Primary sclerosing cholangitis Flashcards
Define primary sclerosing cholangitis.
Chronic cholestatic liver disease characterised by progressive inflammatory fibrosis and obliteration of intrahepatic and extrahepatic bile ducts.
What is the aetiology of PSC?
Unknown
It has auto-antibodies BUT does not behave like autoimmune disease as it is male predominant (2:1) and does not respond to immunosuppressive treatment
Link with IBD could be related to translocation of lymphocytes in colon via enterohepatic circulation
What is the pathophysiology of the bile ducts in PSC?
- Inflammation of medium and large bile ducts →
- periductal fibrosis and strictures →
- eventually obliteration or smaller ducts and cholestasis
- This predisposes to jaundice, pruritus and episodes of bacterial cholangitis and progression to biliary cirrhosis
How common is PSC and when does it present?
2-7/100,000
Usually presents between age 25-40yrs
What are the symptoms of PSC?
Clinical features range from asymptomatic (50%) to end-stage liver disease.
- Fatigue
- Abdominal pain RUQ/epigastrium
- Pruritus - intermittent generalised
- Liver disease - jaundice, steatorrhoea, haematemesis, encephalopathy, ascites
- IBD - UC or Crohn’s in 80%
- Weight loss - from fat malabsorption
- Episodes of fever and rigors - caused by acute cholangitis, but less common
What are the risk factors for PSC? How common is IBD in PSC?
- Male (2:1)
- Age 40-50yrs
- IBD - 80% of patients with PSC have IBD, but 10% of IBD patients have PSC
- FH
What are the signs of PSC on examination?
May have no signs
In more advanced disease:
- jaundice
- hepatosplenomegaly
- spider naevi
- palmar erythema
- ascites
- encephalopathy
What investigations would you do in PSC?
Bloods:
- LFT - cholestatic pattern
No auto-antibodies specific to PSC but may have ANA, ANCA, anti-SMA, RF.
Later: thrombocytopenia and clotting abnormalities
Other tests of exclusion: immunoglobulin levels, urine copper, ceruloplasmin
Imaging
- USS - good initial test but not best for looking at biliary tree
- Abdo CT - thickening of ducts, saccular intrahepatic duct dilation, lymphadenopathy.
- MRCP - enables non-invasive imaging of biliary tree. ERCP is done if MRCP is not diagnostic.
Invasive
- Colonoscopy
- Liver biopsy - supports diagnosis but rarely diagnostic. Shows fibro-obliterative cholangitis, periductal fibrosis and inflammation.
NB: high risk of cholangiocarcinoma.
What are the complications of PSC?
- cholangitis
- biliary cirrhosis
- cholangiocarcinoma
- portal hypertension
- metabolic bone disease
How do you manage PSC?
Early disease - observation + pruritus relief (e.g. colestyramine)
Vitamin D + calcium, bisphosphonates + HRT - protect against hepatic osteodystrophy
Liver transplantation - but may get graft recurrence in 10-20%
May have overlap with other autoimmune conditions for which you would immunosuppress but this for PSC alone does not work.
What should you monitor for in PSC?
- Progression of cirrhosis with LFTs
- Bone mineral density - hepatic osteodystrophy
- Fat- soluble vitamin testing
- CT/MRI for HCC every 6 months
- IBD colonoscopy for colorectal cancer
What is the prognosis with PSC?
Results in progressive hepatic fibrosis, and ultimately cirrhosis and end-stage liver disease for most patients.
Reduced life expectancy - death from cholangiocarcinoma especially.
