There are many causes of acute severe pancreatitis, and the mechanisms of onset are not completely the same.

Biliary pancreatitis is caused by small gallstones falling into the bile duct, becoming lodged at the distal end of the duct. At this time, the opening of the pancreatic duct is blocked, causing a disorder in pancreatic juice secretion, increasing pancreatic duct pressure, and spilling out of the pancreatic duct. This can corrode pancreatic cells and other abdominal organ cells.

Alcohol and drug-induced pancreatitis is due to the direct damage of alcohol and drugs to the pancreatic cells, causing the leakage of pancreatic secretions.

Overeating-induced pancreatitis is caused by consuming too much food at once, especially a high-fat diet, leading to a massive secretion of pancreatic juice. If there is an obstacle in the expulsion of this juice, it can also lead to pancreatitis.

Hyperlipidemic pancreatitis is caused by excessively high blood lipid levels, which form blockages. These lipids obstruct the secretion of the pancreatic duct, causing pancreatitis.

In all types of pancreatitis, the leakage of pancreatic secretions corrodes the pancreatic cells and these secretions enter the abdominal cavity, corroding abdominal organs and leading to a series of severe inflammatory responses and potentially leading to abdominal infections.