Direct ethanol metabolite ethyl glucuronide. Its value as alcohol intake and recurrence marker, methods of detection and prospects

In clinical as well as in forensic practice biological state markers of high sensitivity and specificity capable of monitoring alcohol consumption of those in treatment for alcohol dependence or poly-drug abusers are required. The known markers cannot be considered satisfactory in respect of these parameters. Furthermore, they do not cover the entire time axis for alcohol consumption. These traditional markers are often influenced besides by alcohol, by age, gender and various of substances and non-alcohol-associated diseases. Ethyl glucuronide (EtG) is a non volatile, water soluble, stable upon storage, direct metabolite of ethanol with a molecular weight of 222 g/mol that was determined by our group in more than 1200 samples of body fluids, tissues and hair from over 200 patients, almost 200 drivers and postmortem with different GC/MS and ESI-LC/MS-MS methods using deuterium-labelled EtG as internal standard. With its specific time frame of detection intermediate between short-term and long-term markers and a particularly high sensitivity and specificity, ethyl glucuronide is a promising marker of alcohol consumption in general that can be detected for an extended time period after the complete elimination of alcohol from the body (up tp 80 h) and a marker for relapse control enabling the therapist to intervene at an early stage of relapsing behaviour. The complementary use of EtG together with other upcoming markers of alcohol consumption like phosphatidyl ethanol should lead to an improvement in treatment outcome, quality of life and cost reduction.