Histochemical studies of pancreatic calculi.

Fourteen pancreatic calculi from the corresponding number of pancreatic lithiasis patients were examined mineralogically and histochemically. The following results were obtained. The main components of calculi were calcium carbonate in 13 of the 14 cases, and calcium phosphate in the remaining one. Calcium carbonate calculi were all so-called intraductal calculi, with acidic glycoprotein apparently enwrapping the component particles. Acidic glycoproteins acted to bridge calcium carbonate particles, as in the cases of gallstone and urinary stone. The calcium phosphate calculus had a histochemical feature of pathologic calcification with degenerated collagen fibrils as the matrix, suggesting the calcification of the fibrotic pancreatic parenchyma after pancreatitis.