Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is a chronic fibro-inflammatory disease of the bile ducts. Immune-mediated injury is suspected, although the precise cause remains unknown. Inflammation and fibrosis create multiple areas of narrowing in the intrahepatic and extrahepatic ducts. On imaging, these alternating narrowed and dilated segments create a beaded appearance. The ducts are the liver’s drainage channels for bile. As strictures tighten, bile flow slows and backs up, producing cholestasis. This explains the typical biochemical pattern of elevated alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT), as well as symptoms such as pruritus, fatigue, and jaundice. Persistent obstruction damages liver tissue over time, leading to biliary cirrhosis, portal hypertension, and liver failure. Stagnant bile above a stricture also creates conditions for bacterial infection. A previously stable person with PSC who develops fever, chills, new abdominal pain, or worsening jaundice may have acute cholangitis rather than simply “progressing PSC.” That shift in presentation changes the priority from chronic disease monitoring to emergency assessment, antibiotics, and biliary drainage. PSC is strongly associated with inflammatory bowel disease (IBD), particularly ulcerative colitis. The bowel disease may...