Liver Physiology

Question 1

Which zone of the liver is closest to the porta hepatis

Answer 1

Zone 1 (therefore Zone 3 closest to hepatic vein)

Question 2

What connects portal vein to the hepatic vein

Answer 2

Sinusoids

Question 3

What causes cirrhosis

Answer 3

Any toxin eg alcohol, Hep B virus, autoimmune

Question 4

Cirrhosis characterised by

Answer 4

Parenchymal nodules (fibrotic hepatocytes)

Question 5

Cirrhosis impact on vascular architecture

Answer 5

Pressure build up (= shunts = varices), can eventually result in portal system flowing in reverse direction

Question 6

Most common cause of portal hypertension

Answer 6

Intrahepatic from cirrhosis

Question 7

Ascites

Answer 7

Accumulation of fluid in the abdomen = swelling

Question 8

Impact of portal hypertension on brain

Answer 8

High ammonia in blood = hepatic encephalopathy

Question 9

Places where blood goes when portal hypertension redirects

Answer 9

Spleen = splenomegaly
Oesophagus = varices
Anus = haemorrhoids
Umbilicus = Carpa medusa

Question 10

Hepatitis A severity

Answer 10

Benign, cold-like, doesnt cause cirrhosis

Question 11

Is hepatitis a synonym of cirrhosis

Answer 11

Chronic hepatitis CAN lead to cirrhosis, but not always

Question 12

Hepatitis B severity

Answer 12

In most cases subclinical/acute

BUT when chronic = high rate of death, and since very common disease, still many deaths even though most nerve become chronic

Question 13

Hepatitis C severity

Answer 13

Uncommon but very high percentage becomes chronic = fatal

Question 14

Type of cancer Hep B/ Hep C can lead to

Answer 14

Hepatocellular carcinoma

Question 15

What is a predictable hepatotoxin

Answer 15

We know it will cause harm to the liver (eg paracetamol) but the benefit outweighs the harm, when given in right dosage

Question 16

Even if a chemical isn’t directly hepatotoxic, how can it still cause liver harm

Answer 16

Liver metabolically converts to an active toxin

Question 17

Most common cause of acute liver failure

Answer 17

Paracetamol

Question 18

Most common cause of chronic liver failure

Answer 18

Alcohol

Question 19

Acute alcoholic liver disease results in

Answer 19

Hepatitis (-> cirrhosis if repeated attacks)

Question 20

Chronic alcoholic liver disease results in

Answer 20

Steatosis (-> cirrhosis if continued exposure)

Question 21

Steatosis

Answer 21

Fatty liver

Question 22

How does alcohol result in Steatosis

Answer 22

Chnages in lipid metabolism

Question 23

Non-alcoholic fatty liver disease causes

Answer 23

Obesity, diabetes, hypertension etc

Question 24

Haemachromatosis

Answer 24

Excessive iron in liver

Question 25

WHo gets haemochromatosis

Answer 25

People with genetic defect (everyone else excretes excess iron)