- Clinical science
Primary sclerosing cholangitis (PSC) is a progressive chronic inflammation of both the intrahepatic and extrahepatic bile ducts. While the exact etiology is unknown, there is a strong association with autoimmune diseases, particularly ulcerative colitis (UC). In the early stages, PSC is usually asymptomatic. Later in the course of the disease, patients present with symptoms of cholestasis (e.g., pruritus, jaundice). Laboratory abnormalities include elevated liver function tests and autoantibodies (pANCA in up to 80% of cases). Magnetic resonance cholangiopancreatography (MRCP) or endoscopic retrograde cholangiopancreatography (ERCP) is performed to confirm the diagnosis. Management is primarily symptomatic, with liver transplantation reserved for end-stage liver disease.
- Sex: ♂ > ♀ (2:1)
- Age: The median age at diagnosis is ∼ 40.
Epidemiological data refers to the US, unless otherwise specified.
- Chronic inflammatory bowel diseases (IBD)
- HLA-B8 and HLA-DR3
- Other autoimmune conditions (e.g., hypergammaglobulinemia IgM)
The majority of PSC patients also have ulcerative colitis! References:
- Often initially asymptomatic
- Signs of cholestasis
- Later stages: signs of
- Symptoms of chronic inflammatory bowel disease, which is frequently associated with PSC, or other associated comorbidities
- Perinuclear (pANCA) are present in up to 80% of cases
- ↑ ALP, GGT, conjugated bilirubin
- Potentially, ↑ transaminases (however, they are usually < 300 U/L)
- Method of choice: magnetic resonance cholangiopancreatography (MRCP)
- Findings: multifocal strictures alternating with dilation and beading of bile ducts
- Irregular diameter of the bile duct
- Diffuse thickening of the wall of the common hepatic and bile ducts
- Following diagnosis → colonoscopy (to assess for UC)
- Not an essential part of the workup; usually done if small duct PSC is suspected, which is not always detectable via cholangiography
- Typical finding: "onion skin" scarring and fibrosis of bile ducts
|Differential diagnoses of primary cholangitis|
|Primary sclerosing cholangitis||cholangitis|
|Epidemiology|| || |
|Pathophysiology|| || |
|Associated conditions|| |
The differential diagnoses listed here are not exhaustive.
- Ursodeoxycholic acid and immunosuppressives (e.g., tacrolimus): may decrease transaminases, ALP, and serum bilirubin, but do not prevent disease progression
- Treatment of pruritus (e.g., cholestyramine, rifampicin, naltrexone)
- Supplementation of fat-soluble vitamins (see “Complications” below)
- In the case of bile duct stenosis: ERCP with duct dilation; potentially, stent placement
- Surgical: Liver transplantation is the only curative option and is performed in the case of advanced liver cirrhosis.