Fecal elastase-1 is useful in the detection of steatorrhea in patients with pancreatic diseases but not after pancreatic resection

Abstract

Background: Fecal elastase-1(FE-1) has been suggested as an alternative to steatorrhea quantification to evaluate pancreatic insufficiency, but its diagnostic performance has not been compared with steatorrhea in chronic pancreatitis or after pancreatic resection.

Methods: The relationship between steatorrhea and FE-1 was studied in patients with chronic pancreatic disorders or pancreatic resection. Student's t test and ANOVA were used for statistical analysis, accepting 0.05 as limit for significance.

Results: Eighty-two patients were studied (42 non-operated; 40 previously submitted to pancreatic resection). Fat output was higher in operated than non-operated patients (29.2 ± 3.1 vs 9.9 ± 2.2 g/day, p < 0.001) FE-1 was more severely reduced in operated patients (202 ± 32.3 μg/g in non operated vs 68.6 ± 18.2 in operated patients; p < 0.001). Steatorrhea was significantly more severe in operated patients across different levels of FE-1. The relationship between FE-1 and steatorrhea was described by a power regression model, with a regression line significantly different in operated and non-operated patients (p < 0.001). A steatorrhea of 7 g (upper limit of normal range) was calculated by this regression line when FE-1 is 15 μg/g in non-operated, but as high as 225 μg/g in operated patients.

Conclusion: FE-1 is useful to identify pancreatic insufficiency. Steatorrhea is anticipated in non-operated patients only when FE-1 is below the limit for a confident measurement of our assay. In operated patients, steatorrhea may be present even if FE-1 is only slightly reduced, that suggests a role for non pancreatic factors. FE1 is not useful to identify operated patients at risk of malabsorption.