Pancreatitis literally means inflammation of the pancreas. If the condition is sudden in onset it is called acute pancreatitis, whereas chronic pancreatitis is a continuing inflammatory process with sub-acute recurrence's of the disease. Both forms of the disease can lead to permanent damage and reduced functionality of the pancreas with serious consequences for the animal. When the pancreas is inflamed local release of enzymes occurs including trypsin, kallikrein, elastase, lipase, phospholipase A, amylase and lysosymes. These cause local problems in adjacent tissues and affect the range of clinical signs that develop including causing peritonitis.
Full information can be found at this link Pet Education - Pancreatitis.