Stones (common)

Duct trauma due to surgery (common)

Tumors

Scarring due to chronic pancreatitis

External compression by a cyst, a hernia of the common bile duct (choledochocele), or a pancreatic pseudocyst (rare)

Extrahepatic or intrahepatic strictures due to primary sclerosing cholangitis

AIDS-related cholangiopathy or cholangitis

Parasitic infestation with Clonorchis sinensis or Opisthorchis viverrini

Parasite migration of Ascaris lumbricoides into the common bile duct (rare)