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 trypsinogen (T) isoenzymes in serum. Immunoreactive anionic trypsinogen in urin (irAT/u) is elevated in AP, and has recently been proposed as a rapid diagnostic instrument and severity predictor. These results have not been confirmed 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 according to the Atlanta classification. irAT/u was characterized by gel filtration.

RESULTS

Gel filtration revealed only AT in the urine. Highly significant differences in irAT/u were seen between AP/non-AP (p < 0.0001) and mild/severe 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. IrAT/u was higher in AP than in other acute abdominal disorders (non-AP) and also higher in severe than in mild AP. IrAT in serum (irAT/s) increased proportionally more than irCT/s in AP, but did not discriminate mild from severe 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.