Understanding Liver Function Test Results: What Does an ALT of 46 Mean?

ALT (alanine aminotransferase) is a hepatocellular enzyme; serum elevation indicates hepatocyte injury.

Reference Range

Typical adult male: 7–55 U/L (lab-dependent). ALT 46 U/L is within normal limits.

Contextual Interpretation

• Isolated mild elevation (<2× ULN): common; consider NAFLD, alcohol, medications (statins, NSAIDs), metabolic syndrome, viral hepatitis.
• Trend matters: rising trend > single value.
• AST/ALT ratio: >2 suggests alcoholic liver disease; <1 suggests viral/NAFLD.
• Associated labs: AST, ALP, GGT, bilirubin, INR, albumin, platelets, viral serologies, Ferritin, A1c, lipids.

When to Act

• ALT >2× ULN persistent >3 months.
• Symptoms (RUQ pain, jaundice, fatigue).
• Risk factors (heavy alcohol, obesity, diabetes, family history).

Single normal ALT does not exclude liver disease (cirrhosis can have normal ALT). Clinical correlation essential.