What Is It?
Your gallbladder stores bile until you eat, then releases bile into your small intestine to help digest food. Bile ducts are small drainage "pipes" that carry bile (a mix of cholesterol, acids, salts and waste products) from the liver to the gallbladder and from the gallbladder to the small intestine. A variety of diseases can affect your bile ducts. All block the bile ducts in some way, which is why the various diseases cause similar symptoms.
Gallstones are the most common cause of blocked bile ducts. Stones typically form inside the gallbladder and can block the common bile duct, a large drainpipe at the base of the liver. If the duct remains blocked, waste can collect in the bile duct system and in the bloodstream. Also, if bacteria above the blockage accumulates and backs up into the liver, it may cause a severe infection called ascending cholangitis. If a gallstone stops in between the gallbladder and the common bile duct, an infection called cholecystitis can occur.
Less common causes of blockages include cancers of the bile duct (cholangiocarcinomas) and strictures (scars that narrow the ducts after infection, surgery or inflammation).
Other bile duct diseases are uncommon, and include primary sclerosing cholangitis and primary biliary cirrhosis. Typically diagnosed in mid-adulthood, these conditions create ongoing inflammation in the bile duct walls, which can narrow and scar the walls. These conditions have an inherited (genetic) component, although other factors seem necessary to trigger the disease. Primary sclerosing cholangitis is more common in men, and 75% of the time it is seen in people with inflammatory bowel disease (ulcerative colitis or Crohn's disease). Primary biliary cirrhosis is more common in women, and is sometimes associated with autoimmune diseases such as Sjogren's syndrome, thyroiditis, scleroderma or rheumatoid arthritis.
Biliary atresia is a rare form of bile duct blockage that occurs in some infants two weeks to six weeks after birth, a time when the bile ducts have not completed their development normally.