Prolonged Urinary Detection Times of EtG and EtS in Patients with Decreased Renal Function

Role of Biomarkers to Assess the Use of Alcohol

Alcohol-associated liver disease has seen a significant rise in the last 2 decades, with an associated rise in the need for accurate alcohol use assessment. Alcohol use has been associated with poor outcomes in both the pre-liver transplant and post-liver transplant patients. Patients with alcohol use disorder often under-report their alcohol consumption because of varying factors, highlighting the need for objective assessment of alcohol use. Aside from the available self-report questionnaires, multiple serologic biomarkers are currently available to assist clinicians to assess recent alcohol consumption among patients with chronic liver disease, liver transplant candidates, and recipients. In this review, we will assess some of these alcohol biomarkers, discuss their strengths and weakness, and review-available data to discuss their role in pre-liver transplant and post-liver transplant population.

EtG Quantification in Hair and Different Reference Cut-Offs in Relation to Various Pathologies: A Scoping Review

Ethyl glucuronide (EtG) is a non-volatile, non-oxidative, hydrophilic, and stable ethanol phase II metabolite. EtG is produced through ethanol glucuronidation by UDP-glucuronosyltransferase (UGT), a phase II enzyme. EtG can be extracted from different biological matrices, including keratin ones, such as hair or nails. The purpose of this scoping review is to describe the relationship between EtG levels in hair and some of the most common and frequent pathological conditions and verify whether different reference cut-offs in relation to various pathologies have been identified in the scientific literature. In fact, in-depth knowledge of the influence of pathologies, such as diabetes mellitus, hepatic and renal dysfunction, on EtG production and its storage in keratin matrices would allow a more appropriate interpretation of obtained data and rule out false positives or false negatives. This scoping review is based on bibliographic research carried out on PubMed regarding the quantification of EtG in hair of subjects affected by different pathological conditions. According to the scientific literature, the main and most common pathologies that can affect the concentration of EtG in hair are liver and kidney diseases and diabetes. The EtG quantification analytical data should be interpreted carefully as they may have a great impact in both forensic and clinical contexts.

Ethyl glucuronide in hair detects a high rate of harmful alcohol consumption in presumed non-alcoholic fatty liver disease

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) and alcohol-related liver disease (ALD) cannot reliably be distinguished by routine diagnostics, and the role of alcohol consumption in metabolic dysfunction-associated fatty liver disease (MAFLD) remains unclear. We investigated alcohol consumption in patients with presumed NAFLD and ALD using novel objective alcohol markers.

METHODS

In total, 184 consecutive patients were included in this prospective observational study. Alcohol intake was assessed by ethylglucuronide in hair (hEtG) and urine (uEtG); the utility of these measures for alcohol detection was compared to Alcohol Use Disorders Identification Test-Consumption (AUDIT-C), carbohydrate deficient transferrin (CDT), mean corpuscular volume (MCV), gamma-glutamyltransferase (GGT), and ALD/NAFLD index (ANI). Clinical characteristics of patients with NAFLD and ALD were re-assessed after reclassification based on repeated moderate (≥10 g <60 g EtOH/day) and excessive (≥60 g EtOH/day) alcohol consumption, and patients were retrospectively reclassified based on MAFLD criteria.

RESULTS

Repeated moderate to excessive alcohol consumption was detected in 28.6%, 28.5%, and 25.0% of patients with presumed NAFLD, ALD or MAFLD, respectively. ANI score, AUDIT-C, uEtG, and hEtG showed AUCs of 0.628, 0.733, 0.754, and 0.927 for the detection of repeated moderate to excessive alcohol consumption, respectively. The indirect markers CDT, MCV and GGT were not reliable. Patients with repeated moderate or excessive alcohol consumption were significantly more often male, had a significantly lower BMI, and suffered significantly less often from type 2 diabetes or impaired glucose tolerance.

CONCLUSIONS

In total, 28.6% of patients with presumed NAFLD, and 25.0% with MAFLD are at risk of alcohol-related liver damage. AUDIT-C, uEtG and hEtG should be used to screen for alcohol consumption in patients with fatty liver disease.

LAY SUMMARY

Fatty liver disease can be caused by metabolic factors and/or alcohol consumption. The diagnosis of non-alcoholic fatty liver disease (NAFLD) is based on the exclusion of harmful alcohol consumption, while metabolic dysfunction-associated fatty liver disease (MAFLD), which has been proposed as a new name for NAFLD, is based on the presence of metabolic comorbidities and allows for alcohol consumption. Herein, we show that up to 29% of patients diagnosed with NAFLD and 25% with MAFLD are at risk of alcohol-related liver damage. We show that ethyl glucuronide (a metabolite of alcohol) in the hair and urine can accurately detect potentially harmful alcohol consumption in these patients - as such, these tests should be integrated into routine diagnostic work-up for patients with fatty liver disease.

Ethyl Glucuronide and Ethyl Sulphate in Urine: Caution in their use as markers of recent alcohol use

AIM

To clarify the role of the ethanol metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS), in monitoring alcohol consumption.

METHOD

We recruited 7 female and 17 male volunteers who were instructed to consume a quantity of beer (containing 48 gm ethanol) with food in one session. We examined urinary excretion of EtG and EtS over time and looked for correlations between the concentrations of the metabolites EtG and EtS.

RESULTS

EtG concentrations in urine varied between 0.026 and 430.372 μg/ml with average values between 11.85 μg/ml (SD 19.75), 30 min after alcohol intake, and 100.39 μg/ml (SD 101.34), 4.5 h after alcohol intake. EtS urinary concentration ranged from 0.006 to 101.432 μg/ml with average values between 4.77 μg/ml (SD 5.42), 30 min after alcohol intake, and 30.14 μg/ml (SD 27.20), 4.5 h after alcohol intake. Spearman's test showed that urinary EtG and EtS correlated significantly at several time points.

CONCLUSION

The great interindividual variability in their excretion suggests caution in the use of urinary measurement of these metabolites in forensic investigations.

Challenges of LC-MS/MS ethyl glucuronide analysis in abstinence monitoring of liver transplant candidates

Background Urinary ethyl glucuronide (EtG) has emerged as the biomarker of choice for alcohol abstinence monitoring in forensic toxicology and is now used in the listing decision process for liver transplantations (LTs) in the German transplant program. However, EtG analysis in this patient group is challenging due to severely impaired liver function, renal failure, co-morbidities and multidrug regimens. The aim of our study was to evaluate liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based EtG analysis for a precise abstinence monitoring in transplant candidates. Methods EtG and ethyl sulfate (EtS) were analyzed by a commercial LC-MS/MS assay in 1787 spot urine samples of 807 patients (>85% from the Department of Hepatology) using a combination of quantifier and two qualifier mass transitions for each analyte. Influences of bacterial contamination, kidney and liver function were investigated. Results Two hundred and sixty-four urine samples had elevated (≥0.5 mg/L) EtG concentrations when only analyzing one quantifier mass transition. Eleven results (4.2%) were found to be false positive after combining three mass transitions for EtG quantification and verification with parallel analysis of EtS. Decreased kidney function was associated with a significantly higher rate of positive EtG samples. One of the false positive results was caused by bacterial metabolism. Conclusions Multimorbid pre-transplant patients have a high risk of individual analytical disturbances of EtG results obtained by LC-MS/MS. Therefore, EtG and EtS should always be measured by a combination of one quantifier and two qualifiers each and evaluated together.

Confronting the Crisis of Comorbid Alcohol Use Disorder and Alcohol-Related Liver Disease With a Novel Multidisciplinary Clinic

BACKGROUND

Alcohol-related liver disease (ALD) is prevalent and deadly and increasingly affects younger people and women. No single discipline is adequately equipped to manage its biopsychosocial complexity.

OBJECTIVES

Depict the scope of the ALD problem, provide a narrative review of other integrated care models, share our experience forming and maintaining a multidisciplinary ALD clinic for over a year, and provide recommendations for replication elsewhere.

METHODS

Critical evaluation of clinic implementation and its first year of operation.

RESULTS

The clinical rationale for multidisciplinary ALD treatment is clear and supported by the literature. Such models are feasible although surprisingly rare and vulnerable to various surmountable challenges.

CONCLUSIONS

Successful ALD clinics must be built by teams with solid personal and professional relationships, supported by institutional leadership, and must use a new kind of multidisciplinary paradigm and training. Consultation-liaison psychiatry is uniquely positioned to lead future efforts in the care and study of ALD.

Ethyl glucuronide hair testing: A review

Ethyl glucuronide (EtG) is a minor, non-oxidative ethanol metabolite that can be detected in several matrices (e.g. blood, urine, hair, meconium) for variable periods of time. Quantification of EtG in hair (hEtG) has established itself, over recent years, as one of the most reliable biomarkers of long-term alcohol consumption habits, with the Society of Hair Testing (SoHT) offering cut-off values for assessment of both abstinence and heavy drinking (>60 g/day). Despite its high diagnostic performance, however, issues concerning inter- and intra-laboratory variability as well as data interpretation are still being investigated and represent the ultimate barrier to widespread acceptance of hEtG in the forensic context. The aim of this review is to summarize currently available analytical methods of hEtG testing, provide a framework to understand current hEtG cut-offs and their possible upcoming changes (in particular, a lower abstinence cut-off has been proposed for the 2019 revision of the SoHT consensus), and offer a schematic but exhaustive overview of the pitfalls in result reproducibility and interpretation that may limit applications of hEtG testing in the forensic context. Ultimately, the purpose of the authors is not to undermine the reliability of hEtG as an alcohol use marker, but rather to enhance it by promoting familiarization with all aspects related to it, from ethanol pharmacokinetics and EtG incorporation into hair, to sample preparation and analytical methods, to specific cases warranting close attention and additional tests for correct interpretation of hEtG results.

Alcohol Use Disorders in Alcoholic Liver Disease

Alcohol use disorder (AUD) is common in alcoholic liver disease (ALD) and intrinsic to its pathophysiology. Optimal treatment requires a multidisciplinary team approach and a working alliance between patients and providers. Diagnosing AUD involves a combination of thorough history taking, physical examination, screening questionnaires, and alcohol biomarkers. Alcohol biomarkers have advantages and limitations of use of which clinicians should be aware. AUD treatment is effective, multifaceted, and can be tailored to each individual. Available treatment modalities are myriad: motivational enhancement therapy, cognitive behavior therapy, 12-step facilitation, group therapies, intensive outpatient programs, inpatient and residential treatment, and relapse prevention medications.

Cut-Point Levels of Phosphatidylethanol to Identify Alcohol Misuse in a Mixed Cohort Including Critically Ill Patients

BACKGROUND

Although alcohol misuse is associated with deleterious outcomes in critically ill patients, its detection by either self-report or examination of biomarkers is difficult to obtain consistently. Phosphatidylethanol (PEth) is a direct alcohol biomarker that can characterize alcohol consumption patterns; however, its diagnostic accuracy in identifying misuse in critically ill patients is unknown.

METHODS

PEth values were obtained in a mixed cohort comprising 122 individuals from medical and burn intensive care units (n = 33), alcohol detoxification unit (n = 51), and healthy volunteers (n = 38). Any alcohol misuse and severe misuse were referenced by Alcohol Use Disorders Identification Test (AUDIT) and AUDIT-C scores separately. Mixed-effects logistic regression analysis was performed, and the discrimination of PEth was evaluated using the area under the receiver-operating characteristic (ROC) curve.

RESULTS

The area under the ROC curve for PEth was 0.927 (95% CI: 0.877, 0.977) for any misuse and 0.906 (95% CI: 0.850, 0.962) for severe misuse defined by AUDIT. By AUDIT-C, the area under the ROC curves was 0.948 (95% CI: 0.910, 0.956) for any misuse and 0.913 (95% CI: 0.856, 0.971) for severe misuse. The PEth cut-points of ≥250 and ≥400 ng/ml provided optimal discrimination for any misuse and severe misuse, respectively. The positive predictive value for ≥250 ng/ml was 88.7% (95% CI: 77.5, 95.0), and the negative predictive value was 86.7% (95% CI: 74.9, 93.7). PEth ≥ 400 ng/ml achieved similar values, and similar results were shown for AUDIT-C. In a subgroup analysis of critically ill patients only, test characteristics were similar to the mixed cohort.

CONCLUSIONS

PEth is a strong predictor and has good discrimination for any and severe alcohol misuse in a mixed cohort that includes critically ill patients. Cut-points at 250 ng/ml for any, and 400 ng/ml for severe, are favorable. External validation will be required to establish these cut-points in critically ill patients.

[New biomarkers for assesing alcohol consumption]

Alcohol abuse has significant medical, social and socioeconomic consequences. Alcohol biomarkers may serve as a useful tool in identifying individuals with excessive alcohol consumption in medical as well as medico-legal contexts.

Evaluation of the hip-flask defence by determination of ethyl glucuronide and ethyl sulphate concentrations in blood

INTRODUCTION

The hip-flask defence (i.e. claiming ethanol intake after an incident) is difficult to refute by the use of ethanol analyses alone, as these may show decreasing concentrations shortly after intake of alcohol. The non-oxidative metabolites of ethanol, ethyl glucuronide (EtG) and ethyl sulphate (EtS) have a different pharmacokinetic profile, with peak concentrations in blood around 4h after intake. The aim of this study was to describe a method for using EtG-analysis for the purpose of estimating the time point of ethanol intake and to report cases in which this method is used.

METHODS

Previously published studies are summarised. Also, in expert witness cases where the hip-flask defence is claimed, EtG and EtS were analysed in selected cases. Twelve such cases are reported.

RESULTS

In previous studies, about 70 healthy volunteers have been included in different kinetic studies, demonstrating maximal individual concentrations of EtG always below 0.5 mg/L after 1 h, below 1 mg/L after 2 h and somewhat above 1 mg/L 4 h after a moderate alcohol intake (up to 80 grams of ethanol). Twelve cases are reported in the present study, where the suspect claimed no alcohol intake before driving, only intake after driving. In all 12 cases, ethanol concentration was lower in the second sample (taken approximately 30 min after the first). The median EtG concentration in the first sample was 4.13 mg/L (range 2.0-7.4) and 4.34 mg/L (range 2.1-7.2) in the second sample. One case showed an increase in EtG concentrations of 15% from first to second sample (the time difference between the samples was 32 min, with the first sample taken 41 min after driving). For the remainder of the cases, EtG concentrations were relatively stable.

CONCLUSIONS

In all the presented cases, the levels of EtG were substantially higher than what would be expected only about 1-2h after a very recent alcohol intake. The relatively stable concentrations between the first and second sample also indicated that the high EtG concentrations were not caused by a rapid formation after a recent intake, as this would have demonstrated increasing concentrations over a time period of 30 min. In conclusion, EtG and EtS in blood could be a helpful tool in assessment of the hip-flask defence, in cases where the detected ethanol is claimed to be caused solely by a single intake after driving.

Biomolecules and Biomarkers Used in Diagnosis of Alcohol Drinking and in Monitoring Therapeutic Interventions

BACKGROUND

The quantitative, measurable detection of drinking is important for the successful treatment of alcohol misuse in transplantation of patients with alcohol disorders, people living with human immunodeficiency virus that need to adhere to medication, and special occupational hazard offenders, many of whom continually deny drinking. Their initial misconduct usually leads to medical problems associated with drinking, impulsive social behavior, and drunk driving. The accurate identification of alcohol consumption via biochemical tests contributes significantly to the monitoring of drinking behavior.

METHODS

A systematic review of the current methods used to measure biomarkers of alcohol consumption was conducted using PubMed and Google Scholar databases (2010-2015). The names of the tests have been identified. The methods and publications that correlate between the social instruments and the biochemical tests were further investigated. There is a clear need for assays standardization to ensure the use of these biochemical tests as routine biomarkers.

FINDINGS

Alcohol ingestion can be measured using a breath test. Because alcohol is rapidly eliminated from the circulation, the time for detection by this analysis is in the range of hours. Alcohol consumption can alternatively be detected by direct measurement of ethanol concentration in blood or urine. Several markers have been proposed to extend the interval and sensitivities of detection, including ethyl glucuronide and ethyl sulfate in urine, phosphatidylethanol in blood, and ethyl glucuronide and fatty acid ethyl esters in hair, among others. Moreover, there is a need to correlate the indirect biomarker carbohydrate deficient transferrin, which reflects longer lasting consumption of higher amounts of alcohol, with serum γ-glutamyl transpeptidase, another long term indirect biomarker that is routinely used and standardized in laboratory medicine.

Ethyl glucuronide and ethyl sulfate

Alcohol misuse is associated with significant morbidity and mortality. Although clinical history, examination, and the use of self-report questionnaires may identify subjects with harmful patterns of alcohol use, denial or under-reporting of alcohol intake is common. Existing biomarkers for detecting alcohol misuse include measurement of blood or urine ethanol for acute alcohol consumption, and carbohydrate-deficient transferrin and gamma-glutamyl transferase for chronic alcohol misuse. There is a need for a biomarker that can detect excessive alcohol consumption in the timeframe between 1 day and several weeks. Ethyl glucuronide (EtG) is a direct metabolite of ethanol detectable in urine for up to 90 h and longer in hair. Because EtG has high specificity for excess alcohol intake, it has great potential for use in detecting "binge" drinking. Using urine or hair, this noninvasive marker has a role in a variety of clinical and forensic settings.

Ethyl glucuronide (EtG): better than breathalyser or self-reports to detect covert short-term relapses into drinking

AIMS

The assessment of relapses is widely used as an outcome measure of alcohol dependence treatment. However, the methods of assessing relapses range from questionnaires to biological markers of alcohol for different time spans. The aim of this study was to compare the relapse rates of weekend home stays during long-term alcohol dependence treatment, assessed by ethyl glucuronide (EtG), breath alcohol tests and self-reports.

METHODS

Two hundred and ninety-seven alcohol-dependent patients receiving a long-term inpatient treatment programme participated. After a weekend at home (Friday to Sunday) they were evaluated for relapse by personal interviews and with breath alcohol tests. A concomitantly collected urine sample was later assessed for EtG with liquid chromatography-tandem mass spectrometry (LC-MS/MS analysis).

RESULTS

Of the total, 37.7% of the patients were positive for EtG at least once. Breath alcohol tests had been positive in only 4.4% and in personal interviews only 5.7% of the patients had admitted relapse. 15.6% of EtG tests were positive, but breath alcohol tests were negative (Cohen's kappa = 0.056). Ninety-three per cent of the relapses were only detected by EtG.

CONCLUSION

In addition to breath alcohol tests and interviews, urinary EtG can clearly improve the verification of relapse in inpatient treatment programmes allowing for weekend stays at home. Without EtG testing, a high amount of relapses will stay undetected.

Assessing the drinking status of liver transplant patients with alcoholic liver disease

The accurate assessment of drinking by patients with alcoholic liver disease is important both before and after liver transplantation. Unfortunately, self-reports by these individuals often underestimate their actual alcohol consumption. Several recently developed biochemical measures can provide additional information on a patient's use of alcohol. This article describes ethyl glucuronide, ethyl sulfate, phosphatidyl ethanol, and carbohydrate-deficient transferrin as biomarkers of drinking and summarizes research dealing with their application in patients with alcohol use disorders who are candidates for or recipients of liver transplantation. The article also offers suggestions for enhancing the reliability of self-report measures of drinking status.

Non-oxidative ethanol metabolites as a measure of alcohol intake

Recent alcohol intake can be monitored by the measurement of indirect biomarkers. Elevated levels of liver enzymes (i.e. gamma-glutamyl transferase (GGT), alanine amino transferase (ALT) and aspartate amino transferase (AST)) in blood are commonly used in clinical practice as an indicator of alcohol-induced liver damage. With the exception of carbohydrate-deficient transferrin (CDT), the specificity of indirect markers is only moderate because many cases of elevated levels are unrelated to alcohol consumption. Because of their intermediate half-life and tendency to accumulate in hair, non-oxidative ethanol metabolites can be used as markers with an intermediate timeframe between ethanol measurements and GGT and CDT with regard to recent alcohol consumption occurring between hours to 1 week. Additionally, these biomarkers offer a high ethanol-specificity in combination with approximately a two-fold higher sensitivity in comparison with indirect alcohol markers. In case of forensic use of direct ethanol metabolites, caution has to be taken in interpretation and pre-analytical pitfalls should be considered.

Higher levels of hair ethyl glucuronide in patients with decreased kidney function

BACKGROUND

Hair levels of ethyl glucuronide (EtG) are often used to differentiate social drinking from heavy drinking. Patients with decreased kidney function have delayed excretion of EtG, and increased incorporation into hair could be suspected. The aim of this study was to compare hair EtG levels in patients with decreased kidney function to those seen in healthy volunteers.

METHODS

Twelve patients with renal disease were included. The levels of EtG in hair were adjusted to estimated daily intake of ethanol (EDI) and compared to 21 previously published healthy individuals.

RESULTS

The levels of hair EtG in the 12 patients ranged between < limit of detection and 134 pg/mg, and the EDI ranged between 0.1 and 12 g. The levels of EtG in hair were significantly higher in the patients compared to healthy volunteers (p = 0.009).

CONCLUSIONS

These preliminary results indicate that hair levels of EtG in a population of patients with decreased kidney function should be interpreted with caution.