A 50-year-old chronic alcoholic presents to the emergency room with 12 hours of severe abdominal pain. The pain radiates to the back and is associated with an urge to vomit. Physical examination discloses exquisite abdominal tenderness. Laboratory studies show elevated serum amylase. Which of the following morphologic changes would be expected in the peripancreatic tissue of this patient?

Fat necrosis. Saponification of fat derived from peripancreatic fat cells exposed to pancreatic enzymes is a typical feature of fat necrosis. Lipase, released from pancreatic acinar cells during an attack of acute pancreatitis, hydrolyzes fat into fatty acids and glycerol. Free fatty acids bind with calcium to form soaps, which is a process known as saponification. Entry of calcium ions into the injured tissue reduces the level of calcium in blood. Hypocalcemia is, therefore, a typical finding in patients who had a recent bout of acute pancreatitis. Patients with acute pancreatitis experience sudden-onset abdominal pain, distention, and vomiting. The other choices are not typically seen in peripancreatic tissue following acute pancreatitis, although liquefactive necrosis (choice E) may be observed.Diagnosis: Acute pancreatitis