Primary sclerosing cholangitis is a condition where the intrahepatic or extrahepatic ducts become strictured and fibrotic. This causes an obstruction to the flow of bile out of the liver and into the intestines. Sclerosis refers to the stiffening and hardening of the bile ducts, and cholangitis is inflammation of the bile ducts. Chronic bile obstruction eventually leads to liver inflammation (hepatitis), fibrosis and cirrhosis.
The cause is mostly unclear although there is likely to be a combination of genetic, autoimmune, intestinal microbiome and environmental factors. There is an established association with ulcerative colitis, with around 70% of cases being alongside established ulcerative colitis.
- Aged 30-40
- Ulcerative Colitis
- Family History
- Chronic right upper quadrant pain
Liver Function Tests
Liver function tests show a “cholestatic” picture. This means alkaline phosphatase is the most deranged LFT and may be the only abnormality at first.
There may be a rise in bilirubin as the strictures become more severe and prevents bilirubin from being excreted through the bile duct. Other LFTs (i.e. transaminases: ALT and AST) can also be deranged, particularly as the disease progresses to hepatitis.
No antibodies are highly sensitive or specific to PSC. They aren’t very helpful in diagnosis but they can indicate where there is an autoimmune element to the disease that may respond to immunosuppression.
- Antineutrophil cytoplasmic antibody (p-ANCA) in up to 94%
- Antinuclear antibodies (ANA) in up to 77%
- Anticardiolipin antibodies (aCL) in up to 63%
The gold standard investigation for diagnosis is an MRCP, which is short for magnetic resonance cholangiopancreatography. This involves an MRI scan of the liver, bile ducts and pancreas. In primary sclerosis cholangitis it may show bile duct lesions or strictures.
Associations and complications
- Acute bacterial cholangitis
- Cholangiocarcinoma develops in 10-20% of cases
- Colorectal cancer
- Cirrhosis and liver failure
- Biliary strictures
- Fat soluble vitamin deficiencies
Liver transplant can be curative but is associated with its own problems (around 80% survival at 5 years).
- ERCP can be used to dilate and stent any strictures
- Colestyramine is a bile acid sequestrate in that it binds to bile acids to prevent absorption in the gut and can help with pruritus due to raised bile acids
- Monitoring for complications (such as cholangiocarcinoma, cirrhosis and oesophageal varices)
ERCP (Endoscopic Retrograde Cholangio-Pancreatography) involves inserting a camera through the persons throat, oesophagus, stomach and duodenum to the a point in the duodenum where the bile ducts empty into the GI tract. They then go through the sphincter of Oddi and into the ampulla of Vater. From the ampulla of Vater they can enter into the bile ducts and use X-rays and injecting contrast to identify any strictures. These strictures can then be dilated and stented during the same procedure providing improved flow through those ducts and an improvement in symptoms.
Last updated January 2019