Direct Measurement of Pancreatic Enzymes After Stimulation With Secretin Versus Secretin Plus Cholecystokinin

Abstract

ABSTRACTBackground:Direct measurement of pancreatic enzymes after administration of pancreatic secretagogues is the gold standard in the assessment of exocrine pancreatic function. Recent experience at the authors' institution showed that endoscopic collection of pancreatic secretions 5, 10, and 15 minutes after intravenous administration of secretin is useful in screening for pancreatic insufficiency. Concomitant administration of intravenous cholecystokinin has been a subject of debate. The purpose of this study was to compare pancreatic enzyme levels after administration of secretin versus secretin plus cholecystokinin and to validate the timing of collection of duodenal fluid.Methods:A prospective, randomized, double‐blind study was conducted from September 1997 through September 1998. Patients scheduled for pancreatic enzyme sampling were randomly assigned to receive intravenous secretin (2 U/kg) plus placebo (group 1) or intravenous secretin (2 U/kg) plus cholecystokinin (0.02 μg/kg [Group 2]). Duodenal fluid was collected 5, 10, and 15 minutes later and placed in dry ice. Samples were measured for the levels of trypsin, amylase, lipase, and chymotrypsin.Results:Twenty patients were assigned to each group. The age range was similar in both groups: 12 months to 16 years, 8 months in group 1 (median, 2.1 years) and 15 months to 13 years, 7 months in group 2 (median, 2.5 years). Group 2 had a greater number of patients with all four enzymes at normal levels during at least one of the time points, 75% versus 50% (P = 0.102). The difference in enzyme levels at the 5‐, 10‐, and 15‐minute collections was statistically significant. For all four enzymes in both groups, values varied from highest to lowest with time (P = 0.0001). The enzyme levels at 10 minutes were close to the enzyme levels at 5 minutes; the lowest values occurred at 15 minutes.Conclusions:Higher pancreatic enzyme levels were obtained after administration of secretin plus cholecystokinin, although the trend did not reach statistical significance. Pancreatic enzyme levels are highest at 5 and 10 minutes, indicating that collections of duodenal fluid should be completed within 10 minutes of the administration of the secretagogues.