Primary biliary cirrhosis

Question 1

What is Primary biliary cirrhosis (PBC)?

Answer 1

PBC = chronic inflammatory liver disease characterised by progressive destruction of intrahepatic bile ducts (occurring in the context of chronic portal tract inflammation) leading to cholestasis and ultimately cirrhosis

Question 2

What is the aetiology of PBC?

Answer 2

Autoimmune is highly likely
o AMA - Anti-mitochondrial Abs found in 95%
o High chance of personal/FH autoimmune disease

Combination of environmental and genetic factors have also been proposed
o Trigger = infection, chemical, toxin
o In susceptible individuals, may lead to a T-cell mediated AI response

Question 3

What are the risk factors for PBC?

Answer 3

• Female, aged 45-60 y/o
• FH/personal history of PBC/AI
• Smoking

Question 4

What is the epidemiology of PBC?

Answer 4

• 10-20 in 100,000
• Usually affects middle aged women (55-65 y/o)

9x more common in females

Question 5

What are the symptoms of PBC?

Answer 5

Can be asymptomatic - incidental finding on blood tests (raised ALP, cholesterol) (50%)

Insidious
o Fatigue
o Weight loss
o Pruritus

Complications - decompensation
o Jaundice
o Ascites
o Variceal haemorrhage

Symptoms of associated conditions
o Sjögren’s syndrome – dry eyes, dry mouth
o Arthritis
o Raynaud’s phenomenon

Question 6

What are the signs of PBC?

Answer 6

Early - May be no signs

Late – liver + biliary disease
o	Jaundice
o	Skin pigmentation
o	Excoriations 
o	Xanthomas – secondary to hypercholesterolaemia 
o	Hepatomegaly
o	Ascites

Signs of chronic liver disease
o Spider naevi
o Palmar erythema
o Clubbing

Question 7

What are the investigations for PBC?

Answer 7

Bloods
LFTs:
ALP: Raised
GGT: Raised
AST/ALT: Normal initially, then raises with disease progression
Bilirubin: Normal initially, then raises with disease progression
Albumin: Low

o     Clotting screen -  PT prolongation
o	Serology - AMA positive - diagnostic
o	Cholesterol: Raised
o	TFTs
o	Bone screen: Plasma calcium, phosphate, 25-vitD

US – must exclude first
o Exclude extrahepatic biliary obstruction (gallstones, strictures)

Biopsy
o Chronic inflammatory cells and granulomas around the intrahepatic bile ducts
o Destruction of bile ducts
o Fibrosis and regenerating nodules of hepatocytes

DEXA
o If suggested by bloods