Urinary ethyl glucuronide as a novel screening tool in patients pre- and post-liver transplantation improves detection of alcohol consumption.

UNLABELLED: Optimal selection of liver transplant candidates and early detection of alcohol relapse after orthotopic liver transplantation (OLT) is necessary to improve long-term outcomes. In this study, urinary ethyl glucuronide (uEtG) was prospectively evaluated as a novel screening tool for alcohol detection in the transplant setting. Overall, 141 liver transplant candidates and recipients, visiting the outpatient clinic for a total of 308 times, were included. At each visit, the alcohol markers, uEtG, ethanol, methanol, and carbohydrate-deficient transferrin (CDT), as well as the state markers, alanine transaminase, aspartate transaminase, gamma glutamyl transpeptidase (GGT), and mean corpuscular volume (MCV), were determined, then compared to patients' self-reports on alcohol intake. Urinary EtG significantly increased the detection rate of alcohol consumption, compared to the other alcohol markers (P < 0.001). In 93% of patients and at 92.5% of visits with positive alcohol markers, alcohol intake was detected by uEtG and/or CDT. Sensitivity and specificity of uEtG were 89.3% and 98.9% and of CDT were 25% and 98.6%, respectively. Urinary EtG was the best independent predictor of alcohol consumption in univariate and multivariate analysis (positive predictive value: 89.3%; negative predictive value: 98.9%; odds ratio: 761.1; P < 0.001). It showed a superior prediction rate, when compared to established alcohol and state markers, as well as to the combination of CDT with MCV and GGT, assessed by net reclassification improvement (NRI) (NRI: 1.01, P < 0.001; NRI: 1.755, P < 0.001).
CONCLUSION: uEtG is a sensitive, specific, and reliable marker for the detection of recent alcohol intake pre- and post-OLT. In combination with CDT, uEtG should be considered as a tool for routine alcohol screening within the transplant setting.