Sepsis is the most common cause of late death in pancreatitis. The presence of early bacterial infection has been correlated with the severity of the disease. A choline-deficient ethionine-supplemented (CDE) diet given to young female mice produces severe necrotizing pancreatitis that has morphologic and biochemical similarities to the human disease. We therefore searched for bacterial pancreatic infection in female CD-1 mice given the CDE diet. The mortality rate was 47.5% in mice fed the CDE diet. All of these mice had severe pancreatitis with inflammation, edema, and necrosis on histologic examination. Bacterial infection was present in 1/12 pancreatica among nonsurvivors and in 1/32 pancreatica in surviving animals (p not significant). Histologic examination showed edema to be more pronounced in surviving mice, although the overall severity of morphologic changes was not significantly different between survivors and nonsurvivors. We conclude that bacterial infection is not a determinant of the severity or lethality of experimental pancreatitis induced by the CDE diet.