A pattern of liver enzymes most consistent with obstructive biliary disease would show which of the following?

• A. Marked elevation of alkaline phosphatase with mild AST/ALT
• B. Marked elevation of transaminases with normal alkaline phosphatase
• C. Normal enzyme levels
• D. Decreased alkaline phosphatase

Answer: (A)

When bile flow is obstructed, the biliary ducts become a source of increased enzyme release, especially alkaline phosphatase. Alkaline phosphatase is abundant in the cells lining the bile ducts, so blockage causes a marked rise in its level. At the same time, hepatocyte injury tends to be limited in obstruction, so the transaminases (AST and ALT) rise only modestly. This combination—much higher alkaline phosphatase with only mild transaminase elevation—best fits obstructive biliary disease.

If the pattern showed marked transaminase elevation with normal alkaline phosphatase, that would point more toward primary hepatocellular injury rather than obstruction. Normal enzyme levels or a decrease in alkaline phosphatase would not reflect obstructive cholestasis.