What is primary sclerosing cholangitis (PSC)?

PSC is a disease that damages and blocks bile ducts inside and outside the liver. Bile is a liquid made in the liver. Bile ducts are tubes that carry bile out of the liver to the gallbladder and small intestine. In the intestine, bile helps break down fat in food.

In PSC, inflammation of the bile ducts leads to scar formation and narrowing of the ducts over time. As scarring increases, the ducts become blocked. As a result, bile builds up in the liver and damages liver cells. Eventually, scar tissue can spread throughout the liver, causing cirrhosis and liver failure.