Choledocholithiasis: Common Bile Duct Stones – Symptoms & Treatment

What is choledocholithiasis? (Common bile duct stones)

Choledocholithiasis refers to the presence of one or more stones in the common bile duct (CBD). Most CBD stones originate in the gallbladder and migrate down the cystic duct into the common bile duct. Less commonly, stones form primarily in the CBD (primary choledocholithiasis), usually in patients with bile stasis or recurrent infections. CBD stones are dangerous because they can obstruct bile flow, leading to jaundice, cholangitis (bile duct infection), and pancreatitis. They require prompt diagnosis and removal, typically by ERCP.

Symptoms – jaundice, dark urine, pale stools, pain, fever

Symptoms depend on the degree of obstruction and presence of infection:

• Obstructive jaundice: Yellowing of the skin and eyes, dark urine (bilirubin), pale or clay‑coloured stools. Usually the first sign.
• Right upper quadrant or epigastric pain: May be constant or colicky, often less severe than biliary colic.
• Fever and chills: Suggest ascending cholangitis – a medical emergency.
• Nausea and vomiting.
• Pruritus (itching): Due to bile salts deposited in the skin.
• Gallstone pancreatitis: If the stone impacts the ampulla of Vater, causing severe epigastric pain radiating to the back, elevated lipase.

Causes – migrating gallstones, primary CBD stones

• Secondary choledocholithiasis (90‑95%): Stones migrate from the gallbladder into the CBD. Risk factors: small stones (<5mm), multiple stones, dilated cystic duct.
• Primary choledocholithiasis (5‑10%): Stones form directly in the CBD. Associated with bile stasis (strictures, choledochal cysts, Caroli disease), recurrent infections (brown pigment stones), or parasitic infections (Clonorchis sinensis, Ascaris).
• Recurrent CBD stones after cholecystectomy: Can occur in 5‑10% of patients, especially with bile duct strictures or sphincter of Oddi dysfunction.

Diagnosis – LFTs, ultrasound, MRCP, EUS, ERCP

Diagnosis is confirmed with imaging and blood tests:

• Liver function tests (LFTs): Elevated alkaline phosphatase (ALP), GGT, and direct bilirubin. ALT/AST may be mildly elevated.
• Transabdominal ultrasound: May show a dilated common bile duct (>6‑8mm) and occasionally stones (sensitivity 20‑30%). Also evaluates the gallbladder.
• Magnetic resonance cholangiopancreatography (MRCP): Non‑invasive, highly sensitive (90‑95%) for CBD stones. Preferred initial imaging if suspicion is moderate to high.
• Endoscopic ultrasound (EUS): Very sensitive (95‑98%), especially for small stones (<5mm). Can be followed immediately by ERCP.
• ERCP (endoscopic retrograde cholangiopancreatography): Gold standard – both diagnostic and therapeutic. Direct visualisation and stone extraction.

Treatment – ERCP with sphincterotomy and stone extraction

ERCP is the primary treatment for CBD stones. Steps:

1. Sedation or general anaesthesia.
2. Duodenoscope passed to the ampulla of Vater.
3. Cannulation of the bile duct.
4. Cholangiogram to confirm stone location, size, and number.
5. Sphincterotomy (cutting the muscle) to enlarge the opening.
6. Stone extraction using a balloon or basket.
7. For large stones (>15‑20mm), mechanical lithotripsy or laser lithotripsy may be needed.
8. Balloon sweep to confirm clearance.
9. If stones cannot be removed, temporary plastic stent placement (to prevent cholangitis) with repeat ERCP after 4‑6 weeks.

Success rate: 90‑95% for stones <15mm. After ERCP, patients with an intact gallbladder require cholecystectomy (unless high surgical risk) to prevent recurrent CBD stones (30‑50% risk within 5 years).

Complications – cholangitis, pancreatitis, secondary biliary cirrhosis

Untreated or recurrent CBD stones can lead to:

• Ascending cholangitis: Bacterial infection of the bile duct. Charcot’s triad (fever, jaundice, RUQ pain) progresses to Reynolds’ pentad (plus hypotension and altered mental status). Mortality 10‑30% if untreated.
• Acute pancreatitis: Stone impacted at the ampulla causes pancreatic enzyme activation. Severe pancreatitis has 10‑20% mortality.
• Secondary biliary cirrhosis: Long‑term obstruction leads to liver fibrosis and cirrhosis.
• Recurrent pyogenic cholangitis (Oriental cholangiohepatitis): Repeated infections cause intrahepatic stones and strictures.

Prevention – cholecystectomy after ERCP

After successful ERCP and removal of CBD stones, the gallbladder remains a source of stones. Without cholecystectomy, 30‑50% of patients will develop recurrent CBD stones within 5 years. Therefore:

• Cholecystectomy is recommended for fit patients – typically performed 2‑6 weeks after ERCP (or during the same admission).
• High‑risk surgical patients (severe cardiac/pulmonary disease, cirrhosis) may be managed with observation and repeat ERCP if stones recur.

Interactive FAQ – Choledocholithiasis

Disclaimer: This information is for educational purposes. If you have jaundice, dark urine, or abdominal pain, seek immediate medical attention at Vivekananda Hospital.