Abstract
In this necropsy review of 37 cases of acute pancreatitis, evidence is presented that there are at least two different initiating mechanisms in acute necrotising pancreatitis in man. Firstly, there is primary duct inflammation, with subsequent inflammation and necrosis of the pancreatic parenchyma surrounding the excretory ducts. Included in this group are cases secondary to alcohol abuse and cholelithiasis. Secondly, there is necrosis confined to the microcirculatory periphery of the pancreatic lobule. These cases are usually secondary to some form of shock (septic or cardiogenic) and are thought to represent ischaemic pancreatitis. These patterns of necrosis are discussed in relation to the pancreatic anatomy and clinical findings.