Value of ethyl glucuronide in plasma as a biomarker for recent alcohol consumption in the emergency room

Aim: This emergency department (ED) study compared the value of plasma ethyl glucuronide (EtG) testing with the information about alcohol consumption obtained using the standard alcohol biomarkers gamma-glutamyltransferase (GGT) and carbohydrate-deficient transferring (CDT) and the AUDIT questionnaire. Methods: Minimally injured and clinically non-intoxicated male patients (n = 81) admitted to an ED were screened regarding their alcohol consumption, using the computerized AUDIT questionnaire and a paper-and-pencil assessment including the type, amount and time of alcohol intake. Blood samples were collected for determination of ethanol, EtG (LC-MS) and GGT in plasma and %CDT in serum (Axis-Shield %CDT immunoassay). Results: Out of the 81 patients, 23 (28%) were positive (>= 8 points) on the AUDIT questionnaire. Only 3 (4%) showed a detectable ethanol concentration (range 0.01-0.07 g/L) but 31 (38%) showed a detectable EtG (0.16-39.5 mg/L). In four patients, EtG was detectable in plasma for > 48 h after estimated completed elimination of ethanol. EtG was not correlated with the long-term biomarkers %CDT or GGT, or the AUDIT results, but with the time since estimated completed ethanol elimination. Conclusion: EtG testing in blood was found useful in the ED as a way to detect recent drinking, even in cases of a negative ethanol test, and to confirm abstinence from alcohol. This sensitive and specific short-term biomarker provides valuable additional information about individual drinking habits and might also be helpful to identify an alcohol hangover.