Which histologic changes are typical of acute pancreatitis?

Which histologic changes are typical of acute pancreatitis?

• A. Fibrosis and calcifications
• B. Edema with neutrophilic infiltration only
• C. Pancreatic fat necrosis with enzymatic fat necrosis in peripancreatic tissue, edema, and leukocyte infiltration
• D. Chronic granulomatous inflammation

Answer: (C)

In acute pancreatitis the pancreas and surrounding fat are damaged by pancreatic enzymes that leak from inflamed tissue. The hallmark histologic change is enzymatic fat necrosis in peripancreatic fat, where lipase liberates fatty acids from adipocytes. These fatty acids bind calcium to form chalky calcium soaps, a feature known as fat necrosis. Along with this fat destruction, there is tissue edema from increased vascular permeability and an inflammatory response with leukocyte (neutrophil) infiltration. This combination—fat necrosis in peripancreatic tissue, edema, and leukocyte influx—best captures the characteristic microscopic pattern of acute pancreatitis. Fibrosis and calcifications are more typical of chronic pancreatitis and long-standing injury, not the acute process. Edema with neutrophils alone misses the defining fat necrosis and enzymatic tissue destruction that differentiate acute pancreatitis histology. Chronic granulomatous inflammation is not a feature of acute pancreatitis.

In acute pancreatitis the pancreas and surrounding fat are damaged by pancreatic enzymes that leak from inflamed tissue. The hallmark histologic change is enzymatic fat necrosis in peripancreatic fat, where lipase liberates fatty acids from adipocytes. These fatty acids bind calcium to form chalky calcium soaps, a feature known as fat necrosis. Along with this fat destruction, there is tissue edema from increased vascular permeability and an inflammatory response with leukocyte (neutrophil) infiltration. This combination—fat necrosis in peripancreatic tissue, edema, and leukocyte influx—best captures the characteristic microscopic pattern of acute pancreatitis.

Fibrosis and calcifications are more typical of chronic pancreatitis and long-standing injury, not the acute process. Edema with neutrophils alone misses the defining fat necrosis and enzymatic tissue destruction that differentiate acute pancreatitis histology. Chronic granulomatous inflammation is not a feature of acute pancreatitis.