Bile Acid-induced Diarrhea

 

Bile-acid induced diarrhea (BAD) is a prevalent condition in people. It is estimated that 40% of patients with Crohn’s disease and 32 % of patients with diarrhea-predominant irritable bowel syndrome are suffering from BAD. Affected patients typically respond to bile acid sequestrants such as cholestyramine. However, mainly due to lack of diagnostic tools, gastroenterologists often fail to recognize BAD. Thus, it is considered an underdiagnosed and undertreated condition in human medicine.
According to several recent studies, bile acid dysmetabolism also occurs in dogs with chronic enteropathies. It has further been shown that dogs with chronic enteropathies have significantly decreased expression of a bile acid transport protein in the ileum compared to healthy dogs, which correlates with fecal bile acid dysmetabolism. Recently, the first case report on successful cholestyramine treatment in two dogs with chronic refractory diarrhea was published. Since then, the author has found several other dogs responding to cholestyramine. The focus of this lecture will be the pathogenesis, diagnosis and treatment of BAD in dogs. Furthermore, the clinical picture and results from analysis of fecal markers, such as dysbiosis index, primary bile acids, and others, in dogs with chronic diarrhea responding to versus not responding to cholestyramine will be discussed.
Bile acid-induced diarrhea is a very novel clinical concept in dogs, and there is still a lot to learn. However, awareness and treatment of this condition may improve the quality of life in affected dogs with chronic non-responsive or poorly responsive diarrhea.