The most appropriate management is to perform cholecystectomy for gallstone-induced acute pancreatitis prior to hospital discharge. In the United States, 80% of cases of acute pancreatitis are caused by gallstones or alcohol use. The pathophysiology of gallstone-induced pancreatitis is likely related to gallstone obstruction of the common channel (bile-pancreatic duct) or reflux of bile into the pancreatic duct owing to impaction of the stone at the ampulla. Elevation of the alanine aminotransferase concentration is the most clinically useful laboratory test predicting gallstone pancreatitis. In addition, this patient has evidence of gallstones on ultrasonography. Patients with gallstone pancreatitis and no complications should have a cholecystectomy prior to discharge to prevent recurrent attacks. Delaying cholecystectomy is warranted to reduce the risk of sepsis and complications in patients with severe acute pancreatitis, particularly with pancreatic necrosis and acute peripancreatic fluid collections.

Cholecystokinin hepatobiliary (CCK-HIDA) scintigraphy is most commonly used for evaluation of cholecystitis, biliary obstruction, and suspected gallbladder dysfunction. This is not appropriate for this patient because he has no ultrasound evidence of cholecystitis.

Endoscopic retrograde cholangiopancreatography (ERCP) and biliary sphincterotomy are not indicated in the absence of cholangitis or nonresolving biliary obstruction unless the patient is not a surgical candidate for cholecystectomy. Obstruction is typically indicated by a dilated bile duct and persistently elevated liver enzyme levels.

Antibiotics should be reserved for treatment of cholangitis, acute cholecystitis, or other infections, which are absent in this patient. Cholangitis typically presents with fever, jaundice, and pain in the right upper quadrant (Charcot triad). Most patients will have cholelithiasis, elevated aminotransferase levels, and hyperbilirubinemia. Ultrasonography may show a dilated common bile duct. Findings of cholecystitis may include thickening of the gallbladder wall (>2 mm), intramural gas, and pericholecystic fluid. Hepatobiliary scintigraphy is indicated to confirm or exclude the diagnosis of acute cholecystitis when the initial ultrasound is indeterminate.