Which is a potential cause of diarrhea in Crohn's disease?

In Crohn's disease, particularly when the ileum is affected or surgically resected, one of the potential causes of diarrhea is excess bile salts. The ileum is responsible for the reabsorption of bile salts, which are critical for the digestion and absorption of fats. When a section of the ileum is removed or severely damaged, the body may not be able to reabsorb these bile salts effectively.

As a result, the unabsorbed bile salts can enter the colon. In the colon, they can attract water and lead to increased osmotic diarrhea. This condition, known as bile acid malabsorption, is a common consequence after ileal resection and contributes significantly to diarrhea in patients with Crohn’s disease. The presence of bile salts in the colon can also stimulate increased intestinal secretion and motility, which compounds the problem.

While intestinal hypermotility can also be a factor in diarrhea, it is more commonly a symptom resulting from various pathological processes rather than a direct cause. Other options, such as allergies to gluten and viral infections, are less relevant to Crohn's disease specifically and are not typically considered primary causes of diarrhea in this context.