Background
- Liver enzyme in microsomes that catalyzes transfer of γ-glutamyl group from peptides to other amino acids
Interpretation
- About 90% sensitive for cholestasis (with ALP)
- Often only rise after several days
- Isolated elevation of GGT may be caused by enzyme induction from alcohol or aromatic medications, without liver disease1
- Aromatic medications include, commonly, phenobarbital, phenytoin, and others
- Elevation is usually about twice the upper limit of normal
- Can also see isolated elevations in COPD, AKI or CKD, and acute myocardial infarction2
- May be elevated in NAFLD and hepatitis C and other liver or biliary diseases
