Which marker increases with biliary obstruction from tumors, cholelithiasis, biliary atresia, and hepatocellular disease (elevated)?

Which marker increases with biliary obstruction from tumors, cholelithiasis, biliary atresia, and hepatocellular disease (elevated)?

• A. ALP
• B. ALT
• C. AST
• D. GGTP

Answer: (A)

When bile flow is blocked, the cholestatic pattern shows up most clearly with enzymes produced by the bile ducts. Alkaline phosphatase is abundant in the bile duct epithelium, so obstruction from tumors, gallstones, or biliary atresia causes ALP to rise in the blood. This same pattern can appear in hepatocellular disease when cholestasis accompanies liver injury, though ALT and AST are more directly tied to hepatocyte damage. Gamma-glutamyl transferase can also increase with biliary obstruction, but alkaline phosphatase is the classic, most sensitive marker of cholestasis.

When bile flow is blocked, the cholestatic pattern shows up most clearly with enzymes produced by the bile ducts. Alkaline phosphatase is abundant in the bile duct epithelium, so obstruction from tumors, gallstones, or biliary atresia causes ALP to rise in the blood. This same pattern can appear in hepatocellular disease when cholestasis accompanies liver injury, though ALT and AST are more directly tied to hepatocyte damage. Gamma-glutamyl transferase can also increase with biliary obstruction, but alkaline phosphatase is the classic, most sensitive marker of cholestasis.