Elevated pancreatic secretory trypsin inhibitor levels during severe inflammatory disease, renal insufficiency, and after various surgical procedures.

Elevated levels of immunoreactive pancreatic secretory trypsin inhibitor (PSTI) were found in serum from patients with perforated duodenal ulcer, bacterial peritonitis, urosepticemia, pneumonia, acute renal failure, and also after different surgical procedures. The extent of the trauma seemed to determine the maximal level of PSTI. The increase found paralleled the changes seen in the acute-phase protein antichymotrypsin. There was, however, almost no increase in trypsinogen, thought to be produced together with PSTI in the acinar cells of the pancreas. In conclusion, there is evidence that PSTI is probably also produced somewhere outside the pancreas, in agreement with recent immunohistochemical data. This production may be part of a general acute-phase reaction. Thus, PSTI may have a more general inhibitory function against trypsin-like protease release in tissue injury, instead of being a purely local trypsin inhibitor in the pancreatic gland.