Managing bile acid diarrhea: aspects of contention

IntroductionBile acid diarrhea is a common cause of bowel symptoms and often goes unrecognized or misdiagnosed. Many aspects of management remain contentious.Areas CoveredThe primary, idiopathic condition should be suspected in people with functional diarrhea or diarrhea-predominant irritable bowel syndrome. Secondary causes include ileal resection, inflammation, and post-cholecystectomy. Diagnostic tests vary globally, being unavailable in many countries, and further refinement of testing strategy is needed. Management is usually long-term symptom control, rather than reversal of the causative factors, which are still being defined. Bile acid sequestrants remain the main drugs used. They are relatively inexpensive, and better-quality data is now available for colesevelam. However, optimal use, including timing and formulation, needs clarification. The GLP-1 receptor agonist, liraglutide, is also effective, although mechanisms of action and whether this effect is common to other class members is unclear. They are more expensive, and availability varies. FXR agonists can also be effective but require further validation. The role of dietary factors in symptom development is a major patient concern, needing more formal studies.Expert opinionTo build on recent findings, bile acid diarrhea needs further investment into causes, diagnosis and therapy to guide present and future patient care. The condition known as bile acid diarrhea (BAD) causes frequent loose stools, which need to be passed urgently, sometimes causing incontinence. It can be a complication of surgery or other intestinal disorders, and gives similar symptoms to IBS. It is not widely known and clinicians often fail to diagnose it. In this article, we review recent publications about how to make the diagnosis of BAD. Some of these are contentious and there may be limited availability of the tests or poor accuracy. We then review current treatments and how to best manage BAD. There are some new treatments, which are not yet fully proven or accepted for general use. We review these and express opinions regarding the current best practices in diagnosis and treatment, and how these may change in the next 5 years.