Q1: Answer: B
Rationale: Bile acid diarrhea (BAD) is becoming more widely recognized as a cause of chronic diarrhea. There are four associated types of BAD: Type 1 BAD is associated with ileal dysfunction with impaired reabsorption; type 2 BAD is considered primary or idiopathic BAD and occurs in the absence of ileal or obvious gastrointestinal disease; type 3 BAD is associated with gastrointestinal disorders, such as small intestinal bacterial overgrowth, celiac disease, or chronic pancreatitis; a fourth category of BAD may result from excessive hepatic bile acid synthesis caused by medications. This patient appears to have type 2 BAD; therefore, Answer B is correct. BAD has been shown to account for about one-third of patients with chronic diarrhea or irritable bowel syndrome with diarrhea.
References
1. Camilleri M. Bile acid diarrhea: prevalence, pathogenesis, and therapy. Gut Liver. 2015 May 23;9[3]:332-9.
2. Wedlake L., et al. Systematic review: The prevalence of idiopathic bile acid malabsorption as diagnosed by SeHCAT scanning in patients with diarrhoea-predominant irritable bowel syndrome. Aliment Pharmacol Ther. 2009;30:707-17.
