The diagnostic value of the oral pancreatic function test.

An oral pancreatic function test (PFT) using the synthetic peptide N-benzoyl-L-tyrosyl-p-aminobenzoic acid can assess pancreatic exocrine function, since urinary recovery of the ingested dose is an indirect index of chymotryptic activity. We have studied 34 subjects using this oral PFT, which correctly distinguished the control group (8 subjects) from the pancreatitis group (10 patients), results correlating well with Lundh test findings. However, the test was falsely abnormal on 9 out of 16 occasions in patients with bowel or liver disease. We therefore conclude that the present test cannot distinguish small-bowel disease from pancreatic disease, which is often the diagnostic problem, and is also frequently falsely abnormal in the presence of chronic liver disease.