Primary Sclerosing Cholangitis (PSC) is a chronic inflammatory condition that results in the fibrosis and destruction of intra-hepatic and extrahepatic bile ducts. This can lead to cholestasis, hypertension and liver failure.
- 75% of cases are associated with IBD (usually ulcerative collitis). In fact, in some cases, it may present before other features of IBD.
- 5-10% of UC will also have PSC
- 1% of Crohn’s patients will have PSC
- Genetic component – associated with HLA A1-B8-DR3 variant. This variant is associated with other autoimmune diseases (e.g. autoimmune hepatitis).
- Male predominance (2:1)
- Average age of onset: 25–40
There are screening programs for those with IBD to detect the condition at an asymptomatic stage (LFT’s are tested). In others, it may present with:
- Pruritis (itch)
- RUQ pain
- Weight loss
- Acute cholangitis – rare but can occur, typically after a medical procedure involving insertion of equipment into the biliary tree (e.g. ERCP)
- Hepatomegaly / splenomegaly – approx 50% of patients
- P-ANCA – a serum antibody is found in 60% of cases
- LFT’s: ↑ALP, ↑bilirubin
- MRCP / ERCP – are able to visualise bile ductal abnormalities. ERCP is more sensitive than MRCP but obviously more invasive. Small but still clinically significant lesions may be missed.
- Irregularly shaped lumens of intra and extrahepatic ducts can be seen
- Liver Biopsy – histology used to confirm the diagnosis:
- Scar tissue Classical ‘onion skin’ appearance of scars around the bile ducts
- Wide range of changes depending on stage of the disease from mild inflammatory infiltrate, to cirrhosis. The condition is slowly progressive.
- Antibodies – ↑IgM in 50% of patients, ↑IgG in 30% of patients
- Cholangiocarcinoma – 20-30% of patients
- Osteoporosis – treated in the normal manner
The course is variable.
- In symptomatic patients, presentation to death (or liver failure) is 12 years on average.
- Asymptomatic patients survive an average of 15 years
- The majority of patients die from liver failure. 30% die from bile duct carcinoma, and a small number die from colonic or UC complications.
- Liver transplantation is the only curative treatment. 5 year survival is 80-90%. PSC can recur in the transplanted liver.
- Other options – in a small minority of patients, the disease is mostly confined to the extra-hepatic ducts, in which case, balloon dilatation and stenting can be done endoscopically to reduce further damage.
- UDCA – a hydrophilic bile acid, used to prevent liver damage by reducing the number of cholestatic liver enzymes. This alters the metabolism of cholesterol and micelles, and makes them break down more readily. The evidence for its use in CF is patchy, but it is thought to reduce cholestasis and aid bile acid reabsoprtion, which help increase liver function.
- However – clinical trials have shown no statistically significant benefit on outcome or symptoms.
- Management of pruritis – cholestrymanine can be used – the dose can be increased until symptomatic relief is achieved.
- Cholangitis – is a major problem. It is often treated with a broad spectrum AB (e.g. ciprofloxacin) , but there is no benefit of antibiotic prophylaxis.
- Fat soluble vitamins – A, D, E, K – vitamin replacement therapy is required in jaundice therapy.
Secondary sclerosing cholangitis
Is a term used to describe a condition with similar pathology, however, where there is a clear predisposing factor, e.g.:
- Previous bile duct surgery resulting in stricture
- Stones in the bile duct, resulting in cholangitis
- AIDS – probably due to CMV infection