In laboratory liver function tests, which pattern best distinguishes cholestasis from hepatocellular injury?

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Multiple Choice

In laboratory liver function tests, which pattern best distinguishes cholestasis from hepatocellular injury?

When liver injury is due to bile flow obstruction (cholestasis), the pattern from the enzymes reflects the bile ducts being affected. Alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) rise because these enzymes are produced by the bile duct epithelium and traffic in with biliary obstruction. The transaminases (ALT and AST) are only modestly elevated in pure cholestasis, since the main injury isn’t hepatocyte death. In hepatocellular injury, the problem is damage to liver cells themselves, so ALT and AST rise markedly as those cells leak their enzymes. ALP tends to be less elevated unless there is some cholestasis or biliary involvement. So the pattern that best distinguishes them is that cholestasis shows high ALP and GGT with only modest transaminase elevation, while hepatocellular injury shows a marked rise in ALT/AST with relatively milder ALP.

When liver injury is due to bile flow obstruction (cholestasis), the pattern from the enzymes reflects the bile ducts being affected. Alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) rise because these enzymes are produced by the bile duct epithelium and traffic in with biliary obstruction. The transaminases (ALT and AST) are only modestly elevated in pure cholestasis, since the main injury isn’t hepatocyte death.

In hepatocellular injury, the problem is damage to liver cells themselves, so ALT and AST rise markedly as those cells leak their enzymes. ALP tends to be less elevated unless there is some cholestasis or biliary involvement.

So the pattern that best distinguishes them is that cholestasis shows high ALP and GGT with only modest transaminase elevation, while hepatocellular injury shows a marked rise in ALT/AST with relatively milder ALP.

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