Primary Biliary Cirrhosis

Question 1

What causes primary biliary cirrhosis?

Answer 1

AI condition leading to inflammation of intralobular bile ducts i.e. Canals of Hering leading to cholestasis and increased back pressure due to obstruction which leads to fibrosis and cirrhosis

->effector T cells (CD4+) destroy intrahepatic bile ducts

Question 2

What 3 chemicals build up in PBC and why? How would they manifest clinically?

Answer 2

CHOLESTEROL
Xanthelasma (periorbital cholesterol deposits)
Cholesterol deposits in BV= increased CVD risk

BILE ACIDS
Cause itching
Greasy/fatty stools

BILIRUBIN
Jaundice
Pale stools

Build up due to normally being excreted by the bile ducts into intestines but obstruction in PBC means this is not possible

Question 3

What changes to the stool can occur with cholestasis and why?

Answer 3

Bile acids not present to aid with fat digestion and absorption= greasy stools
Pale stools due to bilirubin normally causing stool to be dark

Question 4

Who is more likely to present with PBC? What will they present with?

Answer 4

Middle aged women (x9 men)
People with AI conditions i.e. thyroid or coeliac
Rheumatoid conditions

Fatigue 
Pruritus
GI disturbance 
Jaundice 
Pale stools 
Xanthoma or xanthelasma 
Ascites/splenomegaly/ spider naevi (signs of liver failure)

Question 5

How will the LFTs be effected and why?

Answer 5

Raised ALP due to being obstructive biliary

Bilirubin will rise later in disease

Question 6

What additional blood tests can be done to diagnose PBC?

Answer 6

Anti-mitochondrial antibodies= most specific
Anti-nuclear antibodies

Raised ESR
Raised IgM

Question 7

How can PBC be treated?

Answer 7

NO CURE

Ursodeoxycholic acid

• synthetic bile salt
• decreased GI absorption of cholesterol

Cholestyramine= bile acid sequestrate i.e. prevents bile acid absorption in gut to help prevent pruritus

Immunosuppressants i.e. steroids

Liver transplant-> PBC can reoccur and require re-transplantation

Question 8

What is the mechanism of action of ursodeoxycholic acid (UDCA)?

Answer 8

Decreases the cholesterol content of bile by reducing the hepatic synthesis and secretion of cholesterol and fractional reabsorption of cholesterol by intestine

Question 9

What is the escalation of TX for puritis?

Answer 9

Cholestyramine

Rifampicin-> need to monitor LFTs as enzyme inducer so can cause drug-induced hepatitis

Sertraline

Naltrexone

UV light therapy

Nasobiliary drainage

Transplant

Question 10

What can PBC progress to and how would it present?

Answer 10

Advanced liver cirrhosis + portal hypertension

• symptomatic pruritus
• fatigue
• steatorrhoea
• distal renal tubular acidosis
• hypothyroidism
• osteoporosis
• hepatocellular carcinoma