What condition is defined by obstruction of the common bile duct by gallstones?

• A. Cholangitis
• B. Cholecystitis
• C. Choledocholithiasis
• D. Pancreatitis

Answer: (C)

Choledocholithiasis is the obstruction of the common bile duct by gallstones. The common bile duct carries bile from the liver to the duodenum, and when a stone lodges there, bile flow is blocked, causing a cholestatic presentation with jaundice, dark urine, pale stools, and right upper-quadrant pain. The term combines choledocho (common bile duct) and lithiasis (stone), clearly identifying the location and cause. This condition can lead to complications such as cholangitis (infection of the bile ducts) or pancreatitis if the obstruction affects the pancreatic duct or becomes infected. Other options describe different biliary problems: cholangitis is an infection of the ducts, cholecystitis is inflammation of the gallbladder, and pancreatitis is inflammation of the pancreas, not the result of a stone in the CBD itself.