In most cases, cholangitis occurs after prolonged obstruction of the bile duct by gallstones or a bile duct tumor. Once the bile duct has become blocked, the bile duct may become infected. Cholangitis can spread from the common bile duct and into the liver.

Additional causes include:

• Parasites
• Pancreatitis
• Cholecystitis
• Surgery on the gallbladder, stomach or intestine