A single-specimen fecal chymotrypsin test in the diagnosis of pancreatic insufficiency: correlation with secretin-cholecystokinin and NBT-PABA tests.

An investigation of fecal chymotrypsin activity on spot fecal specimens was carried out in three groups of subjects, divided as follows: 45 healthy controls (group C); 36 patients with gastroenterological diseases of extrapancreatic origin (group VP); and 42 patients with chronic pancreatitis (group CP). Nineteen patients of group CP underwent pancreozymin-secretin and NBT-PABA tests. The following results, expressed as mg of chymotrypsin/g of feces, were obtained: C = 0.610 +/- 0.203; CP = 0.291 +/- 0.154, p less than 0.001; VP = 0.560 +/- 0.234. FCT showed a sensitivity rate of 78.5% and a specificity rate of 71.6%. The fecal output of chymotrypsin correlated well with the pancreatic secretion of chymotrypsin (r = 0.59, p less than 0.01) and with the percentage of recovery of urinary PABA (r = 0.44, p less than 0.05). We conclude that chymotrypsin assay by the described method on spot stool specimens is a simple, reliable technique which may be considered a good screening test for pancreatic insufficiency. The test will not detect minimal pancreatic disease or minimal pancreatic dysfunction.