ASGE Annual GI Advanced Practice Provider Course (On-demand) (Day Two) | March 2026-Decoding Abnormal LFTs: Interpretation and Action

Video Transcription

Video Summary

The speaker explains how to interpret “abnormal liver tests” by clarifying confusing terminology and grouping tests by what they actually measure. AST and ALT are <strong>liver injury tests</strong> (enzymes that leak from damaged hepatocytes), not true “liver function tests.” True liver <strong>synthetic function</strong> is assessed mainly by <strong>albumin</strong> and <strong>PT/INR</strong>, while <strong>bilirubin</strong> reflects hepatic transport/excretory function (and cholestasis) but is not an enzyme. <strong>Cholestatic enzymes</strong> include <strong>alkaline phosphatase (ALP)</strong>, <strong>GGT</strong>, and <strong>5’-nucleotidase</strong>; GGT/5’NT help confirm whether an elevated ALP is from liver rather than bone. Patterns matter: hepatocellular injury shows AST/ALT disproportionately high; cholestasis shows ALP (± bilirubin) disproportionately high. Timing differs: AST/ALT often rise first, then ALP, then bilirubin. Case examples highlight ischemic “shock liver” with AST/ALT in the thousands, cholangitis from bile duct obstruction needing antibiotics and imaging/surgery consult, and acetaminophen toxicity causing acute liver failure requiring NAC and possible transplant evaluation.

Asset Subtitle

John A. Martin, MD, FASGE

Keywords

abnormal liver tests interpretation

AST ALT hepatocellular injury pattern

albumin PT INR synthetic liver function

alkaline phosphatase GGT 5-nucleotidase cholestasis

bilirubin transport excretory function

acute liver failure shock liver acetaminophen toxicity