Pancreatic stone predominantly composed of fatty acid calcium

A 41-year-old man with chronic pancreatitis and pancreatic stones predominantly composed of fatty acid calcium is reported. He had complained of occasional abdominal pain for 10 years and visited the hospital because of a severe attack of abdominal pain. Laboratory data supported a diagnosis of pancreatitis. Computed tomography (CT) showed a high-density area in the head of the pancreas, and the CT number of this high-density area was lower than usual for pancreatic stones. Ultrasonography and endoscopic retrograde pancreatography showed a cystic lesion with small pancreatic stones in the head of the pancreas and irregular dilatation of the main pancreatic duct. Pancreaticojejunostomy and resection of pancreatic cyst were carried out for repeated episodes of abdominal pain under the diagnosis of chronic pancreatitis. The pancreatic stones obtained at surgery were proved to be mainly composed of fatty acid calcium after analysis of chemical composition of the stones. Fatty acid calcium was sometimes found in the biliary stones but never in the pancreatic stones.