The ratio of trypsin-2-alpha(1)-antitrypsin to trypsinogen-1 discriminatesbiliary and alcohol-induced acute pancreatitis

Background: Rapid determination of the etiology of acute pancreatitis (AP) enables institution of appropriate treatment. We evaluated the ability of t rypsinogen-1, trypsinogen-2, trypsin-1-alpha (1)-antitrypsin (AAT), and try psin-2-AAT in serum to identify the etiology of AP. Methods: The study consisted of 67 consecutive patients with AP admitted to Helsinki University Central Hospital. Forty-two had alcohol-induced AP, 16 had biliary AP, and 9 had unexplained etiology. Serum samples were drawn w ithin 12 h after admission. Trypsinogen-1, trypsinogen-2, trypsin-1-AAT, an d trypsin-2-AAT were determined by time-resolved immunofluorometric assays. Logistic regression was used to estimate the ability of the serum analytes to discriminate between alcohol-induced and biliary AP. The validity of th e tests was evaluated by ROC curve analysis. Results: Patients with alcohol-induced AP had higher median values of tryps in-1-AAT (P = 0.065), trypsinogen-2 (P = 0.034), and trypsin-2-AAT (P < 0.0 01) than those with biliary AP, who had higher values of amylase (P = 0.002 ), lipase (P = 0.012), and alanine aminotransferase (P = 0.036). The ratios of trypsin-2-AAT to trypsinogen-1, lipase, or amylase efficiently discrimi nated between biliary and alcohol-induced AP (areas under ROC curves, 0.92- 0.96). Conclusions: Trypsinogen-2 and trypsin-2-AAT are markedly increased in AP o f all etiologies, whereas trypsinogen-1 is increased preferentially in bili ary AP. The trypsin-2-AAT/trypsinogen-1 ratio is a promising new marker for discrimination between biliary and alcohol-induced AP. (C) 2001 American A ssociation for Clinical Chemistry.