Proteases in the evaluation of pancreatic function and pancreatic disease

This paper reviews the role of pancreatic proteases (focusing upon trypsin, chymotrypsin and elastase) in the diagnosis and management of chronic pancreatic insufficiency (CPI), emphasizing advances over the last 5 years. Some important novel aspects of these enzymes in acute pancreatitis are also described, including their role in diagnosis and their interaction with cholecystokinin in the pathogenesis of the disease. The recent interest in these enzymes as agents promoting the spread of cancer in animals and human subjects is also described. A hierarchical approach has been taken to explore the advantages and limitations of tests in different source materials: serum, feces, duodenal aspirate, and non-invasive pancreatic function tests. The practical usefulness of fecal elastase-1 and of fecal chymotrypsin concentrations in diagnosis and management of CPI, respectively, is one of the major lessons to be learned from analysis of the recent literature, and forms the principal message of this review.