What is the risk of pancreatitis in patients with uncomplicated cholelithiasis (gallstones)?

Risk of Pancreatitis in Uncomplicated Cholelithiasis

Patients with uncomplicated cholelithiasis have approximately an 11-15% risk of developing pancreatitis, with small gallstones (less than 5mm) increasing this risk by more than 4-fold. 1, 2

Risk Factors for Pancreatitis in Gallstone Disease

• Small gallstone size (less than 5mm in diameter) is the strongest independent risk factor for developing acute biliary pancreatitis, with a 4.5-fold increased risk compared to patients with larger stones 1, 2
• Multiple gallstones (20 or more) increase the risk of pancreatitis 1
• Mulberry-shaped gallstones are associated with a 2.25-fold increased risk of pancreatitis 1
• Lower total gallstone weight is associated with higher pancreatitis risk 1

Incidence of Common Bile Duct Stones and Pancreatitis

• The prevalence of common bile duct stones (CBDS) in patients with symptomatic gallstones is between 10-20% 3
• In patients with no clinical suspicion of ductal stones prior to surgery, the incidence is lower at approximately 5% 3
• The rate of choledocholithiasis is similar between patients with mild acute biliary pancreatitis (11.4%) and those with symptomatic cholelithiasis (11.6%) 4
• Intraoperative cholangiography identifies unsuspected choledocholithiasis in approximately 6.8% of patients with mild acute biliary pancreatitis 4

Natural History and Complications

• Complications of common bile duct stones are potentially life-threatening and include:

  • Acute pancreatitis
  • Obstructive jaundice
  • Cholangitis
  • Hepatic abscesses
  • Secondary biliary cirrhosis 3

• In the GallRiks study, 25.3% of patients with CBDS left in situ experienced unfavorable outcomes (defined as pancreatitis, cholangitis, bile duct obstruction, or subsequent symptoms with proven CBDS) over a follow-up period of 0-4 years 3

• Only 12.7% of patients who underwent stone extraction experienced unfavorable outcomes (OR 0.44,95% CI 0.35-0.55) 3

• Even for small stones (<4mm), active treatment reduced unfavorable outcomes from 15.9% to 8.9% (OR 0.52,95% CI 0.34-0.79) 3

Prevention of Pancreatitis

• Cholecystectomy for cholelithiasis is associated with a reduced risk of pancreatitis (adjusted HR 0.49; 95% CI 0.36-0.68) in patients without a previous history of pancreatitis 5
• The risk reduction is most significant in patients younger than 50 and older than 65 years 5
• Both men and women exhibit reduced risks of pancreatitis after cholecystectomy 5

Risk Stratification for Common Bile Duct Stones

• Patients with gallstones should be risk-stratified for CBDS according to the following criteria:

  • High risk: Evidence of CBDS on ultrasound or ascending cholangitis
  • Moderate risk: Common bile duct diameter >6mm, total bilirubin >1.8mg/dl, abnormal liver biochemical tests, age >55 years, or clinical gallstone pancreatitis
  • Low risk: No predictors present 3

• Patients with moderate risk should undergo further evaluation with MRCP, EUS, intraoperative cholangiography, or laparoscopic ultrasound 3

• Patients with high risk should undergo preoperative ERCP, intraoperative cholangiography, or laparoscopic ultrasound 3

Management Considerations

• Patients with CBDS should be offered stone extraction if possible, with the strongest evidence of benefit for symptomatic patients 3
• Asymptomatic CBDS are associated with increased incidence of post-ERCP pancreatitis compared to symptomatic CBDS 6
• A policy of watchful waiting is unwarranted in patients with small gallstones (<5mm) due to the significantly increased risk of pancreatitis 1, 2