Systematic review: the management of chronic diarrhoea due to bile acid malabsorption.

Background: Bile acid malabsorption (BAM) is a common, yet under-recognised, cause of chronic diarrhoea, with limited guidance available on the appropriate management of patients with BAM.

Aim: To summarise the evidence supporting different treatments available for patients with bile acid malabsorption, noting their impact on clinical outcomes, tolerability and associated side effects.

Methods: A literature search was conducted through PubMed, the Cochrane Database of Systematic Reviews and Scopus. Relevant articles studied patients who had been diagnosed with BAM and were clinically assessed before and after therapy.

Results: A total of 30 relevant publications (1241 adult patients) were identified, which investigated the clinical response to drugs, including colestyramine, colestipol, colesevelam, aluminium hydroxide and obeticholic acid. The most commonly used diagnostic test of bile acid malabsorption was the SeHCAT test (24 studies). Colestyramine treatment was by far the most studied of these agents, and was successful in 70% of 801 patients (range: 63-100%).

Conclusions: Colestyramine and colestipol are generally effective treatments of gastrointestinal symptoms from BAM, but may be poorly tolerated and reduce the bioavailability of co-administered agents. Alternative therapies (including colesevelam and aluminium hydroxide) as well as dietary intervention may also have a role, and the promising results of the first proof-of-concept study of obeticholic acid suggest that its novel approach may have an exciting future in the treatment of this condition. Future trials should employ accurate diagnostic testing and be conducted over longer periods so that the long-term benefits and tolerability of these different approaches can be evaluated.