P amylase is always greater than S in spot urine of normal subjects. Diagnostic implications

Single random samples of urine were collected from 50 control subjects; 27 patients with chronic pancreatitis; 19 with acute pancreatitis; 6 with acute on chronic pancreatitis; five in the recovery phase of acute attack; four patients with pseudocysts. Salivary (S) and pancreatic (P) amylase values were measured by cellulose acetate electrophoresis. The P amylase values always exceeded those of S amylase in the control specimens. In acute pancreatitis, both the lower and upper levels of total and P amylase were considerably higher than in the controls, and these high values tended to return to normal during the recovery phase of acute pancreatitis. The S amylase values were often very low or undetectable during the acute phase. Values for P amylase exceeded control values in patients with pseudocysts even in the presence of chronic pancreatitis. In chronic calcific pancreatitis, S amylase was higher than P amylase. We conclude that P amylase is always greater than S amylase in normal urine specimens, and a change in this pattern may be helpful in diagnosing various forms of pancreatitis.