Does edematous pancreatitis exist in biliary-related pancreatitis? A hemodynamic and histologic study of the progression of bile-induced pancreatitis.

The progression of pancreatitis induced in dogs by either single or hourly injections of two different bile solutions was monitored to determine whether acute necrotizing pancreatitis developed through an earlier mild interstitial form. In this model of biliary-related pancreatitis, acute interstitial pancreatitis could not be produced. The earliest lesion produced, although having the macroscopic appearance of edematous pancreatitis, was histologically a mild necrotizing form of the disease. If the bile solution was of sufficient concentration, then further injections resulted in progression of the pancreatitis from this mild form of scattered areas of focal acinar necrosis through coalescence of these areas to areas of parenchymal hemorrhage. Pancreatic blood flow, measured through its arterial inflow, increased during the earliest phase of the disease, but then decreased as the disease progressed.