Choledocholithiasis refers to the presence of gallstones within the common bile duct (CBD). Stones may arise secondarily migrating from the gallbladder through the cystic duct into the CBD, accounting for the vast majority of cases or primarily within the bile duct itself, typically brown pigment stones forming as a result of biliary stasis and infection. The condition affects approximately 10–15% of patients with gallstones and carries significant clinical consequence, as even a single stone lodged in the CBD can cause complete biliary obstruction, ascending cholangitis and acute biliary pancreatitis, all potentially life-threatening complications. Unlike gallbladder stones, CBD stones rarely resolve spontaneously and require active intervention in virtually all cases once identified.
Symptoms
The clinical presentation ranges from entirely asymptomatic stones discovered incidentally during cholecystectomy to life-threatening sepsis. Symptomatic CBD stones classically produce obstructive jaundice with progressive yellowing of the sclera and skin, dark tea-coloured urine and pale, acholic stools reflecting impaired bilirubin excretion into the bowel. Right upper quadrant or epigastric biliary colic accompanies obstruction, often associated with nausea and vomiting. When biliary obstruction is complicated by bacterial infection of the bile duct, acute cholangitis develops presenting with Charcot's triad of fever with rigors, jaundice and right upper quadrant pain. The most severe form, Reynold's pentad, adds hypotension and confusion, indicating septic shock and demanding emergency biliary decompression. Acute biliary pancreatitis occurs when a stone impacts at the ampulla of Vater, obstructing pancreatic duct drainage presenting with severe epigastric pain radiating to the back and markedly elevated serum amylase.
Diagnosis
Liver function tests reveal a cholestatic pattern elevated conjugated bilirubin, markedly raised ALP and GGT, with transaminases elevated to a lesser degree. Abdominal ultrasound is the first-line investigation, demonstrating biliary ductal dilatation (CBD > 6 mm) and often visualising the stone, though sensitivity for CBD stones is limited by overlying bowel gas. MRCP (Magnetic Resonance Cholangiopancreatography) is the gold standard non-invasive investigation, providing exquisite detail of the entire biliary tree, confirming stone presence, number and location with high sensitivity and specificity. Endoscopic Ultrasound (EUS) offers comparable accuracy to MRCP and is preferred when stones are small or MRCP is inconclusive.
Treatment
ERCP (Endoscopic Retrograde Cholangiopancreatography) with sphincterotomy and stone extraction is the definitive treatment, a therapeutic endoscopic procedure in which the ampulla of Vater is incised (sphincterotomy) and stones are retrieved using a Dormia basket or balloon catheter under fluoroscopic guidance, achieving clearance in over 90% of cases. For large or impacted stones, mechanical lithotripsy or cholangioscopy-guided electrohydraulic lithotripsy is employed to fragment the stone before extraction. Following successful CBD clearance, laparoscopic cholecystectomy is performed to remove the gallbladder and eliminate the source of further stone formation. In patients presenting with acute cholangitis, emergency biliary decompression via ERCP is performed urgently alongside IV antibiotics and fluid resuscitation with cholecystectomy deferred until the acute episode resolves.