Serum Phospholipase A2, Immunoreactive Trypsin, and Trypsin Inhibitors During Human Acute Pancreatitis

Abstract

Serum immunoreactive trypsin and phospholipase A₂ were analyzed at regular intervals in seven patients hospitalized as a result of acute hemorrhagic pancreatitis. α₁-Antitrypsin and α₂-macroglobulin levels and trypsin-inhibitor capacity of serum were determined simultaneously. Serum trypsin concentrations were markedly raised in all patients. The levels of immunoreactive trypsin remained elevated for longer periods than those of urinary amylase. α₁-Antitrypsin and trypsin-inhibitor capacity were also significantly increased as compared with the post-illness values, but α₂-macroglobulin decreased considerably, reaching the lowest levels on the 5th day after admission. Consequently, phospholipase and trypsin are released to the circulation during hemorrhagic pancreatitis, but the increase in trypsin is compensated for by an increase in trypsin-inhibitor capacity of serum due to elevated α₁-antitrypsin levels. The decrease of α₂-macroglobulin in hemorrhagic pancreatitis was one of the most interesting findings, and it is proposed that this inhibitor may be consumed in the elimination of proteases through the reticuloendothelial system. The two patients who died had higher phospholipase values than those who recovered, but the prognosis could not be predicted from the values of the other measured variables.