Gamma-Glutamyl Transferase (GGT)

Hepatic Panel

Normal Reference Ranges

Adult

Male: 15-73 | Female: 12-43 U/L

Pediatric

10-50 U/L

Clinical Significance

Highly sensitive indicator of biliary tract disease. Often used to differentiate the source of an elevated Alkaline Phosphatase (ALP); if GGT is also high, the ALP is likely of hepatic (not bone) origin.

Causes of High

  • Biliary obstruction (Cholestasis)
  • Chronic alcohol abuse
  • Drug-induced liver injury (Phenytoin, Phenobarbital)
  • Fatty liver disease

Causes of Low

  • Normal finding