In obstructive jaundice, which of the following enzyme patterns is MOST characteristic?
- A Markedly raised alkaline phosphatase with disproportionately mild ALT elevation ✓
- B Markedly raised ALT with normal alkaline phosphatase
- C Raised GGT only with normal alkaline phosphatase
- D Raised LDH with normal transaminases
Correct answer: A. Markedly raised alkaline phosphatase with disproportionately mild ALT elevation
Explanation
In cholestatic/obstructive jaundice, bile back-pressure induces hepatic alkaline phosphatase (ALP) synthesis, causing a marked ALP rise (often >3× upper limit of normal) with only mild-to-moderate transaminase elevation. In contrast, hepatocellular disease shows predominantly elevated ALT/AST. GGT is also raised in obstruction but ALP elevation dominates the pattern.
Reference: Harper's Illustrated Biochemistry, 32nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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