Evaluating the potential role of phosphatidylethanol as sensitive and specific biomarker for monitoring sobriety in liver transplant candidates
08 August 2017 (online)
Alcohol cirrhosis is a common diagnosis in liver transplant (LTx) candidates. Monitoring sobriety therefore is part of transplantation guidelines., Using biomarkers including ethyl-glucuronide (EtG) in urine (uEtG) or hair (hEtG) is mandatory in Germany. However, a number of influencing factors including renal impairment limit its use. Therefore, we aimed at evaluating the usefulness of phosphatidylethanol (PEth) pre liver transplantation by comparing the results with routine parameters including uEtG and additionally hEtG and self-reports.
The study design was open, monocentric and prospective. In total, 66 patients of our transplant out-patient clinic (31 female, 35 male; mean age 53.29 ± 12.0 years) were enrolled for the study. 53 were already listed for LTx and 13 were potential candidates. 25 patients had the diagnosis of an alcohol use disorder. Each patient received the Alcohol Use Disorders Identification Test (AUDIT) and timeline follow-back questionnaire (TLFB). Blood, urine and hair samples were drawn for monitoring the alcohol intake employing routinely used biomarker tests including uEtG and additionally hEtG and PEth dry-blood spot as experimental parameter.
Twenty-five patients reported any alcohol consumption in the TLFB and 33 patients had > 1 point in the AUDIT. Positive biomarker results were detected in 5/65 patients for uEtG, 9/65 for hEtG and 34/66 for PEth. Among the 25 patients with an alcoholic cirrhosis, 21 (84.0%) and 13 among the 41 patients with other liver diseases (31.7%) were PEth positive. In comparison, patients with alcoholic cirrhosis had a positive uEtG and hEtG value in 16% and patients with other liver diseases in 12.2 and 22.0%, respectively. Positive uEtG and hEtG tests correlated significantly with higher PEth values. Alcohol consumption over the last week, last two weeks, last month and last six months correlated with higher PEth values, especially if alcohol consumption was admitted within the last two weeks (p < 0.001) and the last months (p = 0.001).
In conclusion, our data suggest advantages of PEth as compared to uEtG in monitoring sobriety of patients on the liver transplant waiting list. Its higher sensitivity and independency from renal function as well as its good practicability in the clinical setting favour the use of PEth.