Different patterns in immunoreactive anionic and cationic trypsinogen in urine and serum in human acute pancreatitis

Background: Acute pancreatitis (AP) results in elevated concentrations of t rypsinogen (T) isoenzymes in serum. Immunoreactive anionic trypsinogen in u rin (irAT/u) is elevated in AP, and has recently been proposed as a rapid d iagnostic instrument and severity predictor. These results have not been co nfirmed by other groups, and irAT/u has not been further characterized. The concentration of immunoreactive cationic trypsinogen in urine (irCT/u) and the serum irAT/irCT ratio in AP have not been extensively examined. Methods: Levels of irAT and irCT were studied in urine and serum from 50 AP patients and in urine from 41 non-AP patients. Severity was assessed accor ding to the Atlanta classification. irAT/u was characterized by gel filtrat ion. Results: Gel filtration revealed only AT in the mine. Highly significant di fferences in irAT/u were seen between AP/non-AP (p < 0.0001) and mild/sever e disease (p = 0.0012). The irAT/irCT ratio in serum changed from normal 0. 8 to 1.3 in AP. Conclusions: IrAT and only traces of irCT were found in the urine in AP. Ir AT/u was higher in Ar than in other acute abdominal disorders (non-AP) and also higher in severe than in mild AP. IrAT in serum (irAT/s) increased pro portionally more than irCT/s in AP, but did not discriminate mild from seve re forms. High levels of irAT/u in some non-AP cases and a wide range in AP cases make the clinical value of the test questionable.