[Serum paraaminobenzoic acid following the use of N-benzoyl-L-tyrosyl-paraaminobenzoic acid in the diagnosis of pancreatic insufficiency].

In 25 patients with chronic exocrine pancreatic insufficiency and 37 controls, the PABA test was compared with the concentration of chymotrypsin in stool. In additional 16 patients the test could not be evaluated (rate 21%). By determination of the PABA levels in serum before and one hour after ingestion of N-benzoyl-L-tyrosyl-PABA the test can be shortened and simplified: 1 hour serum levels in 9 patients with exocrine pancreatic insufficiency were 0.5 +/- 0.5 nMol/ml compared with 8 controls with 6.4 +/- 2.0 nMol/ml. PABA serum levels correlated significantly with chymotrypsin in stool. Compared with the conventional PABA test, since it is easily applicable in outpatients and the results are not influenced by medication or food.