In biliary atresia, what is the consequence of reduced intraluminal bile acids?

• A. Increased fat absorption
• B. Fat and fat-soluble vitamin malabsorption
• C. No impact on digestion
• D. Increased micelle formation

Answer: (B)

When intraluminal bile acids are reduced, fat digestion and absorption suffer because bile acids emulsify fats and form micelles that solubilize lipids for uptake. In biliary atresia, bile flow into the intestine is blocked, so fewer bile acids reach the lumen. That leads to fat malabsorption and impaired absorption of fat-soluble vitamins (A, D, E, K). The other options don’t fit: fat absorption wouldn’t increase without bile acids, there is a digestion impact, and micelle formation decreases with fewer bile acids rather than increases.