CLINICAL STUDIES ON THE EXOCRINE PANCREATIC FUNCTION TEST BY ORAL ADMINISTRATION OF N-BENZOYL-L-TYROSYL-PABA COMBINED WITH THE PABA ABSORPTION TEST

Abstract

An oral exocrine pancreatic function test (PFD test) using N-benzoyl-L-tyrosyl-P-aminobenzoic acid (BT-PABA) is influenced by the intestinal absorption of the P-aminobenzoic (PABA) and the renal function.
In this study, the urinary excretion rate of PABA was examined by the administration of 170 mg PABA (PABA test) and then a diagnostic evaluation index was created by subtracting the PFD value from the PABA value. The PABA minus the PFD value was used to determine the percentage of PABA not hydrolized by pancreatic chymotrypsin in the small intestine. This index was used in studying patients with pancreatic diseases by comparing the results of the PS test with thsoe of the PFD test.
A significant correlation was obtained between the PABA minus the PFD value and maximum bicarbonate concentration (P<0.001) and also amylase output (P<0.05) in the PS test. These correlation were improved comparing with those of PFD values.
The PABA minus the PFD value was significantly increased in chronic pancreatitis with calcification (P<0.001) and without calcification (P<0.05), while the PFD value did not show significnat decrease in chronic pancreatitis without calcification. Futhermore, the PABA minus the PFD value revealed normal in patients with false positive PFD test.
These results indicate that this modified method can present a more accurate exocrine pancreatic function than the PFD test.