Primary sclerosing cholangitis (PSC)
A disease of unknown aetiology in which chronic inflammation of the bile ducts leads to stricture formation and progressive obstructive jaundice.
Peak 25–40 years.
M > F
The cause is unknown but there is a strong association with HLA haplotype (HLA-B8, DR-3, DR-2 and DR-52a). There is also a strong association with inflammatory bowel disease, which is present in 60–75%, but may be asymptomatic. Also associated with HIV infection.
Chronic inflammation of the intra- and extrahepatic bile ducts leads to fibrosis and short strictures form which obstruct the passage of bile. Chronic obstruction leads to jaundice and cirrhosis develops over about 10 years.
Patients usually present with progressive jaundice and pruritus or ascending cholangitis.
Endoscopic retrograde cholangiopancreatography (ERCP) shows a beaded appearance of the large bile ducts. Liver biopsy is diagnostic demonstrating concentric, (onionskin) fibrosis around medium-sized bile ducts, including those in portal tracts. Small bile ducts scar and vanish.
Corticosteroids, azathiporine and methotrexate have been tried, but have no proven benefit. Drainage is usually ineffective. Liver transplantation is used in advanced cases.
Slowly progresses to chronic liver disease with risk of fulminant hepatic failure, cholangiocarcinoma and hepatocellular carcinoma. There is an increased risk of colon cancer.