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

Biomarkers for monitoring alcohol sobriety after liver transplantation for alcoholic liver disease

Alcoholic liver disease (ALD) has become the most common indication for liver transplantation in Western countries, and its incidence is rapidly increasing in East Asia. Alcohol abstinence remains the standard of care for promoting liver transplantation for ALD and for preventing posttransplant graft loss. However, efficient monitoring methods are still being developed due to the limitations of traditional biomarkers, interviews, and questionnaires. The development of alcohol biomarkers has shifted from detecting alcohol and methanol to indirect byproducts, and to current mid-term and long-term direct alcohol metabolites, which provide higher accuracy and cover almost all types of alcohol relapse detection. However, in most clinical studies, biomarkers are used and validated in healthy individuals and alcohol use disorder (AUD) patients and for pretransplant evaluations. The evidence for their use in posttransplant abstinence monitoring is still lacking, but it is crucial for early detection of alcohol relapse and initiating intervention. This review aims to summarize the current evidence of the use of biomarkers for monitoring sobriety and alcohol relapse after liver transplantation, as well as to cover the diagnostic accuracy, detection window, and optimal multidisciplinary strategies.

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.

Phosphatidylethanol in patients with liver diseases of different etiologies: Analysis of six homologues and comparison with other alcohol markers

BACKGROUND AND AIMS

Phosphatidylethanol (PEth) is a direct alcohol biomarker. Aim of the study was to evaluate the performance of six homologues of PEth in comparison to other alcohol markers in patients with liver diseases.

METHODS

The study included 234 patients with liver disease, who gave statements about alcohol consumption during the three months prior to the doctor's appointment. Ethylglucuronide in urine (uEtG) and in hair (hEtG) and carbohydrate-deficient transferrin (CDT) were analyzed in addition to PEth.

RESULTS

Of all patients 47% stated to have drunk alcohol during the past three months. UEtG, hEtG and CDT showed a sensitivity of 29% and a specificity of 92% together for ingestion of at least two standard drinks (24 g) per week. With PEth 16:0/18:1 in addition, sensitivity increased to 59%. For consumption in the last week uEtG's sensitivity and specificity was 28% and 100%, respectively. PEth's was 75% and 93%. When looking at patients who consumed at least two standard drinks per week during the past three months and of which a hair sample could be obtained, hEtG's sensitivity was 37% and specificity 90%. PEth had a sensitivity of 53% and specificity of 100%. Quotients of PEth 16:0/18:1 with 16:0/18:2, 16:0/20:4 and 18:0/18:2 were smaller when alcohol had been consumed more recently.

CONCLUSION

Despite the rather poor overall sensitivity of alcohol biomarkers in this study, PEth showed best sensitivity for all time periods of alcohol consumption.

Adolescent Gangs: Substance Misuse and Exposure to Adverse Childhood Experiences

Objective: Adult gang members have higher substance misuse and Adverse Childhood Experiences (ACE) prevalence than non-gang involved individuals. The authors aimed to understand UK gang membership demographics and estimate substance misuse and ACE prevalence among a community-based sample of children and young people (CYP) contrasting three groups; gang members, periphery and non-gang involved.Method: The authors used the 2006 Offending, Crime and Justice Survey (OCJS) cross-sectional dataset, containing gang involvement, ACE exposure and substance misuse data, sampling 2,443 individuals aged 13-17 years. Gang membership was self-identified. Gang periphery was CYP identifying as gang involved according to the Eurogang Youth survey questionnaire, but not self-identifying as members. Other CYP were non-gang involved.Results: Gang periphery participants were significantly more likely to misuse all substance types than non-gang involved CYP. The substance misuse likelihood was greatest for gang peripherals, then members, then non-gang involved. Gang periphery and members were significantly more likely to have been a victim of serious assault, less serious assault, any assault, any violence and to have committed any violent act in the last year than non-gang involved.Conclusions: This is the first study comparing ACE exposure and substance misuse prevalence among the UK, community-based CYP sample. Current research highlights younger children with complex needs, including girls, risk gang involvement and requires tailored support to enable safe exit from gangs. Factors relating to gang involvement, ACEs and substance misuse are interlinked and complex, demanding a holistic approach to support across education, children's social services, health and criminal justice settings.

Diagnostic Accuracy of Biomarkers of Alcohol Use in Patients With Liver Disease: A Systematic Review

BACKGROUND AND AIMS

Alcohol-related liver disease is the most frequent cause of cirrhosis and a major indication for liver transplantation. Several alcohol use biomarkers have been developed in recent years and are already in use in several centers. However, in patients with liver disease their diagnostic performance might be influenced by altered biomarker formation by hepatic damage, altered excretion by kidney dysfunction and diuretics use, and altered deposition in hair and nails. We systematically reviewed studies on the diagnostic accuracy of biomarkers of alcohol use in patients with liver disease and performed a detailed study quality assessment.

METHODS

A structured search in PubMed/Medline/Embase databases was performed for relevant studies, published until April 28, 2019. The risk of bias and applicability concerns was assessed according to the adapted quality assessment of diagnostic accuracy studies-2 (QUADAS-2) checklist.

RESULTS

Twelve out of 6,449 studies met inclusion criteria. Urinary ethyl glucuronide and urinary ethyl sulfate showed high sensitivity (70 to 89 and 73 to 82%, respectively) and specificity (93 to 99 and 86 to 89%, respectively) for assessing any amount of alcohol use in the past days. Serum carbohydrate-deficient transferrin showed low sensitivity but higher specificity (40 to 79 and 57 to 99%, respectively) to detect excessive alcohol use in the past weeks. Whole blood phosphatidylethanol showed high sensitivity and specificity (73 to 100 and 90 to 96%, respectively) to detect any amount of alcohol use in the previous weeks. Scalp hair ethyl glucuronide showed high sensitivity (85 to 100%) and specificity (97 to 100%) for detecting chronic excessive alcohol use in the past 3 to 6 months. Main limitations of the current evidence are the lack of an absolute gold standard to assess alcohol use, heterogeneous study populations, and the paucity of studies.

CONCLUSIONS

Urinary and scalp hair ethyl glucuronide are currently the most validated alcohol use biomarkers in patients with liver disease with good diagnostic accuracies. Phosphatidylethanol is a highly promising alcohol use biomarker, but so far less validated in liver patients. Alcohol use biomarkers can complement each other regarding diagnostic time window. More validation studies on alcohol use biomarkers in patients with liver disease are needed.

Impaired diagnostic accuracy of hair ethyl glucuronide testing in patients with renal dysfunction

The impact of renal impairment and hemodialysis on ethyl glucuronide concentrations in hair (hEtG) is not well known. Here, hEtG levels were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in patients presenting to the transplant outpatient clinic and compared with the self-reported alcohol consumption in an anonymous validated questionnaire. Estimated daily alcohol intake (EDI) was calculated. A total of 94 patients with varying renal function (Glomerular filtration rate (GFR) > 60 mL/min: group 1 (n = 47); GFR 30-60 ml/min: group 2 (n = 29); GFR < 30 mL/min: group 3 (n = 18)) were included in the study. Fifteen of 18 (83.3%) patients in group 3 were on dialysis. Altogether, hEtG tested positive (> 5 pg/mg) in 25.5% (n = 24) of patients, while 36.2% (n = 34) and 14.9% (n = 14) of patients reported any or regular (> 10 g/d) alcohol consumption, respectively. The median hEtG concentration of positive samples was much higher in patients in group 3 with advanced renal dysfunction or on dialysis than in patients in group 1 or 2 (group 1, 2, 3 dialysis patients: 74, 52, 145 and 155 pg/mg, respectively), although they consumed on average much less alcohol per day (median EDI group 1, 2, 3, dialysis patients: 16, 17, 3 and 3 g/d, respectively). Also, there was a significant correlation between the hEtG concentration and EDI for patients in group 1 (ρ = 0.84; p = 0.01), but not for patients in group 2 (ρ = -0.35, p = 0.39) or 3 (ρ = 0.02, p = 0.96). Furthermore, the ability of hEtG to correctly identify abstainers as such was lower for patients with advanced renal dysfunction than for the remaining patients (specificity for group 1, 2, 3: 92%, 87%, 82%, respectively). So, monitoring hEtG concentration was less reliable in patients with advanced renal dysfunction or on hemodialysis and by far overestimated the amount of alcohol consumed.

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.

Determination of Ethyl Glucuronide in Hair for Detection of Alcohol Consumption in Patients After Liver Transplantation

BACKGROUND

Early detection of alcohol misuse in orthotopic liver transplantation recipients is essential to offer patients support and prevent organ damage. Here, ethyl glucuronide, a metabolite of ethanol found in hair (hEtG), was evaluated for detection of alcohol consumption.

METHODS

In 104 transplant recipients, 31 with underlying alcoholic liver disease (ALD) and 73 with non-ALD, hEtG was determined in addition to the alcohol markers urine EtG, blood ethanol, methanol, and carbohydrate-deficient transferrin. Results were compared with patients' self-reports in a questionnaire and with physicians' assessments.

RESULTS

By physicians' assessments, 22% of the patients were suspected of consuming alcohol regularly, although only 6% of the patients acknowledged consumption of a moderate or high amount of alcohol. By testing all markers except for hEtG, alcohol consumption was detected in 7% of the patients. When hEtG testing was added to the assessment, consumption was detected in 17% of the patients. Hair-EtG determination alone revealed chronic alcohol consumption of >10 g/d in 15% of the patients. ALD patients had a positive hEtG result significantly more often than non-ALD patients did (32% versus 8%; P = 0.003). Also, the concentration of hEtG was higher in ALD patients (P = 0.049) and revealed alcohol abuse with consumption of >60 g ethanol per day in 23% of ALD and 3% of non-ALD patients. Patients' self-reports and physicians' assessments had a low sensitivity of 27% and 67%, respectively, for detecting regular alcohol intake as indicated by hEtG.

CONCLUSIONS

Hair-EtG determination improved the detection of liver transplant patients who used alcohol, and revealed regular alcohol consumption in 32% of ALD and 8% of non-ALD patients.

Biomarkers for detection of alcohol consumption in liver transplantation

Alcoholic liver disease is an established, yet controversial, indication for liver transplantation. Although an abstinence period of up to 6 mo prior to transplantation is mandatory, alcohol relapse after transplantation is a common event. In case of recurrence of heavy drinking, graft survival is significantly impaired. Guidelines on detection and surveillance of alcohol consumption in this patient cohort are lacking. This review summarizes the challenge of patient selection as well as the current knowledge on established and novel alcohol biomarkers with special focus on liver transplant candidates and recipients.

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.

Trends in drug testing in oral fluid and hair as alternative matrices

The use of alternative matrices such as oral fluid and hair has increased in the past decades because of advances in analytical technology. However, there are still many issues that need to be resolved. Standardized protocols of sample pretreatment are needed to link the detected concentrations to final conclusions. The development of suitable proficiency testing schemes is required. Finally, interpretation issues such as link to effect, adulteration, detection markers and thresholds will hamper the vast use of these matrices. Today, several niche areas apply these matrices with success, such as drugs and driving for oral fluid and drug-facilitated crimes for hair. Once those issues are resolved, the number of applications will markedly grow in the future.

Determination of ethyl glucuronide in hair improves evaluation of long-term alcohol abstention in liver transplant candidates

BACKGROUND & AIMS

Prior to listing patients for Orthotopic liver transplantation (OLT) an abstention period of 6 months is required. Ethyl glucuronide in the hair is a new reliable marker for the assessment of alcohol consumption. Here, the diagnostic value of determining the ethyl glucuronide concentration in the hair of liver transplant candidates was evaluated.

METHODS

In 63 transplant candidates with alcoholic liver cirrhosis and 25 control patients with cirrhosis of other aetiologies alcohol markers, i.e. hEtG, urine EtG, blood ethanol, methanol and carbohydrate deficient transferrin were determined in parallel to an interview with a psychologist.

RESULTS

A total of 19 (30%) transplant candidates admitted alcohol consumption within the last 6 months, while 39/63 (62%) were positive for at least one alcohol marker. In 52% of the 44 candidates denying alcohol consumption, abstention was disproved by detecting at least one positive alcohol marker, in 83% of cases by a positive hEtG result. In the control patients stating abstention from alcohol all hEtG tests were negative. No impact of renal or liver function on hEtG results was detected. A specificity of 98% and a positive predictive value of 92% were calculated for testing hEtG in proximal hair segment and applying a cut-off of 30 pg/mg.

CONCLUSIONS

In 52% of patients denying alcohol consumption within the last 6 months, alcohol abstention was disproved, in 83% of cases by hEtG testing. Therefore, hEtG is a promising new marker for the evaluation of long-term alcohol abstention in liver transplant candidates.

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.

Hair ethyl glucuronide levels as a marker for alcohol use and abuse: a review of the current state of the art

BACKGROUND

Ethyl glucuronide (EtG) is a minor alcohol metabolite that has been proposed as a stable marker in hair to detect and quantify alcohol consumption over long time periods.

METHODS

We provide an outline of currently available techniques for EtG hair sample analysis and highlight the pitfalls related to data interpretation. The literature of EtG analysis has been reviewed from January 1980 up to August 2013. In addition, we present an overview of the clinical and forensic studies which have used EtG quantification in hair as a marker for alcohol consumption/abstinence and we provide suggestions for future research.

RESULTS

EtG is a stable marker in hair that can be used to detect and quantify alcohol consumption over long time periods. This alcohol metabolite remains in hair after complete elimination of alcohol. Currently, there are three main analytical techniques used to quantify EtG in hair: gas chromatography-mass spectrometry (GC-MS), gas chromatography-tandem mass spectrometry (GC-MS/MS), and liquid chromatography-tandem mass spectrometry (LC-MS/MS). No standardized protocols are yet available for the analysis of EtG levels in hair samples, and the current protocols vary in sample preparation and extraction procedures. Variables such as hair length, cosmetic treatment, gender, and pathophysiological conditions influence the final results and should be taken into account.

CONCLUSIONS

EtG quantification in hair is a useful tool for the objective detection of alcohol consumption over extended time periods, but care should be taken when interpreting the results.

[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.

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.