In a patient with suspected early liver disease whose standard liver function tests are all normal, which single test is the most sensitive indicator of hepatic dysfunction, including portosystemic shunting?

• A Serum albumin concentration
• B Serum alkaline phosphatase
• C Fasting serum bile acid concentration ✓
• D Blood ammonia level

Explanation

Serum bile acids are extracted almost completely by a healthy liver on first pass. Any reduction in hepatocellular uptake or any portosystemic shunt allows bile acids to spill into systemic blood, so fasting serum bile acid levels rise earlier and more consistently than bilirubin, transaminases or albumin in early liver disease. Albumin has a long half-life and falls late, alkaline phosphatase reflects cholestasis rather than overall function, and ammonia is insensitive and variable.

Reference: Harper's Illustrated Biochemistry, 31st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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