The bile ducts are responsible for emptying the liver of bile, a substance used in the process of digestion. Problems that occur in these ducts can originate in the gallbladder, pancreas or adjacent digestive organ. Most cause some level of obstruction in the normal flow of bile, which results in infection, inflammation or internal scarring.
Gallstones are small, pebble-like substances that form in bile. Bile is composed of several substances, including water, salts, fats, proteins and bilirubin (a breakdown of red blood cells). Gallstones fall into two categories: cholesterol and pigment. Cholesterol gallstones are composed of hardened fats and account for around 80 percent of all gallstones. Pigment gallstones are composed of hardened bilirubin. Gallstones typically range from the size of a grain of rice to the size of a golf ball and cause pain by obstructing the normal flow of bile through the digestive tract.
Biliary atresia is a rare form of disease that affects an average of 1 in every 10,000 infants. It affects the victim by injuring or killing the ducts responsible for removing bile from the liver. As bile builds in the liver, it causes internal scarring and loss of liver tissue. Over time, this can lead to cirrhosis (the replacement of liver tissue by scar tissue or nodules) and the need for liver transplant. In fact, biliary atresia is currently the primary cause of liver transplants in the United States.
Cholecystitis is characterized by an inflammation of the gallbladder and nearby abdominal lining. It occurs typically as a result of gallstones. It can lead to severe infection of the bile ducts as well as pancreatic tumors and a decrease in blood flow to the gallbladder. Other symptoms include abdominal pain, nausea, vomiting, chills, fever, bloating, loose bowel movements and jaundice (a yellowing of the skin, mucous membranes or eyes).
Cholangiocarcinoma is cancer of the bile ducts. It results in a malignant transformation of the bile ducts, leading to jaundice, anorexia, weight loss and fatigue. It is an extremely dangerous condition that requires surgical resection, radiation, chemotherapy or stinting to treat. Liver transplants are not typically prescribed for cholangiocarcinoma because of the high rate of recurrence following surgery.
Tumors of the gallbladder directly affect the bile ducts. Malignant tumors, such as those caused by adenocarcinoma, and benign tumors, such as papillomas, cause obstruction of the biliary tract and impede the movement of bile through the digestive system. This typically results in symptoms similar to gallstones, such as abdominal pain and fever. These tumors can usually be discovered through the use of radiologic tests such as CT scans.