Determination of direct alcohol markers: a review

ZSCAN25 methylation predicts seizures and severe alcohol withdrawal syndrome

Currently, clinicians use their judgement and indices such as the Prediction of Alcohol Withdrawal Syndrome Scale (PAWSS) to determine whether patients are admitted to hospitals for consideration of withdrawal syndrome (AWS). However, only a fraction of those admitted will experience severe AWS. Previously, we and others have shown that epigenetic indices, such as the Alcohol T-Score (ATS), can quantify recent alcohol consumption. However, whether these or other alcohol biomarkers, such as carbohydrate deficient transferrin (CDT), could identify those at risk for severe AWS is unknown. To determine this, we first conducted genome-wide DNA methylation analyses of subjects entering and exiting alcohol treatment to identify loci whose methylation quickly reverted as a function of abstinence. We then tested whether methylation at a rapidly reverting locus, cg07375256, or other existing metrics including PAWSS scores, CDT levels, or ATS, could predict outcome in 125 subjects admitted for consideration of AWS. We found that PAWSS did not significantly predict severe AWS nor seizures. However, methylation at cg07375256 (ZSCAN25) and CDT strongly predicted severe AWS with ATS (p < 0.007) and cg07375256 (p < 6 × 10-5) methylation also predicting AWS associated seizures. We conclude that epigenetic methods can predict those likely to experience severe AWS and that the use of these or similar Precision Epigenetic approaches could better guide AWS management.

Alcohol Consumption Assessed by a Biomarker and Self-Reported Drinking in a Sample of Pregnant Women in the South of Europe: A Comparative Study

(1) Background: Alcohol consumption during pregnancy is a major concern, particularly in Europe and North America. Its prevalence has so far been under-researched. In most studies, the determination of this consumption may be underestimated, as it is based on the information obtained from questionnaires rather than from biomarkers, which will provide a much more reliable approach. The main objective of this study was to compare the prevalence of consumption during pregnancy as assessed by a questionnaire and a hair biomarker. (2) Method: A cross-sectional study with a random sample of 425 pregnant women treated in public hospital consultations in Seville (Spain) and in the 20th week of their pregnancy, orally interviewed using an elaborated ad hoc questionnaire that evaluated variables of sociodemographic, obstetric, and alcohol consumption. Furthermore, the ethyl glucuronide metabolite (EtG) was tested on a hair sample in 252 pregnant women who agreed to facilitate it. Once the data obtained through the questionnaire and hair test were analyzed, the level of metabolites and self-reported alcohol consumption were compared. (3) Results: The prevalence of self-reported alcohol consumption (questionnaire) was 20.7%, and the real consumption (metabolite analysis) was 20.2%. In 16.8% of pregnant women who declared not consuming alcohol during their pregnancy, noticeable consumption was detected according to the metabolite test. No relevant level of variability in estimated alcohol consumption was detected in the biomarker with respect to the sociodemographic and obstetric variables studied. (4) Conclusions: The prevalence of alcohol consumption during pregnancy obtained through both questionnaires and metabolite analyses was similar and high. There is no association between consumption and sociodemographic factors in this sample. The determination of consumption through biomarkers allows for a more accurate approximation of the prevalence of consumption than estimated through questionnaires. Larger sample-sized studies are needed to determine consumption patterns and thus guide the adoption of more precise policies fostering abstinence from alcohol consumption since the preconception period.

An accurate and precise liquid chromatography-tandem mass spectrometry method for the determination of six phosphatidylethanol homologues in whole blood with phospholipid interferences minimized

Alcohol consumption is associated with a wide risk of different diseases, injury and death, and has significant social and economic consequences worldwide. Phosphatidylethanol (PEth) is a group of promising direct alcohol biomarkers, with a significantly longer half-life in blood than ethanol, which can be measured to predict different drinking patterns, such as heavy- and social drinking. This study aimed to develop and validate an accurate and precise LC-MS/MS method for the determination of six PEth homologues in whole blood with minimal interference from unwanted phospholipids. Different organic solvent mixtures for liquid-liquid extraction were investigated to obtain satisfactory recovery of PEth homologues and removal of the lyso-phospholipids and other early eluting phospholipids. The mixture of heptane/2-propanol (80:20, v:v) gave lower phospholipid background and better signal/noise values for the PEth peaks. An LC-MS/MS TQ-S system from Waters was used for the instrumental analysis. The main part of unwanted phospholipids were separated from the PEth homologues on an Acquity BEH C18 column (50 × 2.1 mm ID, 1.7 µm particles) using a buffer-free mobile phase of 0.025 % ammonia in Type 1 water, pH 10.7, as solvent A and methanol as solvent B. Validation and quantification of 22 authentic blood samples showed that the developed LC-MS/MS method is sensitive, precise and accurate for the determination of the six PEth homologues in whole blood. Lower limit of quantification was 10 nM for all compounds. No matrix effects were observed, possibly due to the successful strategies incorporated to avoid the influence of unwanted phospholipids.

Development of an LC-MS/MS assay with automated sample preparation for phosphatidylethanol (PEth)- Not your typical clinical marker

Phosphatidylethanol (PEth) is a group of phospholipids formed exclusively in the presence of ethanol on the erythrocyte membrane, making it a direct biomarker for long-term ethanol consumption for which a clinical reference interval has been established. Here, we describe an assay for quantitation for two most abundant PEth homologues, PEth 16:0/18:1 and PEth 16:0/18:2, from human whole blood, and present challenges overcome throughout the development process. Since PEth is localized within erythrocyte membranes, a reliable sample preparation technique is an important aspect of PEth analysis. Therefore, various erythrocyte lysing agents for recovery of exogenously spiked standards and controls were evaluated to identify one that performed comparably to the recovery of endogenous analytes found in authentic samples. A supported liquid extraction (SLE) technique was employed for sample cleanup and enrichment which together with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis enabled automated sample preparation, appropriate chromatographic resolution, and minimal system carryover. This resulted in a laboratory developed test with an analytical measurement range (AMR) of 10-1000 ng/mL (slope = 0.9902-1.0138, R2 = 0.9958-0.9972), that was precise (intra-day precision: 3.4-4.1%; inter-day precision: 4.4-8.2% over the AMR), accurate when compared with an available external laboratory test (slope = 0.9943-1.0206, R2 = 0.9635-0.9678, no lower decision point interpretation changes), with effective analyte recovery (77.2-83.5%), and established stability characteristics, while chromatographically separating the analytes to ensure no additive effects due to the isotopic distribution of the opposing analyte.

Biomarkers of moderate alcohol intake and alcoholic beverages: a systematic literature review

The predominant source of alcohol in the diet is alcoholic beverages, including beer, wine, spirits and liquors, sweet wine, and ciders. Self-reported alcohol intakes are likely to be influenced by measurement error, thus affecting the accuracy and precision of currently established epidemiological associations between alcohol itself, alcoholic beverage consumption, and health or disease. Therefore, a more objective assessment of alcohol intake would be very valuable, which may be established through biomarkers of food intake (BFIs). Several direct and indirect alcohol intake biomarkers have been proposed in forensic and clinical contexts to assess recent or longer-term intakes. Protocols for performing systematic reviews in this field, as well as for assessing the validity of candidate BFIs, have been developed within the Food Biomarker Alliance (FoodBAll) project. The aim of this systematic review is to list and validate biomarkers of ethanol intake per se excluding markers of abuse, but including biomarkers related to common categories of alcoholic beverages. Validation of the proposed candidate biomarker(s) for alcohol itself and for each alcoholic beverage was done according to the published guideline for biomarker reviews. In conclusion, common biomarkers of alcohol intake, e.g., as ethyl glucuronide, ethyl sulfate, fatty acid ethyl esters, and phosphatidyl ethanol, show considerable inter-individual response, especially at low to moderate intakes, and need further development and improved validation, while BFIs for beer and wine are highly promising and may help in more accurate intake assessments for these specific beverages.

High-resolution imaging in studies of alcohol effect on prenatal development

Fetal alcohol syndrome represents the leading known preventable cause of mental retardation. FAS is on the most severe side of fetal alcohol spectrum disorders that stem from the deleterious effects of prenatal alcohol exposure. Affecting as many as 1 to 5 out of 100 children, FASD most often results in brain abnormalities that extend to structure, function, and cerebral hemodynamics. The present review provides an analysis of high-resolution imaging techniques that are used in animals and human subjects to characterize PAE-driven changes in the developing brain. Variants of magnetic resonance imaging such as magnetic resonance microscopy, magnetic resonance spectroscopy, diffusion tensor imaging, along with positron emission tomography, single-photon emission computed tomography, and photoacoustic imaging, are modalities that are used to study the influence of PAE on brain structure and function. This review briefly describes the aforementioned imaging modalities, the main findings that were obtained using each modality, and touches upon the advantages/disadvantages of each imaging approach.

Epigenetic and Proteomic Biomarkers of Elevated Alcohol Use Predict Epigenetic Aging and Cell-Type variation Better Than Self-Report

Excessive alcohol consumption (EAC) has a generally accepted effect on morbidity and mortality, outcomes thought to be reflected in measures of epigenetic aging (EA). As the association of self-reported EAC with EA has not been consistent with these expectations, underscoring the need for readily employable non-self-report tools for accurately assessing and monitoring the contribution of EAC to accelerated EA, newly developed alcohol consumption DNA methylation indices, such as the Alcohol T Score (ATS) and Methyl DetectR (MDR), may be helpful. To test that hypothesis, we used these new indices along with the carbohydrate deficient transferrin (CDT), concurrent as well as past self-reports of EAC, and well-established measures of cigarette smoking to examine the relationship of EAC to both accelerated EA and immune cell counts in a cohort of 437 young Black American adults. We found that MDR, CDT, and ATS were intercorrelated, even after controlling for gender and cotinine effects. Correlations between EA and self-reported EAC were low or non-significant, replicating prior research, whereas correlations with non-self-report indices were significant and more substantial. Comparing non-self-report indices showed that the ATS predicted more than four times as much variance in EA, CDT4 cells and B-cells as for both the MDR and CDT, and better predicted indices of accelerated EA. We conclude that each of the non-self-report indices have differing predictive capacities with respect to key alcohol-related health outcomes, and that the ATS may be particularly useful for clinicians seeking to understand and prevent accelerated EA. The results also underscore the likelihood of substantial underestimates of problematic use when self-report is used and a reduction in correlations with EA and variance in cell-types.

Prenatal alcohol exposure can be determined from baby teeth: Proof of concept

BACKGROUND

Prenatal alcohol exposure (PAE), leading to fetal alcohol spectrum disorders (FASD), is a serious public health issue in the United States and globally. Diagnosis of FASD is crucial in obtaining appropriate care, but it is not always possible when PAE cannot be documented.

METHODS

Deciduous teeth from a child with known PAE and a child with known absence of PAE were analyzed using liquid chromatography-isotope dilution tandem mass spectrometry (LC-IDMS/MS) in a multiple-reaction monitoring mode for direct markers and LC-high resolution MS in positive and negative mode with hydrophilic interaction liquid chromatography and reverse-phase chromatography, respectively, for indirect markers.

RESULTS

Direct markers of PAE (ethyl glucuronide and ethyl sulfate) were detected in prenatal and postnatal dentine from a case tooth but not from a control tooth. Indirect biomarker analysis indicated a dysregulation of amino acids and an increase in cholesterol sulfate in the case compared to the control tooth.

CONCLUSIONS

This proof-of-concept study demonstrates for the first time that direct biomarkers of PAE are detectable and measurable in deciduous teeth which begin forming in utero and are typically naturally shed between 5 and 12 years of age. Further examination of these novel biomarkers may allow diagnosis of FASD where documentation of PAE is otherwise unavailable. Furthermore, because teeth grow incrementally, defined growth zones can be sampled allowing for identification of gestational timing of PAE to help better understand mechanisms underlying alcohol's disruption of perinatal development.

Development and Validation of a GC-EI-MS/MS Method for Ethyl Glucuronide Quantification in Human Hair

Ethyl glucuronide (EtG) is a minor, non-oxidative ethanol metabolite detectable in several matrices for specific periods of time. In recent years, quantification of EtG in hair has been established as the most reliable biomarker for long-term alcohol consumption, with the Society of Hair Testing offering cut-off values for assessment of both abstinence and heavy drinking. Instrumental constrains and wide inter- and intra-laboratory variability represent the ultimate barriers to widespread acceptance of hair EtG determination in the forensic context. In this study, a new analytical method for hair EtG based on gas chromatographic (GC) separation, electron impact (EI) ionization, and tandem mass spectrometry (MS/MS) detection was developed and validated. At the same time, several parameters for sample pretreatment and instrumental analysis were optimized using real hair samples obtained from different drinking subjects. A full-factorial design-of-experiment approach included procedures for hair washing, pulverization, and extraction. Rigorous multi-step washing proved not to reduce the EtG content extracted in the subsequent sample incubation. Hair pulverization with a ball mill significantly improved the EtG extraction from the keratin matrix and allowed us to reduce the time needed for the subsequent extraction step, without affecting the extraction recovery. The hair extract was derivatized with N-methyl-N-(trimethylsilyl)-trifluoroacetamide. Upon electron impact ionization of the EtG-TMS derivative, triple quadrupole mass analyzers were operated in the selected reaction monitoring (SRM) mode using the fragment m/z 405 as the precursor ion (m/z 410 for the EtG-D5 internal standard), the transitions m/z 405 → 359 and m/z 410 → 359 for quantitation, and m/z 405 → 331 and m/z 405 → 287 for qualification/confirmation, all at 10 V collision energy. The final method was fully validated and then applied to 25 real hair samples. The calibration curve proved linear between 6 and 60 pg/mg. The limit of detection (LOD) was 4 pg/mg. Intra- and inter-assay precision and accuracy tests showed a variability and bias close to 15% or lower over the entire calibration range. The new method is routinely applied in the Italian State Police's toxicology laboratory for hair analyses addressed to exclude excessive alcohol drinking and verify the psycho-physical requirements of the personnel.

Alcohol Use Intensity Decreases in Response to Successful Smoking Cessation Therapy

Smokers frequently drink heavily. However, the effectiveness of smoking cessation therapy for those with comorbid alcohol abuse is unclear, and the content of smoking cessation programs often does not address comorbid alcohol consumption. In order to achieve a better understanding of the relationship between changes in rate of smoking to the change in intensity of alcohol consumption, and the necessity for alcohol-specific programming for dual users, we quantified cigarette and alcohol consumption in 39 subjects undergoing a 3-month contingency management smoking cessation program using recently developed DNA methylation tools. Intake alcohol consumption, as quantified by the Alcohol T Score (ATS), was highly correlated with cg05575921 smoking intensity (adjusted R² = 0.49) with 19 of the 39 subjects having ATS scores indicative of Heavy Alcohol Consumption. After 90 days of smoking cessation therapy, ATS values decreased with the change in ATS score being highly correlated with change in cg05575921 smoking intensity (adjusted R² = 0.60), regardless of whether or not the subject managed to completely quit smoking. We conclude that alcohol consumption significantly decreases in response to successful smoking cessation. Further studies to determine whether targeted therapy focused on comorbid alcohol use increases the success of smoking cessation in those with dual use should be explored.

Cannabis and Alcohol Co-Use and Condomless Anal Sex Among Men Who have Sex with Men Living with HIV: An Event-Level Analysis

Men who have sex with men (MSM) account for more than two thirds of new HIV diagnoses annually. Sexual behavior that increases risk for onward transmission of HIV is associated with both alcohol and cannabis use. However, little is known about the influence of cannabis and alcohol co-use on engagement in condomless anal sex (CAS). The current study explored daily associations between substance use and CAS among HIV-positive MSM using a 42-day timeline followback interview (N = 101). Generalized estimating equation (GEE) logistic regression models were used to examine the association between cannabis and alcohol co-use and CAS at the sexual event while controlling for study site, condition, adherence to antiretroviral therapy, sex-related alcohol expectancies, and partner type. Participants provided data for 1052 sexual activity days, 60.7% of which involved CAS. Of 638 CAS days, 9.1% involved no substances, 72.0% involved either cannabis or alcohol use, and 18.9% involved cannabis and alcohol co-use. Results indicated that the odds of engaging in CAS were higher for sexual events in which cannabis and alcohol co-use occurred (aOR 2.98; 95% CI 1.27, 6.97) compared to events in which no substance use occurred (p = 0.012), but this relationship was no longer significant when cannabis and alcohol co-use was compared to single substance use (aOR 1.57; 95% CI 0.85, 2.90; p = 0.15). Future research should identify specific substance use (e.g., quantity) and partner characteristics (e.g., level of intoxication) that may uniquely influence the relationship between cannabis and alcohol co-use and condomless sex.

The alcohol marker phosphatidylethanol is closely related to AST, GGT, ferritin and HDL-C

BACKGROUND

The aim of this study was to evaluate the quantitative relation between common clinical chemical analyses and ethanol use, measured by a combination of the two alcohol markers phosphatidylethanol (PEth) and carbohydrate-deficient transferrin (CDT).

METHODS

Results of PEth and CDT in whole blood and serum, respectively, were included, together with information on 10 different commonly measured clinical chemical analytes, as well as age and sex. PEth was analysed by UPC² -MS/MS and CDT was measured by capillary electrophoresis.

RESULTS

Samples from 4873 patients were included. The strongest relation to alcohol consumption as measured by PEth, when correcting for age and sex, was found for HDL-C (standardized β = 0.472, p < 0.001), AST (standardized β = 0.372, p < 0.001), ferritin (standardized β = 0.332, p < 0.001) and GGT (standardized β = 0.325, p < 0.001). The relation to PEth was weak for total cholesterol, TG and ALP. No relation was found for Hb and LDL-C.

CONCLUSIONS

When using PEth as a marker for alcohol consumption, this study demonstrated the quantitative relation to commonly used test as AST or GGT, but also an important relation to ferritin or HDL-C. In clinical practice, elevated levels of these clinical chemical analytes should initiate further work-up on possibly harmful alcohol use.

[Diagnosis and Severity Assessment of Alcohol-Related Liver Disease]

A diagnosis of alcohol-related liver disease (ALD) requires information on the history of excessive alcohol consumption (average intake of 40 g or more in men and 20 g or more in women a day). Furthermore, blood tests, such as GGT, AST, ALT, and mean corpuscular volume, and imaging studies, including abdominal ultrasound or transient elastography, are also useful. A liver biopsy can be useful for confirming the diagnosis and has prognostic value. ALD includes alcoholic fatty liver, alcoholic hepatitis, and alcoholic cirrhosis, and in most cases, clinical manifestations can overlap. The prognostic scoring systems of ALD are limited mainly to alcoholic hepatitis, and the early mortality and treatment response can be predicted using various scoring systems. This review summarizes how to diagnose and evaluate the severity of ALD in clinical practice.

Quantitative Determination of Ethyl Glucuronide and Ethyl Sulfate in Postmortem and Antemortem Whole Blood Using Phospholipid Removal 96-Well Plate and UHPLC-MS-MS

Postmortem ethanol formation is a well-known problem in forensic toxicology. Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are ethanol metabolites that can be used to distinguish antemortem alcohol intake from postmortem formation of ethanol and in addition can be a helpful tool in assessment of the hip-flask defense. To an aliquot of 100 µL whole blood, internal standard (IS) and water was added before protein precipitation treatment (PPT) with ice-cold acetonitrile (ACN). The supernatants were filtered through a 96-well phospholipid removal plate, evaporated to dryness and reconstituted in 150 µL water/ACN/formic acid (FA). Identification of compounds was performed using multiple reaction monitoring (MRM) in negative mode. Gradient elution was performed on a C18 column with methanol (MeOH) and 0.1% FA. The run time was 4.5 min, and 0.5 µL was injected on an ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS-MS) instrument. Linearity was achieved (coefficient of determination (R²) ≥ 0.999) for EtG in the range of 0.089 to 22 mg/L (0.40–100 µM) and EtS 0.025 to 6.3 mg/L (0.20–50 µM). The limit of quantification (LOQ) was 0.067 mg/L (0.30 µM) for EtG and 0.019 mg/L (0.15 µM) for EtS. Between assay accuracy was –15% to 8% and precision reported as relative standard deviation (RSD) was ≤ 4.5%. Precision, estimated as the RSD of the concentration difference between results from two independent analyses of authentic whole blood samples, was ≤ 6.7%. Recovery was ≥ 61% for EtG and ≥ 77% for EtS and matrix effects (ME) were 99% to 103%. Method comparison was carried out with a previously used UHPLC–MS-MS method, and satisfactory agreement was achieved, and external proficiency testing control samples had z-score < ± 1. The method has been used in routine work for more than 4 years analyzing about 6,000 antemortem and postmortem whole blood samples and has proven to be robust and reliable.

Alcohol and melatonin

Investigation of the pathogenesis of alcoholism in humans using different methodological approaches has facilitated detection of important biological factors of consequent metabolic diseases, endocrine disorders, and other medical conditions, such as alcoholic cardiomyopathy, alcoholic hypertension, heart and vascular lesions, alcoholic liver disease, alcoholic pancreatitis, etc. Alcohol abuse leads to damage to the nervous system, which can result in neurological and mental disorders, including alcoholic polyneuropathy, psychosis, and alcohol dementia. The complexity and versatility of the harmful effects of regular alcohol consumption on the human body can be considered in the perspective of a chronobiological approach, because alcohol is chronotoxic to biological processes. As a rhythm regulator, melatonin exerts a wide range of different effects: circadian rhythm regulation, thermoregulation, sleep induction, antioxidant, immunomodulatory, and anti-stress ones. This review presents from a chronobiological perspective the impact of melatonin on alcohol intoxication in terms of mental disorders, sleep and inflammation, hepatic injury, and mitochondrial function. It discusses the main clinical effects of melatonin on alcohol injury and the main targets as a therapy for alcohol disorders. Chronobiological effects of ethanol are related to melatonin suppression that has been associated with, among others, cancer risk. Exogenous melatonin seems to be a promising hepato- and immune-protector due to its antioxidant and anti-inflammatory properties, which in combination with other medicines makes it useful to prevent alcoholic organ damage. The reason for the scientific interest in melatonin as a treatment for alcoholism is obvious; the number of cases of this pathology that gives rise to metabolic syndrome, and its subsequent transformation into steatohepatitis, liver fibrosis, and cirrhosis, is increasing worldwide. Melatonin not only exerts antioxidant effects but it exerts various other effects contributing to the management of liver conditions. This review discusses the interaction between normal and pathological processes caused by alcohol consumption and the relationship between alcohol and melatonin in these conditions.

Development and validation of a method for the simultaneous analysis of fatty acid ethyl esters, ethyl sulfate and ethyl glucuronide in neonatal meconium: application in two cases of alcohol consumption during pregnancy

Alcohol consumption during pregnancy constitutes one of the leading preventable causes of birth defects and neurodevelopmental disorders in the exposed children. Fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG) and ethyl sulfate (EtS) have been studied as potential biomarkers of alcohol consumption. However, most analytical approaches proposed for their analysis in meconium samples consist of separated extraction procedures requiring the use of two meconium aliquots, which is costly in terms of both time and materials. Therefore, the aim of this study was to develop and validate a method for the simultaneous extraction of 9 FAEEs, EtG and EtS from one meconium aliquot. The sample was homogenized using methanol, and then FAEEs were extracted with hexane while EtG and EtS were isolated using acetonitrile. Then, extracts were applied to solid-phase extraction columns and analysed by gas chromatography mass spectrometry (FAEEs) and liquid chromatography tandem mass spectrometry (EtG and EtS). Calibration curves were linear with r values greater than 0.99. The LODs ranged from 0.8 to 7.5 ng/g for FAEEs and were 0.2 ng/g and 0.8 ng/g for EtS and EtG, respectively. LOQs ranged from 5 to 25 ng/g for FAEEs and were 1 ng/g and 2.5 ng/g for EtS and EtG, respectively. Accuracies and precisions were between 93.8 and 107% and between 3.5 and 9.7%, respectively. The recovery values ranged from 89.1 to 109%. The method proved to be sensitive, specific, simple and fast and allowed for the reduction of the amount of organic solvent used for extraction compared to other published data while higher recoveries were obtained. The method was used for analysis of meconium samples in two cases of mothers who were consuming alcohol during pregnancy.

Clinical usefulness of a urine dipstick to detect ethyl glucuronide (EtG): A quantitative clinical study in healthy young female volunteers

The metabolite of ethanol, ethyl glucuronide (EtG), reflects alcohol intake longer than ethanol and is used as a biomarker in clinical settings to detect alcohol use. We aimed to assess the clinical usefulness in a low-to-moderate alcohol intake setting and validate a new urine EtG dipstick. A three-way, open, cross-over trial was conducted. Data were collected from January to June 2019. Among 12 healthy female volunteers, we quantified urine EtG and used a dipstick following intake of either one, two or four units of alcohol. Main outcomes were concentrations of EtG in urine and serum, and creatinine and ethanol in serum. EtG in urine was determined dichotomously by dipsticks at two different thresholds and by mass spectrometry used as gold standard. EtG in urine was quantifiable up to 24 hours after alcohol intake. In some individual cases, EtG was quantifiable up to 72 hours at low concentrations. The dipstick detected EtG in urine up to 24 hours. At thresholds of 1000 and 1500 ng/mL, the dipsticks had a specificity of 100% (both), while sensitivity was 84% and 69%, respectively. The sensitivity of the dipsticks was insufficient to support a screening purpose in this setting of low-to-moderate alcohol intake.

Performance of self-reported measures of alcohol use and of harmful drinking patterns against ethyl glucuronide hair testing among young Swiss men

Background

There is a need for empirical studies assessing the psychometric properties of self-reported alcohol use as measures of excessive chronic drinking (ECD) compared to those of objective measures, such as ethyl glucuronide (EtG).

Objectives

To test the quality of self-reported measures of alcohol use and of risky single-occasion drinking (RSOD) to detect ECD assessed by EtG.

Methods

A total of 227 samples of hair from young Swiss men were used for the determination of EtG. Self-reported measures of alcohol use (previous twelve-month and previous-week alcohol use) and RSOD were assessed. Using EtG (<30 pg/mg) as the gold standard of ECD assessment, the sensitivity and specificity were computed, and the AUROC were compared for alcohol use measures and RSOD. Logistic regressions were used to test the contribution of RSOD to the understanding of ECD after controlling for alcohol use.

Results

A total of 23.3% of participants presented with ECD. Previous twelve-month alcohol use with a cut-off of >15 drinks per week (sensitivity = 75.5%, specificity = 78.7%) and weekly RSOD (sensitivity = 75.5%, specificity = 70.1%) yielded acceptable psychometric properties. No cut-off for previous-week alcohol use gave acceptable results. In the multivariate logistic regression, after controlling for the previous twelve months of alcohol use, RSOD was still significantly associated with EtG (p = .016).

Conclusion

Self-reported measures of the previous twelve months of alcohol use and RSOD were acceptable measures of ECD for population-based screening. Self-reported RSOD appeared to be an interesting screening measure, in addition to the previous twelve months of alcohol use, to understand ECD among young people.

The Relationship Between Ingested Dose of Ethanol and Amount of Ethyl Glucuronide Formed in Blood

A positive non-linear relation between the dose of ethanol ingested and the area under the curve (AUC) for ethyl glucuronide (EtG) in urine is previously observed. The relation between both doses and AUC of ethanol and the AUC for EtG in blood is not previously published, and this study aimed to investigate this relationship. After an overnight fast, 10 healthy volunteers ingested 0.5-g ethanol per kilo body weight (low dose) in one occasion and 1.0-g ethanol per kilo body weight (high dose) in the next occasion. Results showed that there was a significant higher median ratio between blood AUC for EtG and dose of ethanol in the high-dose (8.99; range 7.37–10.94) group compared to the low-dose (5.02; range 4.25–6.15) group (P = 0.005). The median ratio between the AUC for EtG and AUC for ethanol was actually significantly higher in the low-dose (1.77; range 1.51–2.24) group compared to the high-dose (1.67; range 1.30–2.02) group (P = 0.005), although values are quite similar. This study therefore showed that the ratio between the AUC for EtG in blood and dose of ethanol is higher after intake of 1.0 g/kg than 0.5 g/kg. This pattern is however not seen when AUC for EtG is compared to AUC for ethanol. Results therefore support that the percentage of ethanol converted to EtG is not increasing when the doses increase. An explanation for the positive non-linear relation previously observed between the dose of ethanol ingested and amount of EtG formed may be a relative higher first-pass metabolism of ethanol at lower doses.

Blood phosphatidyl ethanol levels as a tool to detect alcohol misuse in trauma patients

INTRODUCTION

There is a strong need for a reliable marker of harmful alcohol consumption to identify injured patients that can benefit from alcohol interventions, and blood phosphatidyl ethanol (PEth) has not previously been tested on this population. This study aims to compare the performance of blood PEth concentration, blood alcohol concentration (BAC) and the Alcohol Use Disorders Identification Test Consumption (AUDIT-C) for the screening of alcohol misuse in trauma patients.

METHODS

Prospective cross-sectional study of 238 adult patients presenting in the emergency department with any type of trauma. PEth concentration was determined in whole blood by high-performance liquid chromatography with tandem mass spectrometry. Consent, AUDIT-C score and demographic data were obtained.

RESULTS

The sample consisted of majority male (67.6%), single (46.2%) and employed (66%) patients. The most common type of trauma was traffic collision (63.9%). The mean age was 41.7 years. We found a significant correlation between PEth levels with AUDIT-C score (Spearman's r = 0.654; p < .0001). PEth had an area under the ROC curve of 0.885 to detect hazardous alcohol consumption (AUDIT-C score ≥ 6) and PEth ≥23.9 ng/mL cutoff point provided 91.2% of sensitivity and 78.4% of specificity. Twelve patients reported alcohol abstinence, but had quantifiable levels of PEth.

CONCLUSIONS

PEth levels and AUDIT-C score had a moderate correlation in our population. PEth was useful to identify 12 cases of underreporting of alcohol consumption habits. PEth shows promising results, but more research is needed to identify the best screening tool for alcohol misuse in trauma patients.

Fetus morphology changes by second-trimester ultrasound in pregnant women drinking alcohol

Fetal alcohol spectrum disorders (FASDs) are a group of negative conditions occurring in children exposed to alcohol during gestation. The early discovery of FASD is crucial for mother and infant follow-ups. In this study, we investigated in pregnant women the association between urine ethylglucuronide (EtG-a biomarker of alcohol drinking) and indicators of the physical characteristics of FASD by prenatal ultrasound in the second trimester of gestation. We also correlated these data with the AUDIT-C, T-ACE/TACER-3, TWEAK, and food habit diary, screening questionnaires used to disclose alcohol drinking during pregnancy. Forty-four pregnant women were randomly enrolled and examined for ultrasound investigation during the second trimester of gestation. Urine samples were provided by pregnant women immediately after the routine interviews. EtG determinations were performed with a cutoff established at 100 ng/mL, a value indicating occasional alcohol drinking. Fifteen of the enrolled pregnant women overcame the EtG cutoff (34.09%). Analysis of variance (ANOVA) revealed that the fetuses of the positive EtG pregnant women had significantly longer interorbital distance and also significantly increased frontothalamic distance (P's < 0.02). Quite interestingly, no direct correlation was found between EtG data and both food diary and AUDIT-C. However, a significant correlation was observed between urinary EtG and T-ACE (r = 0.375; P = 0.012) and between urinary EtG and TWEAK (r = 0.512; P < 0.001) and a concordance with all questionnaire for EtG values higher than 500 ng/mL. This study provides clinical evidence that the diagnosis of maternal alcohol consumption during pregnancy by urine EtG may disclose FASD-related damage in the fetus.

Non-oxidative ethanol metabolism in human hepatic cells in vitro: Involvement of uridine diphospho-glucuronosyltransferase 1A9 in ethylglucuronide production

Ethanol is the most frequently psychoactive substance used in the world, leading to major public health problems with several millions of deaths attributed to alcohol consumption each year. Metabolism of ethanol occurs mainly in the liver via the predominant oxidative metabolism pathway involving phase I enzymes including alcohol dehydrogenases (ADH), cytochrome P450 (CYP) 2E1 and catalase. In a lesser extent, an alternative non-oxidative pathway also contributes to the metabolism of ethanol, which involves the uridine diphospho-glucuronosyltransferase (UGT) and sulfotransferase (SULT) phase II enzymes. Using liquid chromatography-high resolution mass spectrometry, ethylglucuronide (EtG) and ethylsulfate (EtS) produced respectively by UGT and SULT conjugation and detected in various biological samples are direct markers of alcohol consumption. We report herein the efficient non-oxidative metabolic pathway of ethanol in human differentiated HepaRG cells compared to primary human hepatocytes (HH). We showed dose- and time-dependent production of EtS and EtG after ethanol (25 or 50 mM) treatment in culture media of differentiated HepaRG cells and HH and a significant induction of CYP2E1 mRNA expression upon acute ethanol exposure in HepaRG cells. These differentiated hepatoma cells thus represent a suitable in vitro human liver cell model to explore ethanol metabolism and more particularly EtG and EtS production. In addition, using recombinant HepG2 cells expressing different UGT1A genes, we found that UGT1A9 was the major UGT involved in ethanol glucuronidation.

Identifying an accurate self-reported screening tool for alcohol use disorder: evidence from a Swiss, male population-based assessment

BACKGROUND AND AIMS

Short screenings for alcohol use disorder (AUD) are crucial for public health purposes, but current self-reported measures have several pitfalls and may be unreliable. The main aim of our study was to provide empirical evidence on the psychometric performance of self-reports currently used. Our research questions were: compared with a gold standard clinical interview, how accurate are (1) self-reported AUD, (2) self-reported alcohol use over time and (3) biomarkers of alcohol use among Swiss men? Finally, we aimed to identify an alternative screening tool.

DESIGN

A single-center study with a cross-sectional design and a stratified sample selection.

SETTING

Lausanne University Hospital (Switzerland) from October 2017 to June 2018.

PARTICIPANTS

We selected participants from the French-speaking participants of the ongoing Cohort Study on Substance Use and Risk Factors (n = 233). The sample included young men aged on average 27.0 years.

MEASUREMENTS

We used the Diagnostic Interview for Genetic Studies as the gold standard for DSM-5 AUD. The self-reported measures included 11 criteria for AUD, nine alcohol-related consequences, and previous 12 months' alcohol use. We also assessed biomarkers of chronic excessive drinking (ethyl glucuronide and phosphatidylethanol).

FINDINGS

None of the self-reported measures/biomarkers taken alone displayed both sensitivity and specificity close to 100% with respect to the gold standard (e.g. self-reported AUD: sensitivity = 92.3%, specificity = 45.8%). The best model combined eight self-reported criteria of AUD and four alcohol-related consequences. Using a cut-off of three, this screening tool yielded acceptable sensitivity (83.3%) and specificity (78.7%).

CONCLUSIONS

Neither self-reported alcohol use disorder nor heavy alcohol use appear to be adequate to screen for alcohol use disorder among young men from the Swiss population. The best screening alternative for alcohol use disorder among young Swiss men appears to be a combination of eight symptoms of alcohol use disorder and four alcohol-related consequences.

An LC-MS/MS method for comparing the stability of ethanol's non-oxidative metabolites in dried blood spots during 90 days

Problems of stability were found for biomarkers of alcohol consumption: ethyl glucuronide (EtG), ethyl sulfate (EtS), phosphatidylethanols (PEths), and fatty acid ethyl esters (FAEEs) in whole blood. The purpose of this study was to establish a method for the determination of these four kinds of ethanol's non-oxidative metabolites in dried blood spots (DBS) by liquid chromatography tandem mass spectrometry (LC-MS/MS), and to evaluate their stability. In this method, 50 μL of human blood was spotted onto a filter paper for DBS analysis. Samples were extracted by methanol, reconstituted by 2-propanol, and injected into the LC-MS/MS system. Limits of detection were among 0.5-50 ng/mL, and deviations in accuracy and precision were all lower than 15% at three quality control levels. The stability of the four kinds of ethanol non-oxidative metabolites in DBS was investigated during a 90-day range under three temperatures, -20 °C, 4 °C, and 25 °C. EtG and EtS showed a high level of stability in DBS in the 90-day range, regardless of the temperature. FAEEs were unstable after three days. PEths showed stability within 15 days in postmortem DBS and 60 days in antemortem DBS, respectively, at all temperatures.

Association of Fatty Acid Ethyl Esters in Meconium of Neonates with Growth Deficits at Birth: a Prospective, Single-Centre Cohort Study

BACKGROUND

In this prospective cohort study, we investigated the association between fatty acid ethyl esters (FAEEs) in meconium as biomarkers of prenatal ethanol exposure and growth deficits, as birth outcomes, that constitute several of the key cardinal features of fetal alcohol syndrome.

METHODS

A total of 157 meconium samples were collected from enrolled infants within 24 hours of birth, and nine FAEEs were quantified using liquid chromatography/tandem mass spectrometry. The relationships between cumulative concentrations of nine species of FAEEs in meconium and birth parameters of growth (age-sex-specific centiles of head circumference [HC], weight, and length) and respective and combined birth outcomes of growth deficits (HC ≤ 10th centile, weight ≤ 10th centile, and length ≤ 10th centile) were determined.

RESULTS

Multivariate logistic regression analysis demonstrated that higher cumulative concentrations of meconium FAEEs correlated with elevated risks for HC and length, both, 10th percentile or less (adjusted odds ratio [aOR], 2.94; 95% confidence interval [CI], 1.12-7.74; P = 0.029) and HC and weight and length, all of them, 10th percentile or less (aOR, 3.27; 95% CI, 1.12-9.59; P = 0.031).

CONCLUSION

The elevated cumulative FAEEs in meconium were associated with combined growth deficits at birth, specifically HC and length, both, 10th percentile or less, which might be correlated with detrimental alcohol effects on fetal brain and bone development, suggesting a plausible alcohol-specific pattern of intrauterine growth restriction.

Genome-wide and digital polymerase chain reaction epigenetic assessments of alcohol consumption

The lack of readily employable biomarkers of alcohol consumption is a problem for clinicians and researchers. In 2014, we published a preliminary DNA methylation signature of heavy alcohol consumption that remits as a function of abstinence. Herein, we present new genome-wide methylation findings from a cohort of additional subjects and a meta-analysis of the data. Using DNA from 47 consecutive heavy drinkers admitted for alcohol detoxification in the context of alcohol treatment and 47 abstinent controls, we replicate the 2014 results and show that 21,221 CpG residues are differentially methylated in active heavy drinkers. Meta-analysis of all data from the 448,058 probes common to the two methylation platforms shows a similarly profound signature with confirmation of findings from other groups. Principal components analyses show that genome-wide methylation changes in response to alcohol consumption load on two major factors with one component accounting at least 50% of the total variance in both smokers and nonsmoking alcoholics. Using data from the arrays, we derive a panel of five methylation probes that classifies use status with a receiver operator characteristic area under the curve (AUC) of 0.97. Finally, using droplet digital polymerase chain reaction (PCR), we convert these array-based findings to two marker assays with an AUC of 0.95 and a four marker set AUC of 0.98. We conclude that DNA methylation assessments are capable of quantifying alcohol use status and suggest that readily employable digital PCR approaches for substance consumption may find widespread use in alcohol-related research and patient care.

Non-Linear Formation of EtG and FAEEs after Controlled Administration of Low to Moderate Doses of Ethanol

Aims

Ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEEs) are non-oxidative metabolites of alcohol that can be detected in conventional and non-conventional biological matrices for longer periods than alcohol. The aim was to describe the time courses of both biomarkers after ingestion of acute low-moderate doses of ethanol.

Methods

The study design was double-blind, randomized, crossover and controlled with placebo. Participants were distributed in three different cohorts: (a) Cohort-1: two doses of 18 and 30 g of ethanol and placebo were administered to 12 subjects; (b) Cohort-2: two doses of 6 and 12 g of ethanol and placebo were administered to six subjects and (c) Cohort-3: two doses of 24 and 42 g of ethanol and placebo were administered to six subjects. Each participant received two doses of ethanol and placebo. Plasma concentrations (0-6 h) of ethanol and specific FAEEs (palmitic, stearic, linoleic and oleic acid ethyl esters) and urinary concentrations of EtG (0-24 h) were measured.

Results

A dose-dependent increase in blood ethanol concentrations was observed. EtG excretion and FAEEs plasmatic concentrations showed a disproportionate increase with the ethanol dose suggesting non-linearity. Area under the curve (AUC0-6h) of ethanol concentrations showed a linear trend with non-oxidative metabolites' concentrations.

Conclusion

The formation rate of ethanol non-oxidative biomarkers does not follow a linear trend, explained mainly by a disproportionate increase in AUC0-6h of ethanol concentrations in relation to dose. This observation should be taken into account when interpreting results in biological matrices in clinical and forensic settings.

Short summary

A double-blind, randomized, crossover and controlled study was conducted administering ethanol (6-42 g). Ethyl glucuronide (EtG) excretion and fatty acid ethyl esters (FAEEs) plasmatic concentrations showed a disproportionate increase with the ethanol dose suggesting non-linearity. This observation should be taken into account when interpreting biomarker concentrations in clinical settings.

Drug exposure during pregnancy: analytical methods and toxicological findings

Drug use during pregnancy constitutes a major preventable worldwide public health issue. Birth defects, growth retardation and neurodevelopmental disorders are associated with tobacco, alcohol or drugs of abuse exposure during pregnancy. Besides these adverse health effects, drug use during pregnancy also raises legal and social concerns. Identification and quantification of drug markers in maternal and newborn biological samples offers objective evidence of exposure and complements maternal questionnaires. We reviewed the most recent analytical methods for quantifying drugs of abuse, tobacco, alcohol and psychotropic drugs in maternal, newborn and maternal-fetal unit biological samples by gas and liquid chromatography coupled to mass spectrometry. In addition, manuscripts comparing the usefulness of different biological samples to detect drug exposure during pregnancy were reviewed.

Monitoring people at risk of drinking by a rapid urinary ethyl glucuronide test

Alcohol and illicit drug abuse are major public health problems worldwide. Since alcohol is the predominant substance of choice in polydrug abusers, monitoring its use, along with urinary drug screening in patients in rehabilitation programs, appeared to be crucial in identifying patients at risk of alcohol disorders leading to impaired quality of life. Ethyl β-D-6-glucuronide, a non-oxidative, non-volatile, stable and minor direct ethanol metabolite, has a 6h to 4 day window of detection in urine after the last alcohol intake. Each of the 119 subjects (85 males, 34 females) registered with the Public Health Service for Drug Dependence Treatment provided a urine sample for ethylglucoronide (EtG) determination in an immunochemical test with a 500 ng/ml cutoff. All results were evaluated with confirmation criteria of a fully validated gas chromatography/mass spectrometry assay. The diagnostic performance of the EtG immunochemical test was assessed using Receiver Operating Characteristic Curve analysis. The immunochemical test specificity was 100% for EtG urinary values above 500 ng/ml. No false positive results were found. With levels below 500 ng/ml, 12% of the samples were classified as negative. The average consumption of the incorrectly classified subjects was 171 ng/ml, with a misclassification error of 6.5% to 18.5%. High agreement between EtG as determined in an immunochemical test and gas chromatography/mass spectrometry, suggests that the rapid EtG test is a reliable, cost-effective alcohol monitoring assay for patient management in many non-forensic settings, such as drug rehabilitation programs.

DNA methylation as a predictor of fetal alcohol spectrum disorder

Background

Fetal alcohol spectrum disorder (FASD) is a developmental disorder that manifests through a range of cognitive, adaptive, physiological, and neurobiological deficits resulting from prenatal alcohol exposure. Although the North American prevalence is currently estimated at 2-5%, FASD has proven difficult to identify in the absence of the overt physical features characteristic of fetal alcohol syndrome. As interventions may have the greatest impact at an early age, accurate biomarkers are needed to identify children at risk for FASD. Building on our previous work identifying distinct DNA methylation patterns in children and adolescents with FASD, we have attempted to validate these associations in a different clinical cohort and to use our DNA methylation signature to develop a possible epigenetic predictor of FASD.

Methods

Genome-wide DNA methylation patterns were analyzed using the Illumina HumanMethylation450 array in the buccal epithelial cells of a cohort of 48 individuals aged 3.5-18 (24 FASD cases, 24 controls). The DNA methylation predictor of FASD was built using a stochastic gradient boosting model on our previously published dataset FASD cases and controls (GSE80261). The predictor was tested on the current dataset and an independent dataset of 48 autism spectrum disorder cases and 48 controls (GSE50759).

Results

We validated findings from our previous study that identified a DNA methylation signature of FASD, replicating the altered DNA methylation levels of 161/648 CpGs in this independent cohort, which may represent a robust signature of FASD in the epigenome. We also generated a predictive model of FASD using machine learning in a subset of our previously published cohort of 179 samples (83 FASD cases, 96 controls), which was tested in this novel cohort of 48 samples and resulted in a moderately accurate predictor of FASD status. Upon testing the algorithm in an independent cohort of individuals with autism spectrum disorder, we did not detect any bias towards autism, sex, age, or ethnicity.

Conclusion

These findings further support the association of FASD with distinct DNA methylation patterns, while providing a possible entry point towards the development of epigenetic biomarkers of FASD.

[The comparative analysis of the methods for the determination of phosphatidylethanol in blood as a biological marker of alcohol abuse]

The confirmation of the fact of alcohol abuse is currently an important problem of both medical and social significance. Of all biological markers of alcohol consumption presently in use, blood phosphatidylethanol (PEth) is considered to be most sensitive and specific one. Therefore it has promising prospects for the further application. There is no universally accepted method for the calculation of the phosphatidylethanol concentration in human blood. For this reason, the present article places emphasis on the comparative characteristic of various methods for the determination of this substance.

Metabolomics and fetal alcohol spectrum disorder

Fetal alcohol spectrum disorder (FASD) is a major public health issue that encompass an array of physical, neurological, and behavioral effects due to alcohol consumption during pregnancy. The classical biomarkers of FASD that are currently used lack sensitivity and specificity, and as such there is an opportunity through the use of novel metabolomics analysis to identify new biomarkers to identify those at risk for FASD, which could more effectively aid in early intervention. The focus of this minireview is to identify current work that is being done in the field of metabolomics in FASD in utero, and to highlight promising metabolites that could act as biomarkers in the future. We will conclude with suggestions for further research, as there is a large gap of knowledge in this particular area of metabolomics.

Phosphatidylethanol (PEth) as a Biomarker of Alcohol Consumption in HIV-Infected Young Russian Women: Comparison to Self-Report Assessments of Alcohol Use

Alcohol use is particularly deleterious for HIV-infected individuals and thus accurate assessment of alcohol consumption is crucial in this population. Phosphatidylethanol (PEth) provides an objective assessment of drinking and can be compared to self-reported alcohol assessments to detect underreporting. The purpose of this study was to identify underreporting and its potential predictors in an HIV-infected sample of young Russian women. The current study examined the concordance between a quantitative measure of PEth and self-reported recent alcohol consumption in a prospective sample of HIV-infected young women (N = 204) receiving medical care in Saint Petersburg, Russia. At baseline, 53% of participants who denied drinking in the prior 30 days tested positive for PEth (i.e., underreporters), although this rate decreased significantly at a three-month follow-up assessment. Further exploration did not identify consistent predictors of underreporting status. Quantitative PEth levels showed, at best, modest overlap to self-reported alcohol consumption among those reporting alcohol use (e.g., Spearman's r = 0.27 between PEth and total drinks past-30 days at baseline). Objective measures of alcohol consumption demonstrate modest overlap with self-report measures of use in HIV-infected young Russian women. Incorporating objective and quantifiable biological markers are essential for valid assessments of alcohol use.

Is it possible to detect PEth 16:0/18:1 and PEth 18:1/18:1 in red blood cells after 20 years of storage in liquid nitrogen?

INTRODUCTION

Phosphatidylethanol (PEth), as measured in freshly drawn blood samples, could be a promising new biomarker for habitual alcohol consumption, but it is still unknown whether PEth can also be determined from blood samples having been stored frozen for a longer period.

MATERIALS AND METHODS

PEth 16:0/18:1 and PEth 18:1/18:1 were determined by LC-MS/MS from red blood cells (RBC) derived from blood samples of (I) 20 healthy volunteers (after 1 month of storage at -80 °C) and (II) 232 participants of the population-based European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg study (after 20 years of storage at -196 °C). Analyses involved liquid-liquid extraction from 100 μl aliquots with phosphatidylpropanol (PProp 18:1/18:1) as the internal standard. Extracts were subjected to a 10-min LC gradient separation, using multiple reaction monitoring of deprotonated molecules for quantification.

RESULTS

After 1 month of storage at -80 °C, PEth was detectable in all samples at mean concentrations of 393.6 ± 12.4 ng/ml (PEth 16:0/18:1) and 43.3 ± 1.1 ng/ml (PEth 18:1/18:1). In samples stored for 20 years at -196 °C, PEth was detectable in 23.7% of all samples at mean concentrations of 412.2 ± 655.5 ng/ml (PEth 16:0/18:1) and 38.0 ± 74.8 ng/ml (PEth 18:1/18:1).

DISCUSSION AND CONCLUSION

PEth can be determined reliably from samples of moderate habitual alcohol consumers after 1 month of storage at -80 °C. Our data suggest that PEth is generally also detectable in samples after 20 years of storage at -196 °C. Further studies are needed to assess the still unknown impact of storage duration and temperature on different PEth specimen concentrations.

Simultaneous determination of ethanol's four types of non-oxidative metabolites in human whole blood by liquid chromatography tandem mass spectrometry

The importance of ethanol non-oxidative metabolites as the specific biomarkers of alcohol consumption in clinical and forensic settings is increasingly acknowledged. Simultaneous determination of these metabolites can provide a wealth of information like drinking habit and history, but it was difficult to achieve because of their wide range of polarity. This work describes development and validation of a simple liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for 4 types of ethanol non-oxidative metabolites (ethyl glucuronide, ethyl sulfate, fatty acid ethyl esters and phosphatidylethanols) in 50 μL of human whole blood. Pretreatment method, column and MS conditions were optimized. For the first time, the four types of ethanol non-oxidative metabolites with enormous discrepancies of property were simultaneously extracted and analyzed in one run within 40 min. The limits of detections (LODs) were among 0.1-10 ng/mL, and good linearity was obtained. Deviations in precision and accuracy were all lower than 15% at three QC levels. This method was then applied to two forensic samples, resulting in information on drinking habits and drinking time which were very useful for the interpretation of the blood alcohol results.

Biomarkers for the Detection of Prenatal Alcohol Exposure: A Review

Alcohol exposure during pregnancy can cause adverse effects to the fetus, because it interferes with fetal development, leading to later physical and mental impairment. The most common clinical tool to determine fetal alcohol exposure is maternal self-reporting. However, a more objective and useful method is based on the use of biomarkers in biological specimens alone or in combination with maternal self-reporting. This review reports on clinically relevant biomarkers for detection of prenatal alcohol exposure (PAE). A systematic search was performed to ensure a proper overview in existing literature. Studies were selected to give an overview on clinically relevant neonatal and maternal biomarkers. The direct biomarkers fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG), ethyl sulfate, and phosphatidylethanol (PEth) were found to be the most appropriate biomarkers in relation to detection of PAE. To review each biomarker in a clinical context, we have compared the advantages and disadvantages of each biomarker, in relation to its window of detectability, ease of collection, and the ease and cost of analysis of each biomarker. The biomarkers PEth, FAEEs, and EtG were found to be applicable for detection of even low levels of alcohol exposure. Meconium is an accessible matrix for determination of FAEEs and EtG, and blood an accessible matrix for determination of PEth.

Assays of Gamma-Glutamyl Transferase and Carbohydrate-Deficient Transferrin Combination from Maternal Serum Improve the Detection of Prenatal Alcohol Exposure

BACKGROUND

Alcohol use during pregnancy leads to detrimental effects on fetal development. As self-reports by mothers are known to be unreliable for assessing prenatal alcohol exposure, there is a need for sensitive and specific biomarkers for identifying those at risk for alcohol-affected offspring.

METHODS

We measured serum gamma-glutamyl transferase (GGT), carbohydrate-deficient transferrin (CDT), a mathematically formulated combination of GGT and CDT (GGT-CDT), and ethylglucuronide (EtG) concentrations from 1,936 mothers with a positive (n = 480) or negative (n = 1,456) history of alcohol use at the time of pregnancy. The material included 385 alcohol-abusing mothers who subsequently gave birth to children with fetal alcohol syndrome (FAS) and 1,551 mothers without FAS children including 95 women who reported a median of 1.0 standard drinks of alcohol per day during pregnancy and 1,456 nondrinking controls. Among those without FAS outcome, there were 405 mothers with gestational diabetes mellitus (GDM) and 745 mothers representing lifelong abstainers.

RESULTS

Mothers of FAS children had higher mean GGT, CDT, GGT-CDT, and EtG levels than abstainers (p < 0.001 for all comparisons) or mothers reporting some alcohol consumption but whose children were not diagnosed with FAS (p < 0.001 for all comparisons). In receiver operating characteristic analyses using cutoffs based on abstainers, the area under the curves (AUCs) for GGT-CDT (0.873) were higher than those of GGT (0.824), CDT (0.776), or EtG (0.584) for differentiating the mothers of FAS children and abstainers. Unlike CDT, this combination marker also differed significantly between drinking mothers without FAS outcome and abstainers (AUC = 0.730, p < 0.001). In comparisons adjusted for GDM and body mass index, the group of mothers who had reported a median of 1.0 standard drinks of alcohol per day during pregnancy also differed from the group reporting no current alcohol intake in GGT (p < 0.02) and GGT-CDT (p < 0.01) levels.

CONCLUSIONS

Combination of GGT and CDT improves the identification of prenatal alcohol exposure and associated high-risk pregnancies. A more systematic use of biomarkers may help intervention efforts to prevent alcohol-induced adverse effects on fetal development.

Quantification of EtG in hair, EtG and EtS in urine and PEth species in capillary dried blood spots to assess the alcohol consumption in driver's licence regranting cases

BACKGROUND

In Belgium, the analysis of indirect biomarkers such as carbohydrate deficient transferrin (CDT%), gamma-glutamyltransferase (GGT), aspartate aminotransferase/alanine aminotransferase (AST/ALT) and mean corpuscular volume (MCV), is currently used to monitor the alcohol consumption in cases of fitness to drive assessment. We evaluated the use of direct ethanol markers for this purpose, exclusively determined in matrices obtained via non- or minimally invasive sampling.

METHODS

Three validated quantitative methods (ethylglucuronide (EtG) in hair and urine, ethylsulfate (EtS) in urine, and phosphatidylethanol species (PEth 16:0/18:1, PEth 18:1/18:1 and PEth 16:0/16:0) in capillary dried blood spots (C-DBS)) were used. Fifty volunteers, for whom fitness to drive had to be assessed and for whom a blood analysis for indirect biomarkers was requested, were included in the study. The sampling and analysis of hair, urine and C-DBS were added to the process currently used.

RESULTS

Hair EtG (24/50) and C-DBS PEths (29/50) are more sensitive than the currently used indirect biomarkers (13/50 for CDT%) to detect excessive and chronic alcohol consumption and allow to disprove an abstinence period. Urinary EtG and EtS are useful parameters to determine recent alcohol consumption.

CONCLUSION

The combined use of the three strategies allows better inference about the evolution of the alcohol consumption prior to the sampling. Moreover, the exclusive use of non- or minimally invasive sampling (hair, urine and C-DBS) allows this to be performed directly during the fitness to drive assessment by regular staff members. This approach offers the potential to improve the Belgian driver's licence regranting process.

Diagnosis of Alcoholic Liver Disease: Key Foundations and New Developments

Alcoholic liver disease is a spectrum of conditions that include alcoholic fatty liver disease, alcoholic hepatitis, and chronic alcoholic liver disease. The diagnosis of alcoholic liver disease remains founded in an accurate patient history and detailed physical examination. Concurrent with the physical examination, objective data from laboratory, imaging, and histologic studies are helpful to confirm a diagnosis of alcoholic liver disease. Novel biomarkers, scoring systems, and imaging modalities are improving the ability to diagnose and manage alcoholic liver disease, but for most practicing clinicians, these have not been adopted widely because of their cost, but also because of limitations and uncertainty in their performance characteristics.