Biomarkers for detection of alcohol consumption in liver transplantation

Table 1 Biomarkers for alcohol consumption used in the liver transplant setting

Biomarker	Biological compartment	Window of detection	Confounding factors	Cut off	Sensitivity	Specificity	Number of patients	Ref.
Indirect markers
GGT	Serum	-	Liver disease	-	49.6	83.9	558	[33]
				< 55 U/l	85.7	39.7	141	[17]
MCV	Serum	-	Hematological diseases, vitamin deficiencies	< 94 fL	75.0	55.7	141	[17]
AST	Serum	-	Liver disease, muscle alterations	< 35 U/L	67.9	56.3	141	[17]
ALT	Serum	-	Liver disease	< 50 U/L	29.6	76.2	141	[17]
%CDT	Serum	1-2 wk	Hyperbilirubinemia, liver cirrhosis/disease, smoking, sepsis, anorexia nervosa, airway diseases, rare genetic variants, transferrin levels	≥ 2.5%	52.7	87.8	558	[33]
				> 2.6%	25.0	98.6	141	[17]
				> 2.6%	-	-	88	[18]
Direct markers
Breath alcohol	Exhalation air	10-12 h	Alcohol containing mouth wash	≥ 0.01 g/L	-	-	18	[6]
EtOH	Serum	10-12 h	Unknown	≥ 0.1 g/kg	-1	-1	141	[17]
				-	-	-	41	[55]
MeOH	Serum	up to 48 h	Unknown	≥ 5 mg/L	22.2	99.3	141	[17]
				≥ 1.5 mg/L	-	-	41	[55]
EtG	Urine	up to 80 h	Heavily impaired kidney function, high amounts of baker's yeast/sauerkraut, alcohol containing mouthwash, storage above 4 °C before measurement	≥ 0.5 mg/L	-	-	18	[6]
					89.3	98.9	141	[17]
EtG	Hair	up to 6 mo	EtG containing hair treatment, heavily impaired kidney function	≥ 7 pg/mg	76.0	91.0	88	[18]

¹No sensitivity/specificity calculated, since only 1 of 141 patients had elevated EtOH. In the case of CDT, only studies using the HPLC method for determination of %CDT are reported. - not reported in the cited manuscript. GGT: Gamma-glutamyl transferase; MCV: Mean corpuscular volume; AST: Aspartate amino transferase; ALT: Alanine amino transferase; CDT: Carbohydrate deficient transferrin; EtOH: Ethanol; HPLC: High-performance liquid chromatography; MeOH: Methanol; EtG: Ethyl glucuronide.