Background: Quantitative determination of pancreatic elastase-1 (E1) in stools has been proposed as a novel, noninvasive test of pancreatic function. The aim of the study was to verify its role in the differential diagnosis of chronic diarrhea.
Methods: E1 was measured in spot stool samples of 50 patients with pancreatic disease (PD), 62 with inflammatory bowel disease (IBD), 45 with chronic diarrhea (CD), 34 with other gastroduodenal and liver disease (gastrointestinal; GI), and in 18 normal controls, by a commercial kit (Schebo-Tech., Wettemburg, Germany).
Results: In PD, patients with severe damage and diarrhea displayed E1 levels below 100 microg/g; normal values were found in mild-moderate disease. Abnormal values were detected in 4 CD and in 14 IBD patients, either in the presence of severe protein malnutrition or in patients with previous ileo-anal pouch anastomosis and pouchitis. In nine cases, values reverted to normal after adequate treatment. Diagnostic accuracy of E1 in discriminating diarrhea of pancreatic and nonpancreatic origin was: SS, 97%; SP, 84%; VP+, 66%; VP-, 100%.
Conclusion: 1) The finding of a normal E1 value rules out a malabsorption of pancreatic origin. 2) in CD and IBD, decreased E1 might be owing to bacterial elastase degradation (pouchitis) or transient defective pancreatic enzyme secretion.