Pancreatic exocrine and endocrine responses in chronic pancreatitis.

To test the discriminatory potential of certain indices of pancreatic function we performed duodenal perfusion studies and measured trypsin, bicarbonate, and lactoferrin outputs, and plasma concentrations of pancreatic polypeptide and motilin in the basal state and during continuous intravenous stimulation with 100 ng kg-1h-1 Ceruletide and 1 CU kg-1h-1 secretin. The following groups were studied: 12 normal volunteers (NV), seven patients with chronic pancreatitis with steatorrhea (CPS), and seven without steatorrhea (CP). Stimulated trypsin outputs, after 45 min of stimulation, were the best discriminant among the groups (NV versus CPS, p less than 0.0005; NV versus CP, p less than 0.005; CP versus CPS, p less than 0.05). Basal trypsin outputs showed similar patterns but failed to discriminate between NV and CP. Bicarbonate outputs were less discriminatory than trypsin outputs. Lactoferrin outputs failed to discriminate, but transient high peak outputs occurred in the initial stimulation period in all four patients with calcific chronic pancreatitis, suggesting a washout phenomenon. Basal motilin levels were elevated in both groups of pancreatitis (p less than 0.05). Stimulated pancreatic polypeptide levels were lower in CPS (NV versus CPS, p less than 0.05) but higher in CP (NV versus CP, p less than 0.005). These differences were also apparent in the basal state. We conclude that the best discrimination among the three groups was achieved by measurement of trypsin outputs, after 45 min of stimulation. In addition, the pancreatic polypeptide response may be used as a marker of residual pancreatic function in chronic pancreatitis.