Serum immunoreactive trypsin and trypsin inhibitors during acute pancreatitis.

Serum trypsin, total trypsin-inhibitor capacity, alpha-1-antitrypsin and alpha-2-macroglobulin were analyzed daily in ten patients hospitalized as a result of acute pancreatitis. Markedly raised serum trypsin concentrations were found in all patients. Alpha-1-antitrypsin and the trypsin-inhibitor capacity were also significantly increased as compared to post-illness values, but alpha-2-macroglobulin tended to decrease during acute pancreatitis. The post-illness values of all these parameters were in the normal range. It is concluded that a deficiency of alpha-1-antitrypsin, trypsin-inhibitor capacity of alpha-2-macroglobulin is not present in patients with acute pancreatitis which could render the pancreas more vulnerable to its own proteases. During acute pancreatitis trypsin is released into the circulation, but it is effectively inactivated by serum protease inhibitors, mainly alpha-1-antitrypsin, which can be seen as an increased trypsin-inhibitor capacity in these patients. The use of protease inhibitors in the treatment of acute pancreatitis seems to be unnecessary against this background. Increased serum trypsin values can be used when confirming the diagnosis of acute pancreatitis.