In a patient with obstructive jaundice due to carcinoma head of pancreas, which enzyme pattern is MOST characteristic?

• A Disproportionate elevation of ALT over AST with normal gamma-GT
• B Marked elevation of alkaline phosphatase and gamma-GT with mild transaminase rise ✓
• C Isolated rise of AST with normal alkaline phosphatase
• D Elevated LDH-5 fraction with normal alkaline phosphatase

Explanation

Obstructive (cholestatic) jaundice produces marked induction and release of alkaline phosphatase (ALP, isoenzyme from bile canalicular membrane) and gamma-glutamyl transferase (GGT) due to biliary backpressure and enzyme synthesis induction; transaminases are only mildly elevated because hepatocyte necrosis is not the primary event. ALT > AST pattern with normal GGT is characteristic of viral hepatitis. LDH-5 elevation suggests hepatocellular necrosis.

Reference: Harper's Illustrated Biochemistry, 32nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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