatocyte inflammation and break down 
Viral eg Hep A B C
Autoimmune
Drugs eg paracetamol, alcohol
Hereditory disorders

Question 11

What is fatty liver and what are the causes?

Answer 11

Steatosis is fat in the liver and steatohepatitis is the fat causing an inflammatory response. It is reversible!
The main cause is alcohol, however there are other causes of fatty liver disease eg high cholesterol, obesity

Question 12

What are the most common types of malignancy in the liver?

Answer 12

Liver metastases is more common than primary - 50% come from colorectal cancers.
Most common primary malignancy is hepatocellular carcinoma

Question 13

How does chronic liver disease lead to cirrhosis and what is the complication of this?

Answer 13

Chronic inflammation of the liver leads to ongoing necrosis and fibrosis. There is therefore an irreversible change to the liver structure - cirrhosis (shrunken nodular irregular liver)
The increases resistance to blood flow that leads to portal hypertension.

Question 14

What is biliary colic and cholecystitis?

Answer 14

Impaction of gallstones in the biliary tree leading to nausea and vom, abdo pain, jaundice, fever, right upper quadrant tenderness.
Cholecystitis is when the gall bladder gets inflamed and infected.

Question 15

Outline the causes, presentation and treatment of acute pancreatitis

Answer 15

Acute pancreatitis is damage to acinar cells which release enzymes. Most common causes are gallstones and alcohol.
Presents with severe pain, vom and hypotension.
Treatment is supportive - analgesics, IV fluids and mortality is significant (10%)

Question 16

What is the most common malignancy of the pancreas?

Answer 16

Ductal adenocarcinoma - the main risk factor is smoking.
Presents late with vague symptoms so prognosis is v v poor
- obstructive jaundice
- malabsorption
- pain, weight loss, vomiting