The ethanol conjugate ethyl glucuronide is a useful marker of recent alcohol consumption

ACG Clinical Guideline: Alcohol-Associated Liver Disease

ABSTRACT

Alcohol-associated liver disease (ALD) is the most common cause of advanced hepatic disease and frequent indication for liver transplantation worldwide. With harmful alcohol use as the primary risk factor, increasing alcohol use over the past decade has resulted in rapid growth of the ALD-related healthcare burden. The spectrum of ALD ranges from early asymptomatic liver injury to advanced disease with decompensation and portal hypertension. Compared with those with other etiologies of liver disease, patients with ALD progress faster and more often present at an advanced stage. A unique phenotype of advanced disease is alcohol-associated hepatitis (AH) presenting with rapid onset or worsening of jaundice, and acute on chronic liver failure in severe forms conveying a 1-month mortality risk of 20%-50%. The model for end stage disease score is the most accurate score to stratify AH severity (>20 defined as severe disease). Corticosteroids are currently the only available therapeutic with proven efficacy for patients with severe AH, providing survival benefit at 1 month in 50%-60% of patients. Abstinence of alcohol use, a crucial determinant of long-term outcomes, is challenging to achieve in ALD patients with concurrent alcohol use disorder (AUD). As patients with ALD are rarely treated for AUD, strategies are needed to overcome barriers to AUD treatment in patients with ALD and to promote a multidisciplinary integrated care model with hepatology, addiction medicine providers, and social workers to comprehensively manage the dual pathologies of liver disease and of AUD. Liver transplantation, a definitive treatment option in patients with advanced cirrhosis, should be considered in selected patients with AH, who are unresponsive to medical therapy and have a low risk of relapse to posttransplant alcohol use. Level of evidence and strength of recommendations were evaluated using the Grading of Recommendations, Assessment, Development, and Evaluations system. This guideline was developed under the American College of Gastroenterology Practice Parameters Committee.

Ethyl glucuronide, a marker of alcohol consumption, correlates with metabolic markers of oxidant stress but not with hemolysis in stored red blood cells from healthy blood donors

BACKGROUND

Red blood cell (RBC) storage in the blood bank is associated with the progressive accumulation of oxidant stress. While the mature erythrocyte is well equipped to cope with such stress, recreative habits like alcohol consumption may further exacerbate the basal level of oxidant stress and contribute to the progress of the storage lesion.

STUDY DESIGN AND METHODS

RBC levels of ethyl glucuronide, a marker of alcohol consumption, were measured via ultra-high-pressure liquid chromatography coupled with high-resolution mass spectrometry. Analyses were performed on 599 samples from the recalled donor population at Storage Days 10, 23, and 42 (n = 250), as part of the REDS-III RBC-Omics (Recipient Epidemiology Donor Evaluation Study III Red Blood Cell-Omics) study. This cohort consisted of the 5th and 95th percentile of donors with extreme hemolytic propensity out of the original cohort of 13,403 subjects enrolled in the REDS-III RBC Omics study. Ehtyl glucuronide levels were thus correlated to global metabolomics and lipidomics analyses and RBC hemolytic propensity.

RESULTS

Ethyl glucuronide levels were positively associated with oxidant stress markers, including glutathione consumption and turnover, methionine oxidation, S-adenosylhomocysteine accumulation, purine oxidation, and transamination markers. Decreases in glycolysis and energy metabolism, the pentose phosphate pathway and ascorbate system were observed in those subjects with the highest levels of ethyl glucuronide, though hemolysis values were comparable between groups.

CONCLUSION

Though preliminary, this study is suggestive that markers of alcohol consumption are associated with increases in oxidant stress and decreases in energy metabolism with no significant impact on hemolytic parameters in stored RBCs from healthy donor volunteers.

Urinary Ethyl Glucuronide Can Be Used as a Biomarker of Habitual Alcohol Consumption in the General Population

BACKGROUND

Alcohol consumption is a frequently studied risk factor for chronic diseases, but many studies are hampered by self-report of alcohol consumption. The urinary metabolite ethyl glucuronide (EtG), reflecting alcohol consumption during the past 72 h, is a promising objective marker, but population data are lacking.

OBJECTIVE

The objective of this study was to assess the reliability of EtG as a marker for habitual alcohol consumption compared with self-report and other biomarkers in the general population.

METHODS

Among 6211 participants in the Prevention of Renal and Vascular End-Stage Disease (PREVEND) cohort, EtG concentrations were measured in 24-h urine samples. EtG was considered positive when concentrations were ≥100 ng/mL. Habitual alcohol consumption was self-reported by questionnaire (categories: no/almost never, 1-4 units per month, 2-7 units per week, 1-3 units per day or ≥4 units per day). Plasma HDL cholesterol concentration, erythrocyte mean corpuscular volume (MCV), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyltransferase (GGT) were determined as indirect biomarkers of alcohol consumption. Sensitivity, specificity, positive and negative predictive value, and proportions of agreement between reported consumption and EtG were calculated. To test the agreement of EtG concentration and alcohol consumption in categories, linear regression analysis was performed. In addition, the association between EtG concentrations and indirect biomarkers was analyzed.

RESULTS

Mean age was 53.7 y, and 52.9% of participants men. Of the self-reported abstainers, 92.3% had an EtG concentration <100 ng/mL. Sensitivity was 66.3%, positive predictive value was 96.3%, and negative predictive value was 47.4%. The proportion of positive agreement was 78.5%, and the proportion of negative agreement was 62.7%. EtG concentrations were linearly associated with higher categories of alcohol consumption (P-trend < 0.001), adjusted for age, sex, and renal function. EtG was positively related to MCV, HDL cholesterol, and GGT but not to AST and ALT concentrations.

CONCLUSIONS

This study shows that urinary EtG is in reasonable agreement with self-reported alcohol consumption and therefore can be used as an objective marker of habitual alcohol consumption in the general population.

Contingency management intervention targeting co-addiction of alcohol and drugs among American Indian adults: Design, methodology, and baseline data

BACKGROUND/AIMS

American Indian adults have some of the highest alcohol abstinence rates compared to the overall US population. Despite this, many American Indian people are more likely to concurrently use alcohol and illicit drugs and are less likely to participate and remain in outpatient treatment for alcohol and other drug use compared to the general US population. There is limited knowledge about effective interventions targeting alcohol and drug co-addiction among American Indian adults. Contingency management is a behavioral intervention designed to increase drug abstinence by offering monetary incentives in exchange for drug and alcohol negative urine samples. We aim to evaluate and describe a culturally tailored contingency management intervention to increase alcohol and other drug abstinence among American Indian adults residing in a Northern Plains reservation.

METHODS

This 2 × 2 factorial, randomized controlled trial currently includes 114 American Indian adults with alcohol and/or drug dependence who are seeking treatment. Participants were randomized into one of four groups that received (1) contingency management for alcohol, (2) contingency management for other drug, (3) contingency management for both substances, or (4) no contingency management for either substance. We present descriptive, baseline data to characterize the sample and describe the modified contingency management approach that is specific to the community wherein this trial was being conducted.

RESULTS

The sample is 49.1% male, with an average age of 35.8 years (standard deviation = 10.4 years). At baseline, 43.0% of the sample tested positive for ethyl glucuronide, 50.9% of participants self-reported methamphetamine as their most used drug, 36.8% self-reported cannabis, and 12.3% self-reported prescription opiates as their most used drug. Among randomized participants, 47.4% tested positive for cannabis, 28.1% tested positive for methamphetamine, 16.7% tested positive for amphetamines, and 2.1% tested positive for opiates.

CONCLUSION

This is the first study to examine a culturally tailored contingency management intervention targeting co-addiction of two substances among American Indian adults. By establishing a tribal-university partnership to adapt, implement, and evaluate contingency management, we will increase the literature on evidence-based addiction treatments and research, while improving trust for addiction interventions among American Indian communities through ongoing collaboration. Moreover, results have implications for the use of contingency management as an intervention for co-addiction in any population.

Pilot investigation: randomized-controlled analog trial for alcohol and tobacco smoking co-addiction using contingency management

Contingency management (CM) is associated with decreases in off-target drug and alcohol use during primary target treatment. The primary hypothesis for this trial was that targeting alcohol use or tobacco smoking would yield increased abstinence in the opposite, nontargeted drug. We used a 2 [CM vs. noncontingent control (NC) for alcohol]×2 (CM vs. NC for smoking tobacco) factorial design, with alcohol intake (through urinary ethyl glucuronide) and tobacco smoking (through urinary cotinine) as the primary outcomes. Thirty-four heavy-drinking smokers were randomized into one of four groups, wherein they received CM, or equivalent NC reinforcement, for alcohol abstinence, smoking abstinence, both drugs, or neither drug. The CM for alcohol and tobacco group had only two participants and therefore was not included in analysis. Compared with the NC for alcohol and tobacco smoking group, both the CM for the tobacco smoking group [odds ratio (OR)=12.03; 95% confidence interval (CI): 1.50-96.31] and the CM for the alcohol group (OR=37.55; 95% CI: 4.86-290.17) submitted significantly more tobacco-abstinent urinalyses. Similarly, compared with the NC for the alcohol and tobacco group, both the CM for smoking (OR=2.57; 95% CI: 1.00-6.60) and the CM for alcohol groups (OR=3.96; 95% CI: 1.47-10.62) submitted significantly more alcohol-abstinent urinalyses. These data indicate cross-over effects of CM on indirect treatment targets. Although this is a pilot investigation, it could help to inform the design of novel treatments for alcohol and tobacco co-addiction.

Alcohol Consumption during Pregnancy: Analysis of Two Direct Metabolites of Ethanol in Meconium

Alcohol consumption in young women is a widespread habit that may continue during pregnancy and induce alterations in the fetus. We aimed to characterize prevalence of alcohol consumption in parturient women and to assess fetal ethanol exposure in their newborns by analyzing two direct metabolites of ethanol in meconium. This is a cross-sectional study performed in September 2011 and March 2012 in a series of women admitted to an obstetric unit following childbirth. During admission, socio-demographic and substance use (alcohol, tobacco, cannabis, cocaine, and opiates) during pregnancy were assessed using a structured questionnaire and clinical charts. We also recorded the characteristics of pregnancy, childbirth, and neonates. The meconium analysis was performed by liquid chromatography—tandem mass spectrometry (LC-MS/MS) to detect the presence of ethyl glucuronide (EtG) and ethyl sulfate (EtS). Fifty-one parturient and 52 neonates were included and 48 meconium samples were suitable for EtG and EtS detection. The median age of women was 30 years (interquartile range (IQR): 26–34 years); EtG was present in all meconium samples and median concentration of EtG was 67.9 ng/g (IQR: 36.0–110.6 ng/g). With respect to EtS, it was undetectable (<0.01 ng/g) in the majority of samples (79.1%). Only three (6%) women reported alcohol consumption during pregnancy in face-to-face interviews. However, prevalence of fetal exposure to alcohol through the detection of EtG and EtS was 4.2% and 16.7%, respectively. Prevention of alcohol consumption during pregnancy and the detection of substance use with markers of fetal exposure are essential components of maternal and child health.

A culturally-tailored behavioral intervention trial for alcohol use disorders in three American Indian communities: Rationale, design, and methods

BACKGROUND

Disproportionately high rates of alcohol use disorders are present in many American Indian/Alaska Native (AI/AN) communities, yet little information exists regarding the effectiveness of alcohol treatments in AI/AN populations. Contingency management is an intervention for illicit drug use in which tangible reinforcers (rewards) are provided when patients demonstrate abstinence as assessed by urine drug tests. Contingency management has not been widely studied as an intervention for alcohol problems because until recently, no alcohol biomarker has been available to adequately verify abstinence.

AIMS

The HONOR Study is designed to determine whether a culturally-tailored contingency management intervention is an effective intervention for AI/AN adults who suffer from alcohol use disorders.

METHODS

Participants include 400 AI/AN alcohol-dependent adults residing in one rural reservation, one urban community, as well as a third site to be decided, in the Western U.S. Participants complete a 4-week lead-in phase prior to randomization, then 12 weeks of either a contingency management intervention for alcohol abstinence, or a control condition where participants receive reinforcers for attending study visits regardless of alcohol use. Participants are then followed for 3-more months post-intervention. The primary study outcome is urinary ethyl glucuronide-confirmed alcohol abstinence; secondary outcomes include self-reported alcohol and drug use, HIV risk behaviors, and self-reported cigarette smoking.

DISCUSSION

This will be the largest randomized, controlled trial of any alcohol for AI/ANs and the largest contingency management study targeting alcohol use disorders, thus providing important information to AI/AN communities and the alcohol treatment field in general.

The influence of cleansing shampoos on ethyl glucuronide concentration in hair analyzed with an optimized and validated LC-MS/MS method

Ethyl glucuronide (EtG) is widely used as a marker for assessment of alcohol consumption behavior. In this study the influence of special cleansing shampoos on ethyl glucuronide concentrations in hair was investigated. For that purpose an optimized LC-MS/MS method was developed using a Hypercarb™ porous graphitic carbon (PGC) column and validated according to the guidelines of the German Society of Toxicological and Forensic Chemistry (GTFCh). Twenty-five hair samples of persons with known alcohol consumption behavior were investigated (21 positive samples and 4 blank samples). The hair samples were divided into two strands of hair and were analyzed after treatment with one out of four cleansing shampoos and without shampoo treatment. EtG concentrations in hair did not show any significant differences after a single application of the different cleansing shampoos. EtG was still detectable in all the positive hair samples without significant concentration change. These results clearly demonstrated that a single application of the tested cleansing shampoos did not remove EtG from hair and therefore had no influence on EtG concentration in analytical hair analysis.

Ethyl glucuronide and ethyl sulfate assays in clinical trials, interpretation, and limitations: results of a dose ranging alcohol challenge study and 2 clinical trials

BACKGROUND

The ethanol metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS), are biomarkers of recent alcohol consumption that provide objective measures of abstinence. Our goals are to better understand the impact of cutoff concentration on test interpretation, the need for measuring both metabolites, and how best to integrate test results with self-reports in clinical trials.

METHODS

Subjects (n = 18) were administered, 1 week apart, 3 alcohol doses calibrated to achieve blood concentrations of 20, 80, and 120 mg/dl, respectively. Urinary EtG/EtS was measured at timed intervals during a 24-hour hospitalization and twice daily thereafter. In addition, participants from 2 clinical trials provided samples for EtG/EtS and drinking histories. Cutoffs for EtG/EtS of 100/50, 200/100, and 500/250 ng/ml were evaluated.

RESULTS

Twelve hours following each challenge, EtG was always positive at the 100 and 200 cutoffs, but at 24 hours sensitivity was poor at all cutoffs following the low dose, and poor after 48 hours regardless of dose or cutoff. Similarly, in the clinical trials EtG sensitivity was good for detecting any drinking during the last 24 hours at the 2 lowest cutoffs, but under 40% during the last 24 to 48 hours. Sensitivity was reduced at the 500 ng/ml cutoff. Discrepancies between EtG and EtS were few. Comparison of self-reports of abstinence and EtG-confirmed abstinence indicated underreporting of drinking.

CONCLUSIONS

Any drinking the night before should be detectable the following morning with EtG cutoffs of 100 or 200 ng/ml. Twenty-four hours after drinking, sensitivity is poor for light drinking, but good for heavier consumption. At 48 hours, sensitivity is low following 6 drinks or less. Increasing the cutoff to 500 ng/ml leads to substantially reduced sensitivity. Monitoring both EtG and EtS should usually be unnecessary. We recommend EtG-confirmed self-reports of abstinence for evaluation of outcomes in clinical trials.

Identification and preliminary characterization of UDP-glucuronosyltransferases catalyzing formation of ethyl glucuronide

Ethyl glucuronide (EtG), a minor metabolite of ethanol, is used as a marker of alcohol consumption in a variety of clinical and forensic settings. At present there are very few studies of UDP-glucuronosyltransferases (UGT), responsible for catalyzing EtG formation, and the possible effect of nutritional components, e.g. flavonoids, which are extensively glucuronidated, on EtG formation has not been addressed at all. The following incubation conditions were optimized with regard to previously published conditions: buffer, substrate concentration, and incubation time. Isolation of EtG from the incubation mixture was also optimized. Recombinant UGT enzymes (UGT1A1, 1A3, 1A4, 1A6, 1A9, 2B7, 2B10, 2B15) were screened for their activity towards ethanol, and kinetic data were then established for all enzymes. It was decided to study the effect of the flavonoids quercetin and kaempferol on glucuronidation of ethanol. Isolation was by solid-phase extraction (SPE) to minimize matrix effects. Analysis was performed by liquid chromatography-tandem mass spectrometry (LC-MS-MS), with EtG-d5 as the internal standard. SPE was vital to avoid severe ion suppression after direct injection of the incubation solution. EtG formation was observed for all enzymes under investigation; their kinetics followed the Michaelis-Menten model, meaning the maximum reaction rate achieved at saturating substrate concentrations (V(max)) and the substrate concentration at which the reaction rate is half of V(max) (Michaelis-Menten constant, K(m)) could be calculated. The highest rate of glucuronidation was observed with UGT1A9 and 2B7. After co-incubation with both flavonoids, formation of EtG was significantly reduced for all enzymes except for UGT2B15, whose activity did not seem to be affected. Results reveal that multiple UGT isoforms are capable of catalyzing glucuronidation of ethanol; nevertheless, the effect of UGT polymorphism on glucuronidation of ethanol needs further study. Formation of EtG is inhibited by the flavonoids under investigation. Obviously, nutritional components affect conversion of ethanol to EtG. This observation may serve as a partial explanation of its variable formation in man.

Cellular photo digital breathalyzer for monitoring alcohol use: a pilot study

BACKGROUND

Monitoring alcohol use is important in numerous situations. Direct ethanol metabolites, such as ethyl glucuronide (EtG), have been shown to be useful tools in detecting alcohol use and documenting abstinence. For very frequent or continuous control of abstinence, they lack practicability. Therefore, devices measuring ethanol itself might be of interest. This pilot study aims at elucidating the usability and accuracy of the cellular photo digital breathalyzer (CPDB) compared to self-reports in a naturalistic setting.

METHOD

12 social drinkers were included. Subjects used a CPDB 4 times daily, kept diaries of alcohol use and submitted urine for EtG testing over a period of 5 weeks.

RESULTS

In total, the 12 subjects reported 84 drinking episodes. 1,609 breath tests were performed and 55 urine EtG tests were collected. Of 84 drinking episodes, CPDB detected 98.8%. The compliance rate for breath testing was 96%. Of the 55 EtG tests submitted, 1 (1.8%) was positive.

CONCLUSIONS

The data suggest that the CPDB device holds promise in detecting high, moderate, and low alcohol intake. It seems to have advantages compared to biomarkers and other monitoring devices. The preference for CPDB by the participants might explain the high compliance. Further studies including comparison with biomarkers and transdermal devices are needed.

[What ethanol metabolites as biological markers tell us about alcohol use]

Alcohol and tobacco related disorders are the two leading and most expensive causes of illness in central Europe. In addition to self reports and questionnaires, biomarkers are of relevance in diagnosis and therapy of alcohol use disorders. Traditional biomarkers such as gamma glutamyl transpeptidase or mean corpuscular volume are indirect biomarkers and are subject to influence of age, gender and non alcohol related diseases, among others.Direct ethanol metabolites such as ethyl glucuronide (EtG), ethyl sulphate (EtS) and phosphatidylethanol (PEth) are direct metabolites of ethanol, that are positive after intake of ethyl alcohol. They represent useful diagnostic tools for identifying alcohol use even more accurately than traditional biomarkers. Each of these drinking indicators remains positive in serum and urine for a characteristic time spectrum after the cessation of ethanol intake--EtG and EtS in urine up to 7 days, EtG in hair for months after ethanol has left the body. Applications include clinical routine use, emergency room settings, proof of abstinence in alcohol rehabilitation programs, driving under influence offenders, workplace testing, assessment of alcohol intake in the context of liver transplantation and fetal alcohol syndrome.

EtG/EtS in Urine from sexual assault victims determined by UPLC-MS-MS

In cases of sexual assault, victims often present too late for the detection of ethanol in biological samples. An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) method was developed and validated for the determination of ethyl glucuronide (EtG) and ethyl sulfate (EtS) in urine. Sample preparation prior to UPLC-MS-MS analysis was a simple sample dilution. The calibration ranges were 0.2-20 mg/L, and between-assay relative standard deviations were in the range of 0.7-7.0% at concentrations of 0.3, 3.0 and 7.0 mg/L. Urine samples were analyzed from 59 female patients presenting to the Sexual Assault Centre at St. Olav University Hospital in Trondheim, Norway between November 2010 and October 2011. EtG and EtS results were fully concordant, and positive in 45 of the 48 cases with self-reported alcohol intake. In contrast, ethanol was detectable in only 20 of these cases, corresponding to sensitivities of 94 and 42%, respectively. Of the patients reporting no alcohol intake, none had positive EtG/EtS findings. These data show that analysis of EtG and EtS greatly increases the detection window of alcohol ingestion in cases of sexual assault, and may shed additional light on the involvement of ethanol in such cases. The victims' self-reported intake of alcohol seems to be reliable in this study, according to the EtG/EtS findings.

Phosphatidylethanol (PEth) as a biomarker of alcohol consumption in HIV-positive patients in sub-Saharan Africa

BACKGROUND

Alcohol is heavily consumed in sub-Saharan Africa and affects HIV transmission and treatment and is difficult to measure. Our goal was to examine the test characteristics of a direct metabolite of alcohol consumption, phosphatidylethanol (PEth).

METHODS

Persons infected with HIV were recruited from a large HIV clinic in southwestern Uganda. We conducted surveys and breath alcohol concentration (BRAC) testing at 21 daily home or drinking establishment visits, and blood was collected on day 21 (n = 77). PEth in whole blood was compared with prior 7-, 14-, and 21-day alcohol consumption.

RESULTS

(i) The receiver operator characteristic area under the curve (ROC-AUC) was highest for PEth versus any consumption over the prior 21 days (0.92; 95% confidence interval [CI]: 0.86 to 0.97). The sensitivity for any detectable PEth was 88.0% (95% CI: 76.0 to 95.6) and the specificity was 88.5% (95% CI: 69.8 to 97.6). (ii) The ROC-AUC of PEth versus any 21-day alcohol consumption did not vary with age, body mass index, CD4 cell count, hepatitis B virus infection, and antiretroviral therapy status, but was higher for men compared with women (p = 0.03). (iii) PEth measurements were correlated with several measures of alcohol consumption, including number of drinking days in the prior 21 days (Spearman r = 0.74, p < 0.001) and BRAC (r = 0.75, p < 0.001).

CONCLUSIONS

The data add support to the body of evidence for PEth as a useful marker of alcohol consumption with high ROC-AUC, sensitivity, and specificity. Future studies should further address the period and level of alcohol consumption for which PEth is detectable.

A high-performance liquid chromatographic-tandem mass spectrometric method for the determination of ethyl glucuronide and ethyl sulfate in urine validated according to forensic guidelines

Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are powerful markers for alcohol intake and abuse. Several analytical procedures for the quantification of EtG and EtG in serum and urine have been developed so far. Many of the published methods show limits of detections (LODs) or limits of quantifications (LOQs) for EtG in urine within the range of 0.1 mg/L or higher. Since this is the actual cutoff value for proving abstinence in Germany, problems may occur if urine samples are highly diluted. In this paper, the validation of a highly sensitive, fast and simple LC-MS-MS for the determination of EtG and EtS in urine is described. The calibration curves for EtG and EtS is linear over the whole range (0.025-2.0 mg/L). Very low detection limits can be achieved (LOD: EtG 0.005 mg/L, EtS 0.005 mg/L; and LOQ: EtG 0.019 mg/L, EtS 0.015 mg/L). All data for selectivity, precision and accuracy, recovery, as well as for the processed sample and the freeze/thaw stability, comply with the guidelines of the German Society of Toxicological and Forensic Chemistry. Strong matrix-related effects can be compensated for by using an internal standard. Finally, the applicability of the procedure is proven by analysis of 87 human urine samples and by successful participation in interlaboratory comparison tests.

Ethyl glucuronide

Alcohol is associated with significant morbidity and mortality. Subjects abusing alcohol can be identified through clinical history, examination or self-report questionnaires. A range of biomarkers is available for detecting alcohol misuse, but there is still a need for a marker that can detect alcohol consumption in the time window between one day (ethanol) and one week (gamma-glutamyl transpeptidase and carbohydrate-deficient transferrin). Ethyl glucuronide is a direct metabolite that can be detected in urine for up to 90 h and has the potential to become a useful marker of 'binge' drinking. As a non-invasive marker, it could have a role in a variety of clinical and forensic settings.

Clinical (nonforensic) application of ethyl glucuronide measurement: are we ready?

Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are minor metabolites of ethanol. Multiple studies have documented that, depending upon the amount of alcohol consumed, they can be measured in biological fluids for hours to days after the parent compound can no longer be detected. Testing for the presence of EtG, in a manner analogous to urinary drug abuse screening, has largely been restricted to forensic and law enforcement situations. Despite a real need for an objective and possibly quantitative marker of ethanol exposure for use in conjunction with outpatient clinical trials and treatment programs, measurement of these metabolites has seen only limited clinical application. The barriers to more extensive clinical use of EtG/EtS testing, particularly misleading assay results that can occur as a consequence of inadvertent exposure to nonbeverage ethanol-containing substances, are reviewed and put into perspective. Additional information needed to develop guidelines for optimal clinical utilization of EtG/EtS measurements is discussed.

Abstinence monitoring of suspected drinking drivers: ethyl glucuronide in hair versus CDT

OBJECTIVE

Ethyl glucuronide (EtG) determinations in the hair of self-reported teetotalers were reviewed and compared with carbohydrate-deficient transferrin (CDT) blood tests (by immunochemistry and high-performance liquid chromatography [HPLC]).

METHODS

A retrospective study was carried out on 154 people whose fitness to drive had to be assessed because of the suspicion of relevant alcohol problems.

RESULTS

EtG was detected in 55 percent of the hair samples and abstinence thus disproved. In two thirds (67%) of these cases, alcohol consumption was even shown to be excessive (EtG values > 30 pg/mg). Of the EtG-positive subjects 54 and 82 percent had CDT values within the reference range by immunochemistry and HPLC, respectively. Thirty-nine percent of the EtG-negative subjects had increased immunochemical CDT values; in contrast, 96 percent had HPLC CDT values within the normal range.

CONCLUSIONS

EtG analysis in hair is a useful tool for assessing fitness to drive in suspected drinking drivers; compared to CDT values it provides a direct and unequivocal marker for reliable abstinence monitoring over a period of several months, depending on the length of the hair.

Urinary ethyl glucuronide (EtG) and ethyl sulphate (EtS) assessment: valuable tools to improve verification of abstention in alcohol-dependent patients during in-patient treatment and at follow-ups

AIMS

The aims of this study were (i) to assess the effect of additional urinary ethyl glucuronide (EtG) and ethyl sulphate (EtS) assessment on diagnosed relapse rates in detoxified alcohol-dependent patients; and (ii) to compare dropout rates between EtG- and EtS-negative and -positive patients.

DESIGN

Two studies on detoxified alcohol-dependent patients. If patients had no indication of relapse they were asked for a urinary sample at discharge from in-patient treatment 3, 6 and 12 weeks after discharge (study 1) and 1, 3 and 6 weeks after discharge (study 2), respectively.

SETTING

Department of Psychiatry, University of Luebeck, Germany.

PARTICIPANTS

A total of 107 and 32 detoxified alcohol-dependent patients having participated in a 3-week in-patient motivation enhancement programme.

MEASUREMENT

Personal interviews, breathalyzer tests, assessment of urinary EtG and EtS with liquid chromatography-tandem mass spectrometry (LC-MS/MS analysis).

FINDING

Urinary EtG and EtS were always positive at the same time. In the first study 13.5% of the patients were already positive before being discharged from hospital. At the follow-ups 3, 6 and 12 weeks after discharge 12.2, 19.4 and 28.0%, respectively, of the patients coming to the follow-up and denying relapse were positive on urinary EtG and EtS. In the second study, of those patients showing up for follow-up after 1 week and denying relapse, EtG and EtS were positive in four cases (17.4%). Only one EtG- and EtS-positive relapser (3.1%) came to the next follow-ups. In both studies the rates of detected relapses were significantly higher for early follow-ups if urinary EtG and EtS results were considered additionally. Dropout rates until the next follow-up were significantly higher among positive than EtG- and EtS-negative patients.

CONCLUSION

Urinary EtG and EtS improve verification of abstinence in studies of alcohol-dependent patients.

Assessment of alcohol consumption among hepatitis C-positive people receiving opioid maintenance treatment using direct ethanol metabolites and self-report: a pilot study

This study was conducted to identify the alcohol consumption among hepatitis C-positive people receiving opioid maintenance therapy using self-report and biomarkers. A total of 49 people (28 male, 21 female) were hepatitis C virus (HCV) positive and were included. The alcohol use disorder identification test (AUDIT) and self-reported ethanol intake in the last 28 days were assessed. In addition to gamma-glutamyl-transferase (GGT) and mean corpuscular volume (MCV), ethyl glucuronide (EtG) and ethyl sulphate (EtS) were determined in serum and urine (UEtG, UEtS, SEtG) using liquid chromatography/tandem mass-spectroscopy (LC/MS-MS) with deuterated internal standards. Abstinence from alcohol was reported for the last 28 days by 13 participants and for the last 7 days by 22. AUDIT was > 8 in 27 cases. The maximum values were 34.8 mg/l for UEtG, 5.3 mg/l for UEtS and 0.15 for SEtG. Among the 19 UEtG positives, 8 had not reported any ethanol intake in the 7 days prior to the study. Six participants reported intake of up to 320 g of ethanol in the last 7 days, but were negative for SEtG, UEtG and UEtS. Self-reported ethanol intake in the last 28 days correlated with AUDIT score (r = 0.733, P < 0.001), with the direct ethanol metabolites and MCV. In this population, abstinence and episodic heavy drinking are more common than in the general population. Episodic heavy drinking is a significant cause of acute risk in this population. Results from biomarker testing could indicate cases of under- as well as over-reporting of alcohol consumption. Further research on the diagnostic accuracy of direct ethanol metabolites, including the use of phosphatidylethanol (PEth), in this setting is needed.

Kinetics in serum and urinary excretion of ethyl sulfate and ethyl glucuronide after medium dose ethanol intake

The direct ethanol metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS), are of increasing importance for clinical and forensic applications, but there are only few studies on the kinetics of EtG in serum and none on EtS. In this study, 13 volunteers (social drinkers) drank ethanol in the form of white wine to reach a blood alcohol concentration of 0.51 +/- 0.17 g/kg, and blood and urine samples were analyzed for EtG and EtS simultaneously by chromatography-tandem mass spectrometry (LC-MS/MS). Mean peak serum EtG and EtS concentrations were 2.9 +/- 1.3 and 2.8 +/- 1.6 micromol/l, respectively, and were reached between 4.0 +/- 0.9 h after the start of drinking (3.0 +/- 0.5 h for EtS). The mean time differences between reaching maximum blood ethanol levels and serum metabolite levels were 2.3 +/- 0.9 h for EtG and 1.2 +/- 0.5 h for EtS. In the last blood samples collected (10-11 h after the start of drinking), 11 (of 13) volunteers were still positive for EtG in serum, whereas only 2 were positive for EtS. In the serum of one female person, no EtS was detectable at any time; however, it was excreted in the urine in (low) concentrations. Ethanol was detectable in the serum for up to 8.6 h after the start of drinking, whereas EtG and EtS were detectable up to more than 5.8 h (EtG) and 4.0 h (EtS), respectively. Mean peak urinary concentrations were 401 +/- 232 micromol/l for EtG and 266 +/- 153 micromol/l for EtS, and mean peak levels were reached 6.2 +/- 0.9 h (EtG) and 5.3 +/- 1.2 h (EtS) after the start of drinking. Maximum concentrations of EtG and EtS in serum showed a wide interindividual variation and could not be correlated to the maximum blood ethanol concentrations. Correlations (p < 0.001, Kendall's Tau b) were found when comparing pairs of parameters, but mostly involved areas under the curve (AUC) of metabolites or of ethanol; one correlation linked the peak concentrations of EtG and EtS in urine.

Determination of glucuronidated 5-hydroxytryptophol (GTOL), a marker of recent alcohol intake, by ELISA technique

OBJECTIVES

To compare markers of alcohol consumption.

DESIGN AND METHODS

Measurement of urinary ethyl glucuronide, 5-hydroxytryptophol, 5-hydroxytryptophol glucuronide, 5-hydroxyindole acetic acid in 10 patients during alcohol withdrawal.

RESULTS

5-Hydroxytryptophol glucuronide was measured by ELISA with good analytical precision, its diagnostic specificity and sensitivity was better than that of 5-hydroxytryptophol and its correlation was closer to ethyl glucuronide than to 5-hydroxytryptophol.

CONCLUSION

Determination of 5-hydroxytryptophol glucuronide by ELISA offers promising results in detection of previous alcohol consumption.

Taking account of cultural and societal influences on substance use diagnoses and criteria

AIMS

This article reviews the problems of cross-cultural applicability, which have been identified at the level of instrument items, at the level of criteria, and at the level of concepts and diagnoses. One near-universal appears to be that the diagnoses carry a weight of moral judgement and often of social stigma, whatever the clinician's intentions.

METHODS

The findings of studies on variations between cultures in the meaningfulness and meaning of the main substance use diagnoses and criteria are described.

RESULTS

Suggestions are made for directions of thinking and work to improve the cross-cultural applicability of five current diagnoses: intoxication, withdrawal, harmful use, abuse and dependence.

CONCLUSIONS

It is argued that the possibility should be held open of bounded applicability of some diagnoses or criteria, in some societies but not in others.

Ethyl sulphate: a direct ethanol metabolite reflecting recent alcohol consumption

BACKGROUND

Ethyl sulphate (EtS), a direct ethanol metabolite, appears to offer potential as a biomarker for recent alcohol consumption. Although its window of assessment is similar to that of ethyl glucuronide (EtG), there are differences between the two markers in their pathways for formation and degradation.

AIMS

(a) To assess the excretion of EtS compared to EtG and ethanol in drinking experiments with healthy volunteers, and (b) to elucidate the possibility of using the two metabolites for monitoring abstinence in substance use disorder patients during rehabilitation treatment.

DESIGN, SETTING, PARTICIPANTS

(a) Nine drinking experiments were performed by six healthy volunteers (two females, four males), with a mean age of 34.1 years (20-62), average oral intake of 0.2 g/kg ethanol (0.1-0.61), and having 74 spot urine samples. (b) Thirty-six substance abuse patients (mean age 41.9 years, 20-59; 22 males, 14 females) in a rehabilitation programme after withdrawal, producing 98 urine samples. Ethyl glucuronide and ethyl sulphate were measured using liquid chromatography tandem mass spectrometry (LC-MS/MS) using d5-EtG and d5-EtS, respectively, as an internal standard.

FINDINGS

(a)

VOLUNTEERS

EtG and EtS were detectable for up to 36 hours and reached the limits of determination in urine at 20.6 hours and 21.2 hours (median), respectively, after ethanol intake. EtG-100 (standardized to a creatinine of 100 mg/dl) reached its maximum level at 2.8 hours and EtS-100 at 2.1 hours (median) after the beginning of the experiment. Of the ethanol ingested, 0.022% was excreted as EtS in one volunteer. Eight samples were positive for EtS only and six for EtG only. Spearman's rank correlation coefficients of 0.84 (P < 0.0001) between EtG and EtS and 0.87 (P < 0.0001) between EtG-100 and EtS-100 were found. (b)

PATIENTS

of the 98 urine samples evaluated, 27 were positive for EtS and of these only 20 were also positive for EtG. Spearman's rank correlation coefficients of 0.84 (P < 0.0001) between EtG and EtS and 0.82 (P < 0.0001) between EtG-100 and EtS-100 were found.

CONCLUSIONS

The data from patients and volunteers suggest that the direct ethanol metabolite ethyl sulphate has the potential to serve as a biomarker of recent ethanol intake. Because EtG and EtS are formed via different pathways they might be used conjointly, thereby increasing sensitivity.

Detection of Recent Ethanol Intake With New Markers: Comparison of Fatty Acid Ethyl Esters in Serum and of Ethyl Glucuronide and the Ratio of 5-Hydroxytryptophol to 5-Hydroxyindole Acetic Acid in Urine

BACKGROUND

At present, recent ethanol consumption can be routinely detected with certainty only by direct measurement of ethanol concentration in blood or urine. Because ethanol is rapidly eliminated from the circulation, however, the time span for this detection is in the range of hours. Several new markers have been proposed to extend the detection interval, but their characteristics have not yet justified their use in routine clinical practice. We therefore investigated three new markers and compared their kinetics and sensitivities: (1) fatty acid ethyl esters (FAEEs) in serum, (2) ethyl glucuronide (EtG) in urine, and (3) the ratio of 5-hydroxytryptophol to 5-hydroxyindole acetic acid (5-HTOL/5-HIAA) in urine.

METHODS

Seventeen healthy men participated in a drinking experiment. Blood and urine samples were collected twice daily on three consecutive days and once daily on days 4 and 5. Ethanol concentration was determined by gas chromatography, FAEE levels, by gas chromatography with mass spectrometry, EtG concentration, by liquid chromatography-tandem mass spectrometry, and 5-HTOL/5-HIAA ratio, by high-performance liquid chromatography.

RESULTS

The peak serum ethanol concentrations of the subjects ranged from 5.4 to 44.7 mmol/liter (mean +/- SD, 30.1 +/- 9.1 mmol/liter). In the case of the serum ethanol determination, 100% sensitivity was reached only immediately after the end of the drinking experiment, and in the case of FAEE levels and 5-HTOL/5-HIAA ratio, it tested for 6.7 hr after the end of the ethanol intake. Thereafter, these latter parameters declined until 15.3 hr (FAEEs) and 29.4 hr (5-HTOL/5-HIAA), subsequently remaining in a stable range until 78.5 hr without further decrease. In contrast, EtG concentration showed 100% sensitivity until 39.3 hr and thereafter decreased, falling to below the limit of quantification of 0.1 mg/liter at 102.5 hr.

CONCLUSION

After moderate drinking, EtG in the urine proved to be a superior marker of recent ethanol consumption in healthy subjects. This is because EtG is a direct ethanol metabolite, it occurs in the urine only when ethanol has been consumed, and its sensitivity remains at the level of 100% for 39.3 hr.

Assessment of UDP-glucuronosyltransferase catalyzed formation of ethyl glucuronide in human liver microsomes and recombinant UGTs

While ethanol is primarily metabolized to acetaldehyde and acetic acid via alcohol dehydrogenase, a minor but increasingly important pathway in the field of forensic science involves the conjugation of glucuronic acid to form an ethyl glucuronide (EtG) metabolite. The kinetics of ethyl glucuronide formation were examined in human liver microsomes (HLM) and recombinant UDP-glucuronosyltransferases (UGTs). The metabolite exhibited a relatively slow rate of formation in a human liver microsome mix of 75.4 pmol/(min/mg). Further investigation identified multiple UGT isoforms to be responsible for catalyzing the addition of glucuronic acid to ethanol, with UGT1A1 and 2B7 being the two most prevalent isoforms. Co-incubation with bilirubin or 3'-azido-3'-deoxythymidine (UGT1A1 and 2B7 inhibitors, respectively) inhibited the greatest amount of ethyl glucuronide formation, though other UGT inhibitors also showed some effect. Enzyme kinetics were performed in human liver microsomes and recombinant UGT enzymes. The apparent Km (Km app) and Vmax values were determined to be 0.17+/-0.08 mM and 75.98+/-5.63 pmol/(min/mg) (human liver microsomes), 0.03+/-0.01 mM and 25.22+/-3.45 pmol/(min/mg) (UGT1A1), and 0.11+/-0.04 mM and 52.03+/-9.8 pmol/(min/mg) (UGT2B7). Thus, it appears that multiple UGTs are responsible for the formation of ethyl glucuronide and that any functional differences in the enzymology underlying ethyl glucuronide formation would most likely be masked by a combination of other enzymatic pathways.

Formation of ethyl nitrite in vivo after ethanol administration

The purpose of the current study was to ascertain whether ethyl nitrite could be detected in vitro from the reaction of ethanol with peroxynitrite, as well as after administration of ethanol to mice. Ethyl nitrite analyte was determined by using gas chromatography--mass spectrometry with headspace analysis with the use of a solid-phase microextraction device. Peroxynitrite was allowed to react with ethanol under a variety of conditions in vitro. Ethyl nitrite was generated when peroxynitrite was allowed to react with ethanol. Male, inbred short-sleep mice were injected intraperitoneally with either ethanol [5.2 g/kg; 15.0% (weight/volume) ethanol in saline] or a 50:50 mixture of deuterium-labeled ethanol (D5-ethanol) and ethanol. Blood samples, as well as whole brain and liver sections, were obtained from mice 30 min later for determination of ethanol, D5-ethanol, ethyl nitrite, and deuterium-labeled ethyl nitrite (D5-ethyl nitrite). Time courses for the appearance of ethyl nitrite in blood samples, as well as in whole brain and liver sections, obtained from mice were carried out. After ethanol administration, ethyl nitrite was detected and quantitated in mouse blood, brain, and liver. A small fraction of ethyl nitrite was present. When a 50:50 mixture of ethanol and D5-ethanol was given to animals, both ethyl nitrite and D5-ethyl nitrite were found in blood and brain in approximately the same ratio as that of ethanol and D5-ethanol. The level of D5-ethyl nitrite in liver was more than twice that of ethyl nitrite, indicating a possible isotope effect in the metabolism of ethyl nitrite. Ethyl nitrite is a new metabolite of ethanol in vivo. The mechanism of ethyl nitrite formation is most likely the reaction of ethanol with peroxynitrite generated in vivo from nitric oxide.

Ethyl glucuronide: a biomarker to identify alcohol use by health professionals recovering from substance use disorders

AIMS

Physicians recovering from substance-related disorders are usually allowed to return to practice if they agree to remain abstinent from drugs, including alcohol, and to undergo random urine testing. Over 9000 physicians are currently involved in such monitoring programs in the US. To date, it has been difficult to adequately monitor abstinence from alcohol due to the short half-life of alcohol and no other highly specific marker. Ethyl glucuronide (EtG), a direct metabolite of alcohol, offers an extended window for assessment of drinking status (up to 5 days). Our aim was to assess the potential value of EtG testing in abstinence-based monitoring programs.

PATIENTS AND METHODS

Urine samples were obtained from 100 participants in a physician monitoring program and additional samples were subsequently obtained 'for cause', 'to verify positive urine alcohol, when drinking was denied' and 'in high risk individuals'. All participants had signed contracts agreeing to remain abstinent from mood-altering drugs, including alcohol, and had agreed to random urine testing. EtG was determined using LC/MS-MS in addition to standard testing. The main outcome measure were urine specimens positive for EtG versus those positive based on standard testing for alcohol and other drugs.

RESULTS

Among the initial 100 random samples collected, no sample was positive for alcohol using standard testing; however, seven were positive for EtG (0.5-196 mg/l), suggesting recent alcohol use. Subsequent EtG testing was performed clinically during the course of monitoring. Of the 18 tests performed to date, eight of eight tests performed 'for cause' were positive for EtG but negative for all other drugs including urine alcohol. All eight were confirmed positive by self reported drinking by the patient when confronted regarding the positive test result. Of six tests performed to 'confirm a positive urine alcohol' two were positive for EtG and confirmed positive by self reported drinking. For the other four samples, especially as two are from a diabetic, in vitro fermentation of ethanol is discussed.

CONCLUSIONS

These data suggest that physicians in monitoring programs have a higher rate of unrecognized alcohol use than previously reported. Incorporation of EtG testing into alcohol abstinence monitoring can strengthen these programs.

On Sensitivity, Specificity, and the Influence of Various Parameters on Ethyl Glucuronide Levels in Urine???Results From the WHO/ISBRA Study

BACKGROUND

Ethyl glucuronide (EtG), a direct ethanol metabolite, seems to meet the need for a sensitive and specific marker for monitoring recent alcohol consumption in different settings. Our aim was to study sensitivity, specificity, and the influence of various parameters on EtG levels in urine.

PATIENTS AND METHODS

Urine samples for a total of 453 patients (373 male, 80 female) were statistically analyzed. The mean age was 37.1 years (median 36, SD 12.59), body mass index was 24.7, total ethanol consumed last month was 1817.66 g (each median), and 80 patients reported cannabis use within the last 30 days. Determination of EtG was performed with a liquid chromatography-tandem mass spectrometry method with deuterium-labeled EtG as internal standard.

RESULTS

For EtG in urine, a good correlation was found with other state markers and days of sobriety. In a regression analysis, age, gender, marijuana use, kidney disease, and total grams of ethanol consumed last month were the variables that significantly influenced EtG levels in contrast to race, smoking, body mass index, cirrhosis of liver, age began drinking regularly, packs of cigarettes smoked last month, and total body water. Furthermore, in a receiver operating characteristic curve analysis to distinguish between nondrinkers and individuals sober > 4 days versus individuals drinking in the recent 4 days, area under the curve was 0.834. At a cutoff of 0.145 mg/liter, sensitivity was 83.5% and specificity 68.3%. A receiver operating characteristic curve was calculated for lifetime alcohol abuse or dependence against those who had never been abusers or dependent. In this case, subjects were either never dependent or lifetime dependent, but those currently dependent were excluded. The resulting area under the curve was 0.694. At a cutoff of 0.145 mg/liter, sensitivity was 73.8% and specificity 60.3%. For those with a self-reported sobriety of less than 24 hr, the area under the curve was 0.899, sensitivity was 90.8%, and specificity was 76.5% at a cutoff of 0.435 mg/liter when we calculated nondrinkers and light drinkers against heavy drinkers and drinkers needing treatment. Cannabis-using patients showed significant differences with regard to almost all state markers when compared with nonconsuming subjects.

CONCLUSIONS

Age, gender, marijuana use, kidney disease, and total grams of ethanol consumed last month should be taken into consideration when interpreting results of EtG in urine. Sensitivity and specificity seem promising. Cannabis use can be regarded as an indicator for other serious mental problems in alcohol-using subjects.

Confirmatory analysis of ethylglucuronide in urine by liquid-chromatography/electrospray ionization/tandem mass spectrometry according to forensic guidelines

beta-D-ethylglucuronide (EtG) is a stable Phase II metabolite of ethanol which can be detected in urine samples several days after elimination of ethanol. It is a useful diagnostic parameter for monitoring abstinence of alcoholics in alcohol withdrawal treatment. For this purpose, determination in urine is mainly performed by LC-MS, LC-MS/MS, or by GC-MS. For the mass spectrometric identification and detection of controlled substances in more sensitive fields such as forensic toxicology, workplace drug testing, doping analysis, and veterinary organic residue control, official guidelines have been released requiring a chromatographic separation and a minimum of two mass spectrometric transitions of the analyte. However, for detection of EtG none of the published LC-MS/MS methods could fulfill the minimum requirements of any of these guidelines. Therefore, an existing LC-MS/MS method has been modified by monitoring further MS/MS transitions instead of only one (deprotonated molecule [M - H](-)/product ions: m/z 75, 85, 113, and 159 optional) with the aim of withstanding administrative or court scrutiny in forensic or workplace drug testing cases. Full method validation has been performed in accordance to guidelines of the German Society of Toxicology and Forensic Chemistry (GTFCh) and requirements of ISO 17025. One application field in the United States is a workplace monitoring program to detect surreptitious alcohol use among recovering health professionals, who by contract had agreed on total abstinence after drug and alcohol withdrawal therapy.

Ethyl glucuronide--the direct ethanol metabolite on the threshold from science to routine use

AIMS

Current biological state markers remain suboptimal with regard to sensitivity and specificity for monitoring recent alcohol consumption in various settings. Furthermore, these biomarkers can be influenced by age, gender and a variety of substances and non-alcohol-associated diseases and do not cover fully the time axis for alcohol intake. Ethyl glucuronide (EtG) is a non-volatile, water-soluble, stable, direct metabolite of ethanol that can be detected in various body fluids, tissues and hair. Shortly after the consumption even of small amounts of ethanol, EtG becomes positive. It can detect ethanol intake up to 80 hours after the complete elimination of alcohol from the body, covering a unique and important time spectrum for recent alcohol use. EtG seems to meet the need for a sensitive and specific marker to elucidate alcohol use not detected by standard testing.

DESIGN, SETTING, PARTICIPANTS, METHODS AND FINDINGS

The literature was reviewed with a focus on possible diagnostic and therapeutic applications, currently available methods and future perspectives. To date, more than 4000 samples of body fluids, tissues and hair from approximately 1500 individuals have been assessed.

CONCLUSIONS

The data suggest that EtG is a useful tool in numerous settings, including alcohol and drug treatment (to detect lapse/relapse and for motivational feedback), in safety sensitive work settings where use is dangerous or in other settings where alcohol use may be risky (e.g. such as driving, work-place, pregnancy or monitoring physicians or other professionals who are in recovery and working) or for resolving forensic questions. If the question of recent alcohol consumption has to be answered in a binary way (yes/no), such as for determining lapses. the use of EtG in urine is among the preferred tests. The use of this marker alone and complementary with other biological state markers and self-reports is expected to lead to significant improvement in treatment outcome, therapy efficacy and cost reduction.

Ethyl glucuronide discloses recent covert alcohol use not detected by standard testing in forensic psychiatric inpatients

BACKGROUND

Considerable lives and money could be saved if one could detect early stages of lapsing/relapsing behavior in addicted persons (e.g., in safety-sensitive workplaces) and could disclose harmful drinking in social drinkers. Due to the serious public health problem of alcohol use and abuse worldwide, markers of alcohol use have been sought. Both ethyl glucuronide (EtG) and phosphatidyl ethanol (PEth) appear to have high sensitivity and specificity and a time frame of detection that may elucidate alcohol use not detected by standard testing. Our aim was to assess their potential for detecting recent covert alcohol use under controlled conditions.

METHODS

Thirty-five forensic psychiatric inpatients in a closed ward who had committed a substance-related offense ( section sign 64 StGB), were followed for 12 months. The complete time spectrum of possible alcohol consumption was covered by the complementary use of breath and urinary ethanol (hours), urinary EtG (days), %carbohydrate-deficient transferrin (CDT)/PEth (weeks), and gamma-glutamyltranspeptidase (GGT)/mean corpuscular volume (MCV) (weeks-months).

RESULTS

Fourteen of the 146 urine samples examined were positive for EtG. In all EtG-positive cases, patients reported alcohol consumption of between 40 and 200 g of ethanol 12-60 hr prior to testing. Urinary and breath ethanol were positive in only one case. In the blood samples, PEth was not positive in any case and %CDT did not exceed the reference value. Isoelectric focusing showed no abnormal Tf subtypes.

CONCLUSIONS

The findings emphasize the diagnostic and therapeutic usefulness, specificity, and sensitivity of EtG as a marker of recent alcohol use. Such a test is needed in numerous settings, including alcohol and drug treatment (to detect lapse/relapse), in safety-sensitive work settings where use is dangerous or in other settings where use may be inappropriate (e.g., such as driving, workplace, pregnancy, or monitoring physicians or other professionals who are in recovery and working), or for testing other groups (such as children or those with medical problems) where alcohol use would be unhealthy or unsafe. The health, social and socioeconomic benefits arising from the future use of these markers is hard to overestimate.