Primary Sclerosing Cholangitis

Question 1

define primary sclerosing cholangitis?

Answer 1

A chronic cholestatic liver disease characterised by progressive inflammatory fibrosis and obliteration of intrahepatic and extrahepatic bile ducts

Question 2

outline the pathogenesis of primary sclerosing cholangitis?

Answer 2

Inflammation and injury of the medium- and large-sized bile ducts, leading to fibrosis and multi-focal stricturing of the ducts

Obstruction of the medium- and large-sized bile ducts leads to progressive fibrosis and ultimately obliteration of the smaller ducts (ductopenia) and bile stasis (cholestasis). Bile stasis above strictures predisposes patients to primary bile duct stones and retained bile salts may further contribute to bile duct damage.

Portal oedema

Bile duct proliferation

Expansion of portal tracts

Progressive fibrosis

Development of biliary cirrhosis

Question 3

outline the aetiology of primary schlerosing cholangitis?

Answer 3

UNKNOWN

Possible immune and genetic predisposition with environmental triggers

Close association with inflammatory bowel disease (especially ulcerative colitis)

IMPORTANT: ulcerative colitis is present in about 70% of patients with PSC

Question 4

what are the risk factors for PSC?

Answer 4

male sex

inflammatory bowel disease (IBD)

genetic predisposition

Question 5

Summarise the epidemiology of PSC?

Answer 5

Usually presents between 25-40 years of age

Relatively rare

M:F is 2:1

Question 6

What are the presenting symptoms of PSC?

Answer 6

May be asymptomatic and diagnosed after persistently raised ALP

May present with:

• Intermittent jaundice
• Pruritis
• RUQ pain
• Weight loss
• Fatigue
• fever and rigors caused by acute cholangitis (but this is less common)

In late stage – symptoms of cirrhosis and ascending cholangitis

IMPORTANT: check for a history of ulcerative colitis

Question 7

What are the signs of PSC OE?

Answer 7

May have no signs

Jaundice

Hepatosplenomegaly

Spider naevi

Encephalopathy

Palmar erythema

Ascites

Question 8

What are the appropriate investigations for PSC?

Answer 8

Blood

ERCP

MRCP

Question 9

what investigation would you consider for PSC?

Answer 9

Liver biopsy

confirm dignosis and allows staging

shows fibrous obliterative cholangitis

Question 10

describe the bloods for PSC?

Answer 10

LFTs:

• High ALP + GGT
• Mildly elevated ALT + AST
• Low albumin + high bilirubin(later stages)

FBC

• Thrombocytopenia
• anaemia
• leukopenia
• PTT high

Serology

• IgG high in children
• IgM high in adults
• No specific antibody
• ANCA may be present
• ASMA and ANA present in 30%
• Anti-mitochondrial antibodies (AMA) usually ABSENT
• Perinuclear anti-neutrophil cytoplasmic antibodies (pANCA) present in 70%

Question 11

What does the ERCP show in PSC?

Answer 11

beaded appearance

Distinguishes large duct from small duct disease

Shows stricturing and interspersed dilation of intrahepatic and (occasionally) extraheptic bile ducts

Small diverticuli on the common bile duct may be seen

Question 12

what does MRCP enable in psc diagnosis?

Answer 12

non-invasive imaging of the biliary tree

Question 13

Give a typical presentation for PSC?

Answer 13

UC/cholangiocarcinoma, male 40-50yrs, beads on a string (MRCP)

“onion skin” fibrosis with increased lymphocyte infiltration

Question 14

What are the differences between PSC and PBC?

Answer 14