Detection of pancreatic steatorrhea by oral pancreatic function tests

Pancreolauryl and NBT-PABA tests were performed in urine of 54 patients with exocrine pancreatic insufficiency and, additionally, in serum of 29 of these patients. All patients underwent a secretin-pancreozymin test and a 72-hr fecal fat analysis. Pancreatic steatorrhea occurred (with only three exceptions) when the pancreolauryl test revealed a T/C ratio [recovery of the fluorescein of the test (T) and the control (C) day] of less than 10, or when serum fluorescein concentrations were below 0.5 microgram/ml. The NBT-PABA test also showed a negative correlation between urinary PABA excretion or serum PABA concentration and fecal fat excretion, but there was no diagnostically useful cutoff limit indicating decompensation of exocrine pancreatic insufficiency. These findings indicate that the pancreolauryl test may facilitate clinical evaluation of patients with chronic pancreatitis by simultaneously assessing exocrine pancreatic insufficiency as a cause and predicting pancreatic steatorrhea as a sequel of maldigestion. In clinical practice, the pancreolauryl test can be used as a parameter for deciding whether to initiate pancreatic enzyme substitution if direct pancreatic function tests and fecal fat analysis are not available.