Diagnostic and therapeutic yield of 72h stool collection combined with bile acid quantification: a retrospective analysis

Background and study aims: Chronic idiopathic diarrhea represents a diagnostic and therapeutic challenge to gastroenterologists. We aimed to explore the diagnostic and therapeutic yield of 72h stool collection combined with bile acid quantification, in chronic diarrhea patients, to differentiate bile acid malabsorption from other causes of diarrhea and thus enabling tailored treatment.

Patients and methods: We performed a retrospective study on 252 stool collections combined with bile acid quantification. Descriptive statistics, Pearson correlation analysis and ANOVA with post hoc between-group t-tests were used.

Results: Idiopathic bile acid diarrhea was present in up to one third of patients with diarrhea-predominant IBS and functional diarrhea. Steatorrhea was highly prevalent both in patients with a clinical suspicion of fat malabsorption (57%) as well as patients with non-specific diarrhea (23%). We show a significant difference in fecal bile acid and fat content in patients with vs. without predisposing risk factors for bile acid or fat malabsorption (e.g. cholecystectomy). The prevalence of steatorrhea was also significantly higher in patients with previous enteric resection or bariatric surgery. Bile acid diarrhea was significantly more frequent in patients with previous colonic resection, probably due to combined resection of a distal ileal segment during right hemicolectomy. We could not show higher rates of bile acid diarrhea post-cholecystectomy compared to the other groups.

Conclusion: Bile acid diarrhea and steatorrhea are prevalent findings in patients with chronic diarrhea. Using this 72h stool analysis with bile acid quantification can help clinicians in the complex management of chronic diarrhea.

Keywords: Chronic diarrhea, fecal bile acids, 72h stool collection, bile acid malabsorption.