Table 1.

Biomarkers in diagnosis and prognosis of patients with of AUD [14,37]

Biomarker	Biology	Significance	Cut-off value
GGT	Marker of alcohol liver injury	Unspecific. Liver dysfunction and oxidative stress.
Transaminase enzymes (ALT, AST)	Marker of alcohol liver injury	Screening for liver dysfunction in alcohol users.	High specificity if AST/ALT ratio >2
Blood cell counts (macrocytic anemia, thrombocytosis)	Marker of alcohol liver injury	Unspecific. Normalization in 2–4 months.
Urine/blood ethanol (EtOH)	Direct alcohol metabolite	Specific. Recent alcohol intake or alcohol intoxication. Short half-life.	Positive urine EtOH ≥20 mg/dL
			Positive blood EtOH >30 mg/dL
Carbohydrate-deficient transferrin (CDT)	Alcohol-derive metabolites	High specificity, low sensitivity for alcohol recent use (2–3 weeks)	CDT <60 mg/L (normal value); 60–100 mg/L (probable alcoholism) and >100 mg/L (very high probability of alcoholism)
Ethyl-glucuronide (EtG), ethyl sulfate (EtS)	Alcohol-derive metabolites	Recent alcohol intake (3–4 days)High inter-individual variations	Positive EtG >100 ng/mL
			Positive EtS >25 ng/mL
Phosphatidylethanol (PEth)	Alcohol-derive metabolites	Recent alcohol intake (2–4 weeks). Differentiates alcohol- from non- alcohol induced liver disease.	PEth <20 ng/mL (light or no), 20–199 ng/mL (significant) and >200 ng/mL (heavy)
GGT-CDT combination	Marker of alcohol liver injury + alcohol-derive metabolite	Improves sensitivity and specificity of detecting AUD

AUD, alcoholic use disorder; GGT, gamma-glutamyl transferase; ALT, alanine transaminase; AST, aspartate transaminase.