Chronic calcifying pancreatitis: epidemiology and current concept of the lithogenesis.

The exact aetiology of chronic calcifying pancreatitis is unknown; several factors that lead to the development of this well-defined disease have been identified. Epidemiologic studies and careful analysis of nutritional data played an important role in precising the risk represented by alcohol consumption and dietary habits, and characterized the geographical distribution of the disease. At the same time, biochemical modifications of the pancreatic juice were described in alcoholics; later on, a new family of pancreatic secretory protein, the so-called "Pancreatic Stone Protein" was discovered. While its secretory form (PSP S2-5) prevents calcium crystal formation from the supersaturated pancreatic juice, its partially degraded form (PSP S1) is insoluble and probably the main protein of intraductal and intraacinar precipitates. Recent studies have confirmed that in chronic calcifying pancreatitis patients the mRNA encoding the synthesis of PSP S2-5 is decreased, and the protein is diminished both in the zymogen granules and in the pancreatic juice.