The credit for this CME activity is available through April 30, 2013.

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Risk Factors

The two most common and important risk factors for acute pancreatitis are gallstones and alcohol consumption.¹⁰ In developed countries, the cause of acute pancreatitis is biliary in 38% of cases and alcohol abuse in 36%.^2,8,9 Gallstone pancreatitis is most likely to develop in patients older than 60 years and with small gallstones (less than 5 mm or microlithiasis).^4,10 Only 3.4% of patients with cholelithiasis develop pancreatitis.¹⁰

Alcohol is a dose-dependent risk factor after the threshold of 4-5 drinks daily is exceeded. Even among patients with the highest alcohol intake, the risk is only 2%-3%.^6,10 Smoking is another important risk factor for pancreatitis, and its effects are additive with alcohol.^3,6 Patients with HIV are 35-800 times more likely to develop acute pancreatitis when compared to a population without HIV.¹⁰

Signs and Symptoms

Patients typically present with the rapid onset of unremitting, severe epigastric pain that radiates to the back. Epigastric abdominal pain is present in 95% of these patients.¹² The classically taught Cullen (periumbilical ecchymosis) and Gray-Turner (flank ecchymosis) signs are present in only 3% of patients but have been associated with a mortality of 37%.⁸ Nausea or vomiting is present in 90% of patients.⁸

Diagnostic Tests

The American College of Gastroenterology guidelines state that two of these three findings should be present for the diagnosis of acute pancreatitis: 1) elevated serum lipase or amylase greater than or equal to three times the upper limit; 2) characteristic abdominal pain; 3) computed tomography (CT) evidence of acute pancreatitis.^1,11

The two main enzymes that aid in laboratory diagnosis of acute pancreatitis are amylase and lipase. Amylase rises within 6-24 hours and normalizes in 3-7 days.¹³ Lipase rises within 4-8 hours and stays elevated for 8-14 days.¹³ There are many advantages of lipase over amylase. Lipase remains elevated longer and is at least as sensitive and more specific than amylase.^14-16 Lipase levels of greater than five times the upper limit of normal have 100% specificity for the diagnosis of acute pancreatitis.¹³

Traditionally, amylase was recommended as the diagnostic test of choice because it was cheaper and more widely available than lipase.¹⁵ Given recent developments that have made lipase widely available and its superior test characteristics, lipase is now the laboratory measurement of choice for the diagnosis of acute pancreatitis, and there is little additional benefit from also obtaining a serum amylase level.^14,15