Gastroenterology MCQ Answer 29

Answer: a, c

Some 80% to 90% of bile salts secreted into the small intestine as micelles are reabsorbed and returned to the liver through the portal circulation. This circular flow of bile is termed the enterohepatic circulation. In the liver, bile salts are resecreted and stored in the gallbladder in preparation for the next meal. The reabsorption process of bile is both passive and active. Passive absorption occurs along the entire length of the small bowel and depends on the lipid solubility of the bile salt. Glycine bile conjugates are more soluble than taurine conjugates. As much as 50% of bile is passively reabsorbed. Active absorption of bile occurs only in the terminal ileum. A small amount of bile escapes into the colon, where it is deconjugated by bacteria, promoting lipid solubility and further passive absorption. High colonic concentration of bile salts promote diarrhea by inhibiting sodium and water absorption. This commonly occurs in patients with ileal resection and can be treated with the bile-binding resin, cholestyramine.

Category: Gastroenterology MCQs