Liver Failure and Jaundice

Question 1

What is the biliary tree

Answer 1

The structures responsible for transit and storage of bile

Question 2

Define jaundice

Answer 2

describes the yellow discolouration of sclerae and skin due to raised bilirubin.
Detectable clinically when serum bilirubin >40µmol/litre.

Question 3

What are the 3 main types of jaundice

Answer 3

Haemolytic jaundice
Jaundice caused by congenital hyperbilirubinamias
Cholestatic jaundice

Question 4

Describe haemolytic jaundice

Answer 4

Pre-hepatic (before bilirubin reaches the liver)
Anaemias e.g. SCD, haemolysis, transfusion, haematoma resorption
Increase in break down of RBCs, increased unconjugated bilirubin production
Liver is normal
Increase in serum bilirubin

Question 5

Describe jaundice caused by congenital hyperbilirubinaemia

Answer 5

Hepatic
Impaired conjugation of bilirubin OR bilirubin handling by the liver
Common = Gilbert’s syndrome

Question 6

Describe Gilbert’s syndrome

Answer 6

Autosmal recessive
2-7% of population
Mutation in gene coding for UDP-glucoronyl transferase
Increase in unconjugated bilirubin
Asymptomatic, mild jaundice may appear under exertion, stress, fasting, infection etc.
Can lead to jaundice via dehydration, fasting and viral illness

Question 7

Describe cholestatic jaundice and what is it characterised by

Answer 7

Post-hepatic
Failure/slow rate of bile secretion by the liver or bile duct obstruction
Characterised by conjugated bilirubin, pale stool, dark urine, abnormal liver biochemistry, sepsis

Question 8

What are the two types of choelstatic jaundice

Answer 8

Intrahepatic cholestasis - caused by hepatocellular swelling or abnormalities at cellular lever of bile excretion.

Extrahepatic cholestasis - from the obstruction of bile flow at any point distal to the bile canaliculi (dilated bile ducts)

Question 9

How does alcohol cause liver disease

Answer 9

Is a hapatotoxin
Fatty change
Alcoholic hepatitis 
Alcoholic cirrhosis 
exact mechanism unknown

Question 10

What are the common causes of liver disease

Answer 10

Alcoholic and non-alcoholic fatty liver disease (developed)

Chronic viral Hep B or C (developing)

Question 11

What are some other signs of liver disease

Answer 11

Hepatic encephalopathy - drowsy, coma due to toxin accumulation
Fetor hepaticus - must sweet breath odour
Hepatic flap - cours hand tremor

Question 12

What is the aetiology of liver cirrhosis

Answer 12

Alcohol (developed) but Hep B and C (developing)

Response to chronic liver injury from any cause

Question 13

What is used to diagnose liver cirrhosis

Answer 13

Liver biopsy

Question 14

What is liver failure

Answer 14

Massive loss of hepatocytes or severe hepatic dysfunction occurring within 6 months of the symptoms of liver disease with clinical manifestation of hepatic encephalopathy or coagulopathy

Question 15

What are the clinical features of acute liver failure

Answer 15

Jaundice
CNS complications
Coagulopathy
Renal failure
Sepsis
Cardiovascular complications
Metabolic complications

Question 16

Describe sepsis due to acute liver failure

Answer 16

bacterial - occurs in 90%
Fungal - 32%
Commonly presents within 3 days of hospital admission
Fever and leucocytosis are absent

Question 17

Describe the CNS complications of acute liver failure

Answer 17

Hepatic encephalopathy

toxin accumulation from the gut induces cerebral oedema -> consciousness and coma

Question 18

Describe renal failure in relation to acute liver failure

Answer 18

hepatorenal syndrome - unexplained renal failure with liver disease or surgery for biliary tract obstruction
Kidneys are normal

Question 19

Describe coagulopathy in relation to acute liver failure

Answer 19

Liver is important for coagulation
Impairs synthesis of coagulation factors I, II, V, VII, IX, X
Factor VII declines first
Fibrinogen only affected in severe disease
Increases fibrinolysis and coagulation
Decreased coagulation factor clearance

Question 20

What suggests a coagulation defect

Answer 20

bleeding at any site
oozing at venepuncture sites - from excessive fibrinolysis
bruising (see photograph

Question 21

Describe chronic liver failure

Answer 21

Deterioration in liver function superimposed on chronic liver disease
Cause may be infection, haemorrhage or electrolyte imbalance , alcohol

Question 22

What can cause post-hepatic jaundice

Answer 22

Gall stones
Cancer
Cholangiocarcinoma

Question 23

Describe the pathophysiology of liver failure

Answer 23

Rate of hepatocyte> regeneration
Apoptosis
Necrosis

Question 24

What are the causes of acute liver failure

Answer 24

Disease of pregnancy e.g. AFLOP, Budd-Chiari
Idiosyncratic drug reactions e.g. NSAIDs
Vascular diseases e.g ischaemic hepatitis
Metabolic causes e.g. Wilson/s