What is the most common cause of pancreatitis?

Most Common Causes of Pancreatitis

Gallstones and alcohol consumption are the most common causes of pancreatitis, accounting for 60-75% of all cases. 1, 2

Primary Etiologies

• Gallstones (biliary pancreatitis) - The leading cause of acute pancreatitis in many countries and regions 1, 3
• Alcohol consumption - The second most common cause overall, with incidence varying by region and associated with high alcohol intake 1, 3

Epidemiology and Risk Distribution

• The proportion of gallstone versus alcoholic pancreatitis varies significantly by geographic region 3
• Alcoholic pancreatitis has a higher incidence in men, though the risk is similar between sexes when adjusted for alcohol intake 3
• In chronic pancreatitis, alcohol is the etiological factor in 60-70% of cases 1

Other Important Causes

• Drug-induced pancreatitis - Particularly from medications such as:

  • Azathioprine/6-mercaptopurine (occurs in approximately 4% of treated IBD patients) 1
  • 5-ASA compounds (lower risk than thiopurines) 1

• Post-ERCP (Endoscopic Retrograde Cholangiopancreatography) - A significant iatrogenic cause 1, 3

• Metabolic causes (accounting for 5-10% of cases):

  • Hypertriglyceridemia 4
  • Hypercalcemia 4
  • Diabetes mellitus 4

• Other etiologies:

  • Abdominal trauma 2
  • Infections 2
  • Autoimmune pancreatitis 1
  • Pancreatic duct abnormalities (obstruction, pancreas divisum) 1
  • Hereditary or tropical pancreatitis 1

• Idiopathic pancreatitis - Accounts for approximately 15% of cases where no specific cause can be identified 4

  • Some cases of idiopathic pancreatitis may be due to microlithiasis (sludge) 3, 5

Clinical Implications

• Severe necrotizing pancreatitis develops in 10-20% of patients with mortality rates of 14-25% 3
• Recurrence rates are high:
  • Almost half of patients with alcoholic pancreatitis experience recurrence 3
  • 32-61% recurrence in untreated gallstone pancreatitis 3
  • Identifying and treating the underlying cause is crucial for preventing recurrent episodes 4

Diagnostic Considerations

• Diagnosis requires a combination of clinical history, physical examination, laboratory tests, and imaging 2
• CT and MRI have limited roles in diagnosing biliary sludge but may show papillitis suggesting small stones or recently passed stones 5
• Endoscopic ultrasonography is considered the most accurate test for detecting sludge 5

Management Approach

• Treatment should address both the acute inflammatory process and the underlying cause 2
• Early laparoscopic cholecystectomy is indicated for mild gallstone pancreatitis 2
• Abstinence from alcohol is essential for patients with alcoholic pancreatitis 1
• Metabolic causes require specific management of the underlying metabolic abnormality 4