Unlocking the potential of forensic traces: Analytical approaches to generate investigative leads

Forensic investigation involves gathering the information necessary to understand the criminal events as well as linking objects or individuals to an item, location or other individual(s) for investigative purposes. For years techniques such as presumptive chemical tests, DNA profiling or fingermark analysis have been of great value to this process. However, these techniques have their limitations, whether it is a lack of confidence in the results obtained due to cross-reactivity, subjectivity and low sensitivity; or because they are dependent on holding reference samples in a pre-existing database. There is currently a need to devise new ways to gather as much information as possible from a single trace, particularly from biological traces commonly encountered in forensic casework. This review outlines the most recent advancements in the forensic analysis of biological fluids, fingermarks and hair. Special emphasis is placed on analytical methods that can expand the information obtained from the trace beyond what is achieved in the usual practices. Special attention is paid to those methods that accurately determine the nature of the sample, as well as how long it has been at the crime scene, along with individualising information regarding the donor source of the trace.

Determination of Ethyl Glucuronide and Ethyl Sulfate in Human Whole Blood and Vitreous Humor by LC-MS-MS and Applications to the Interpretation of Postmortem Ethanol Findings

Identifying the source of ethanol in a decedent remained a complicated problem for forensic toxicologists because of postmortem ethanol formation. As ethanol's non-oxidative metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS) have the potential to distinguish between antemortem ethanol consumption and postmortem ethanol formation, due to their high sensitivity and selectivity. In the current study, a simple and quick liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for the determination of EtG and EtS in human whole blood and vitreous humor (VH). A total of 20 μL of the sample was precipitated by methanol, and the analytes were detected by LC-MS/MS in a run of 6 min. This method achieved high sensitivity (limits of detection: 2 ng/mL for both EtG and EtS), with linearity in the range of 5-10,000 ng/mL in both whole blood and VH. Deviations in accuracy, inter- and intra-day precision were all lower than 15% at three quality control levels. Subsequently, this method was applied to 62 real forensic cases. Only blood samples were available in 52 cases. Paired blood and VH samples were present in 10 cases. The concentrations of EtG and EtS in blood were in the range of 0-22,264.8 ng/mL and 0-2,126.0 ng/mL, respectively. In one case with both blood and VH, the blood ethanol concentration was 1.22 mg/mL, with EtG and EtS both below limits of quantification (5 ng/mL) in VH, and no EtG and EtS found in whole blood. The results suggested that EtG and EtS were useful markers for the interpretation of ethanol resource in postmortem blood and VH.

A Pilot Study Comparing the Effects of Consuming 100% Orange Juice or Sucrose-Sweetened Beverage on Risk Factors for Cardiometabolic Disease in Women

Overconsumption of sugar-sweetened beverages increases risk factors associated with cardiometabolic disease, in part due to hepatic fructose overload. However, it is not clear whether consumption of beverages containing fructose as naturally occurring sugar produces equivalent metabolic dysregulation as beverages containing added sugars. We compared the effects of consuming naturally-sweetened orange juice (OJ) or sucrose-sweetened beverages (sucrose-SB) for two weeks on risk factors for cardiometabolic disease. Healthy, overweight women (n = 20) were assigned to consume either 3 servings of 100% orange juice or sucrose-SB/day. We conducted 16-hour serial blood collections and 3-h oral glucose tolerance tests during a 30-h inpatient visit at baseline and after the 2-week diet intervention. The 16-h area under the curve (AUC) for uric acid increased in subjects consuming sucrose-SB compared with subjects consuming OJ. Unlike sucrose-SB, OJ did not significantly increase fasting or postprandial lipoproteins. Consumption of both beverages resulted in reductions in the Matsuda insulin sensitivity index (OJ: -0.40 ± 0.18, p = 0.04 within group; sucrose-SB: -1.0 ± 0.38, p = 0.006 within group; p = 0.53 between groups). Findings from this pilot study suggest that consumption of OJ at levels above the current dietary guidelines for sugar intake does not increase plasma uric acid concentrations compared with sucrose-SB, but appears to lead to comparable decreases of insulin sensitivity.

Assessment of recent alcohol consumption by detecting ethyl glucuronide and ethyl sulphate level among traffic accident patients

Objective: This study aims to explain whether EtG and EtS, which are two non-oxidative ethanol metabolites secreted by the liver and used as markers of alcohol intake related to an incident, were also present in whole blood samples of patients with traffic accident injuries.Methods: EtG and EtS concentrations in all of the whole blood samples were sent to the Forensic Medicine Department of Cukurova University for testing Blood Alcohol Concentrations (BAC) via validated liquid chromatography-tandem mass spectrometer method.Results: The scope of the study covers 200 patients that were admitted to medical services within 12 h following the incident. Of all patients 16.5% were found to be BAC positive, while 35.5 and 23.5 were positive for EtG and EtS, respectively. All samples with a positive BAC result were also positive for EtG and EtS.Conclusion: Detection of EtG and EtS, minor metabolites along with ethanol in the blood can serve as an objective tool to provide further analysis regarding alcohol-related traffic accidents at emergency services.

Biomarkers of the alcohol hangover state: Ethyl glucuronide (EtG) and ethyl sulfate (EtS)

INTRODUCTION

The aim of this study was to investigate the usefulness of ethyl glucuronide (EtG) and ethyl sulfate (EtS) as biomarkers of the hangover state.

METHODS

Thirty-sixhealthy social drinkers participated in this study, being of naturalistic design. Eighteen participants experience regular hangovers (the hangover group), whereas the other 18 claim to not experience a hangover (the hangover-immune group). On a control day (alcohol-free) day and a post-alcohol day, urine EtG and EtS concentrations were determined and hangover severity assessed.

RESULTS

Urinary EtG and EtS concentrations were significantly increased on post-alcohol day compared to the control day (p = .0001). Both EtG and EtS concentrations did not significantly correlate with the overall hangover score, nor with the estimated peak blood alcohol concentrations and number of alcoholic drinks. EtG correlated significantly only with the individual hangover symptom "headache" (p = .033; r = .403). No significant correlations were found with the EtG to EtS ratio. EtG and EtS concentrations significantly correlated with urine ethanol concentrations.

CONCLUSIONS

Although urine EtG and EtS concentration did not significantly correlate to estimated peak blood alcohol concentrations or the number of alcoholic drinks consumed, a significant correlation was found with urine ethanol concentration. However, urine EtG and EtS concentrations did not significantly correlate with overall hangover severity.

Value of Ethyl Glucuronide and Ethyl Sulfate in Serum as Biomarkers of Alcohol Consumption

BACKGROUND

Urinary Ethyl glucuronide (EtG) and Ethyl sulfate (EtS) are established markers of alcohol conumption. Measurement of these markers in serum offers certain advantages. This outpatient department based study evaluated performance of serum Ethyl glucuronide (EtG) and Ethyl sulphate (EtS) as biomarkers of recent alcohol consumption in alcohol dependent subjects. It also evaluated effect of alcohol dose and time since consumption on serum EtG and EtS concentration.

METHODS

Information regarding alcohol intake was collected using Time line follow back calendar method from 152 subjects. Blood samples were collected to determine serum EtG and EtS concentration.

RESULTS

The results revealed that serum EtG (at a threshold of 45 ng/mL) could detect recent moderate to heavy alcohol consumption with 85 percent sensitivity and 89 percent specificity. The results also show that simultaneous measurement of EtS does not increase test accuracy. We found that dose of alcohol and time since alcohol consumption explain 68 and 62 percent variance in serum EtG and EtS levels.

CONCLUSION

EtG testing in blood was found useful as a way to detect recent drinking. This sensitive and specific short-term biomarker provides valuable information about recent alcohol consumption.

High resolution metabolomics technology reveals widespread pathway changes of alcoholic liver disease

The current study provides insights into the molecular mechanisms of ALD from widespread pathway changes.

Serum metabolomic profiling in acute alcoholic hepatitis identifies multiple dysregulated pathways

BACKGROUND AND OBJECTIVES

While animal studies have implicated derangements of global energy homeostasis in the pathogenesis of acute alcoholic hepatitis (AAH), the relevance of these findings to the development of human AAH remains unclear. Using global, unbiased serum metabolomics analysis, we sought to characterize alterations in metabolic pathways associated with severe AAH and identify potential biomarkers for disease prognosis.

METHODS

This prospective, case-control study design included 25 patients with severe AAH and 25 ambulatory patients with alcoholic cirrhosis. Serum samples were collected within 24 hours of the index clinical encounter. Global, unbiased metabolomics profiling was performed. Patients were followed for 180 days after enrollment to determine survival.

RESULTS

Levels of 234 biochemicals were altered in subjects with severe AAH. Random-forest analysis, principal component analysis, and integrated hierarchical clustering methods demonstrated that metabolomics profiles separated the two cohorts with 100% accuracy. Severe AAH was associated with enhanced triglyceride lipolysis, impaired mitochondrial fatty acid beta oxidation, and upregulated omega oxidation. Low levels of multiple lysolipids and related metabolites suggested decreased plasma membrane remodeling in severe AAH. While most measured bile acids were increased in severe AAH, low deoxycholate and glycodeoxycholate levels indicated intestinal dysbiosis. Several changes in substrate utilization for energy homeostasis were identified in severe AAH, including increased glucose consumption by the pentose phosphate pathway, altered tricarboxylic acid (TCA) cycle activity, and enhanced peptide catabolism. Finally, altered levels of small molecules related to glutathione metabolism and antioxidant vitamin depletion were observed in patients with severe AAH. Univariable logistic regression revealed 15 metabolites associated with 180-day survival in severe AAH.

CONCLUSION

Severe AAH is characterized by a distinct metabolic phenotype spanning multiple pathways. Metabolomics profiling revealed a panel of biomarkers for disease prognosis, and future studies are planned to validate these findings in larger cohorts of patients with severe AAH.

Prevalence of ethyl glucuronide and ethyl sulphate among patients injured when driving or at work

AIMS

Presence of EtG or EtS among patients injured when driving or at work may indicate that very low BAC or residual effects of alcohol at the time of the accident may be associated with increased accident risk. The aim of this study was to assess: whether the alcohol metabolites EtG and EtS were present in a sample of patients injured when driving or injured at work, even if their blood alcohol concentration was negative; and, if EtG and EtS were present, what characterized these patients.

METHODS

Blood samples from patients admitted for treatment of injuries at a Norwegian emergency department were tested for alcohol, EtG and EtS. All samples were also analysed for medicinal and illicit psychoactive substances.

RESULTS

One hundred and ninety-two injured patients who were admitted <12 h after injury were included in the study. EtG or EtS were the most prevalent substances in the sample (17%), and a substantial proportion of the patients who tested negative for all other substances tested positive for EtG or EtS (8%). These patients were older than the rest of the sample and drank alcohol more often, according to their self-report.

CONCLUSION

EtG and EtS were prevalent among patients injured when driving or injured at work, including patients negative for all other substances. EtG and EtS should be included in future case-control studies of psychoactive substance use among injured patients to investigate the possible association between residual alcohol effects and injuries.

Alcohol: Pharmacology and Disposition

Alcohol is the most common drug detected in forensic cases, is often associated with increased aggression and other disinhibitory behaviors in criminal matters, and frequently contributes to the cause of death in medical examiner cases. Significant adverse effects of alcohol generally manifest at blood alcohol concentrations above 100 mg/dL. In postmortem cases, a number of factors can affect the accuracy of the blood measurement, including site of sampling and putrefactive formation. This paper provides an overview of the pharmacology, pharmacokinetics, and interpretation of alcohol and its concentrations in key specimens, with application to forensic medical cases.

The validity of phosphatidylethanol in dried blood spots of newborns for the identification of prenatal alcohol exposure

BACKGROUND

Accurate identification of prenatal alcohol exposure (PAE) in the newborn period offers an opportunity for early identification of children at risk of future neurocognitive problems and the implementation of interventional approaches earlier in life. PAE newborn screening by measuring phosphatidylethanol in dried blood spot (PEth-DBS) cards is feasible, logistically easier, and more cost-efficient compared with other biomarkers. However, the sensitivity and specificity of this method have yet to be established.

METHODS

This prospective cohort study examined validity of PEth-DBS among 28 infants with PAE and 32 controls relative to maternal self-report and other biomarkers. Pregnant women were recruited from a University of New Mexico clinic and followed to early postpartum period. The composite index, which was based on self-reported measures of alcohol use and allowed to classify subjects into PAE and control groups, was the criterion measure used to estimate sensitivity and specificity of PEth-DBS.

RESULTS

The study included large proportions of patients representing ethnic minorities (7.4% American Indian, 81.7% Hispanic/Latina), low education (54.2% <high school), and unplanned pregnancy (90.0%). No differences in sociodemographic characteristics, smoking or illicit drug use were observed among the study groups. The sensitivity of maternal biomarkers (gamma glutamyltranspeptidase [GGT], % carbohydrate-deficient transferrin [%CDT], urine ethyl glucuronide [UEtG], urine ethyl sulfate [UEtS]) was low (<15%) reflecting a moderate chronic or intermittent binge pattern of drinking in this cohort. PEth-DBS demonstrated 100% specificity and the highest sensitivity (32.1%) compared with other biomarkers. A battery consisting of maternal direct ethanol metabolites (UEtG, UEtS, PEth) and newborn PEth-DBS increased sensitivity to 50% without a substantial drop in specificity (93.8%).

CONCLUSIONS

Newborn PEth-DBS is a highly specific biomarker and can facilitate accurate detection of PAE in conjunction with other biomarkers. Minimal invasiveness, ease of storage and transportation of DBS cards, absence of postcollection synthesis, cost savings, and potential integration with routine newborn screening are all unique advantages of this method.

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.

Comparison of ethyl glucuronide and carbohydrate-deficient transferrin in different body fluids for post-mortem identification of alcohol use

AIMS

Alcohol abuse is a major risk factor for premature death. Confirming the role of alcohol consumption in cause-of-death investigations has, however, remained difficult, due to lack of reliable biomarkers.

METHODS

We compared ethyl glucuronide (EtG) and carbohydrate-deficient transferrin (CDT) assays from serum, urine, cerebrospinal fluid and vitreous humor in a forensic autopsy population with either a positive (n = 38) or negative (n = 22) history of alcohol abuse based on detailed medical and police records and forensic toxicological investigations.

RESULTS

A positive blood alcohol concentration (median 1.15‰, range 0-3.3‰) was found in 26/38 (68%) of the cases with a documented history of alcohol abuse. EtG concentrations (mean ± SD) in urine (339 ± 389 mg/l, P < 0.001), vitreous humor (4.2 ± 4.8 mg/l, P < 0.001), serum (6.9 ± 8.9 mg/l, P < 0.01) and cerebrospinal fluid (1.7 ± 2.7 mg/l, P < 0.01) were significantly higher among the cases with a positive history of alcohol use than those in the alcohol-history negative group, whereas in corresponding comparisons CDT was significantly different only in cerebrospinal fluid (4.3 ± 2.1 vs. 2.3 ± 0.6%, P < 0.05). The highest sensitivities (92%) in detecting ante-mortem alcohol use were obtained for urine and vitreous humor EtG assays.

CONCLUSION

Our data indicate that measurements of EtG in urine or vitreous humor show the highest diagnostic accuracies in post-mortem investigations of excessive alcohol consumption and can be recommended for routine applications.

Demonstration of ethyl glucuronide in dental tissue samples by liquid chromatography/electro-spray tandem mass spectrometry

INTRODUCTION

Ethyl glucuronide (EtG) has been studied in various tissues and body fluid for determination of alcohol intake. However, no study, dealing with EtG analysis in dental tissue, was performed so far. In this study, we aimed to demonstrate EtG levels in dental tissue.

MATERIALS AND METHODS

Michigan Alcohol Screening Test (MAST) was performed to 29 participants. Following the test, cases were divided into three groups as non-hazardous alcohol users, alcohol abusers and 6 controls who verbally declared that they were abstainers. A total of 29 tooth specimens, obtained from participants, was included in the study. These specimens were analyzed using LC/MS/MS.

RESULTS

All of the participants included in the study were male. According to the MAST outcomes 14 of the participants were non-hazardous alcohol users, and 9 were alcohol abusers, while 6 patients verbally declared that they were abstainers. Dental tissue analyses revealed EtG levels ranging between EtG<LOD and 23.39 pg/mg. EtG levels were observed to be <LOD in dental specimens of 6 abstainer cases. A significant correlation was found between EtG levels measured in the dental tissues and MAST outcomes on the statistical analyses (r=0.914).

CONCLUSION

The findings of the present study demonstrated that dental tissue can be used for detection of alcohol intake, using LC/MS/MS.

Guidelines for alcohol screening in adolescent trauma patients: a report from the Pediatric Trauma Society Guidelines Committee

BACKGROUND

Alcohol misuse is an important source of preventable injuries in the adolescent population. While alcohol screening and brief interventions are required at American College of Surgeons-accredited trauma centers, there is no standard screening method. To develop guidelines for testing, we reviewed available evidence regarding adolescent alcohol screening after injury, focusing on the questions of which populations require screening, which screening tools are most effective, and at which time point screening should be performed.

METHODS

A comprehensive PubMed search for articles related to alcoholism, trauma, and screening resulted in 1,013 article abstracts for review. Eighty-five full-length articles were considered for inclusion. Articles were excluded based on study type, location (non-US), year of publication, and nonapplicability to the study questions.

RESULTS

Twenty-six articles met full inclusion criteria. Results support universal screening for alcohol misuse in the adolescent trauma population. Although adolescents 14 years and older are more likely to test positive for alcohol misuse, studies suggest screening may need to start at 12 years or younger. Both survey and biochemical screens can identify at-risk adolescents, with the Alcohol Use Disorders Identification Test and the two-question survey based on the Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition criteria for alcohol-use disorders being the most sensitive surveys available.

CONCLUSION

Injured adolescent trauma patients should be universally screened for alcohol misuse during their hospital visit. To maximize the number of at-risk adolescents targeted for interventions, screening should begin at minimum at 12 years. As no screen identifies all at-risk adolescents, a serial screening method using both biochemical tests and standardized questionnaires may increase screening efficacy.

Preoperative alcohol cessation prior to elective surgery

BACKGROUND

Hazardous drinking has been associated with an increased postoperative complication rate after surgery. Common complications include postoperative infections, cardiopulmonary complications, and bleeding episodes. Preoperative abstinence may to some degree reverse alcohol-induced pathophysiological processes and thus prevent postoperative complications.

OBJECTIVES

To assess the effect of preoperative alcohol cessation interventions on the rate of postoperative complications including mortality in hazardous drinkers. To assess the effect of preoperative alcohol cessation interventions for hazardous drinkers on alcohol use in the postoperative period and in the long term.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 9); Ovid MEDLINE (1966 to September 2011); Ovid EMBASE (1966 to September 2011); CINAHL via EBSCOhost (1982 to September 2011). We combined the MEDLINE search strategy with the Cochrane highly sensitive search strategy, as contained in the Cochrane Handbook for Systematic Reviews of Interventions, to identify randomized controlled trials (RCTs).

SELECTION CRITERIA

We included all randomized controlled trials (RCTs) that evaluated the effects of a preoperative alcohol cessation intervention on postoperative complications or postoperative alcohol consumption, or both, in the short and long term in hazardous drinkers . We excluded intraoperative and postoperative alcohol interventions.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed studies to determine eligibility and extracted data using a tool based on guidance in the Cochrane Handbook for Systematic Reviews of Interventions. Where required, we obtained additional information through collaboration with the original author. We presented the main outcomes as dichotomous variables. Where data were available, we planned to conduct subgroup analyses as well as a sensitivity analysis to explore risk of bias.

MAIN RESULTS

We included two studies which involved 69 patients. Both studies were RCTs evaluating the effect of intensive alcohol cessation interventions including pharmacological strategies for alcohol withdrawal and relapse prophylaxis.Our primary outcome measure was postoperative complications and in-hospital and 30-day mortality. Meta-analysis showed an effect on the overall complication rates (odds ratio (OR) 0.22; 95% confidence interval (CI) 0.08 to 0.61; P = 0.004). There was no significant reduction of in-hospital and 30-day mortality (OR 0.39; 95% CI 0.06 to 2.83; P = 0.35).Secondary outcomes included length of stay and postoperative alcohol use. No significant reduction was found.

AUTHORS' CONCLUSIONS

Based on the finding of two studies, it appears that intensive preoperative alcohol cessation interventions, including pharmacological strategies for relapse prophylaxis and withdrawal symptoms, may significantly reduce postoperative complication rates. No effect was found on mortality rates and length of stay.The effect of preoperative alcohol cessation intervention should be further explored in an effort to reduce the adverse effect of alcohol use on surgical outcomes. The number needed to screen to identify eligible patients for alcohol intervention studies in surgical settings seems to be extremely high. This may indicate that these studies are difficult to perform. Nevertheless, timing, duration and intensity of alcohol cessation interventions need to be subject to further investigation.

Monitoring of the alcohol biomarkers PEth, CDT and EtG/EtS in an outpatient treatment setting

AIMS

To compare the sensitivity of whole blood phosphatidylethanol (PEth) with serum carbohydrate-deficient transferrin (CDT) as biomarkers of current regular alcohol consumption, during outpatient treatment for alcohol-related problems. Urinary ethyl glucuronide (EtG) and ethyl sulfate (EtS), and clinical assessment, were used as complementary estimates of relapse to drinking.

METHODS

Biomarker results for 29 men and 11 women (aged 20-73 years) undergoing voluntary outpatient treatment for harmful alcohol use or dependence were utilized for this evaluation. In connection with visits to the unit, blood and/or urine were sampled for measurement of PEth, EtG and EtS (by liquid chromatography-mass spectrometry), and CDT (%disialotransferrin, by high-pressure liquid chromatography).

RESULTS

The comparison included 326 whole blood, 319 serum (1-82 samples/patient) and 654 urine samples (1-178 samples/patient) collected over ~2 years. At the initial assessment, the total PEth value ranged between 0 and 16.5 µmol/l (mean 2.6) with 70% being above the quantification limit (0.1 µmol/l) and 55% above the reference interval (0.7 µmol/l). Initial CDT values were 0.87-6.9% (mean 2.1) with 35% above the applied reference interval (1.7%). At the final sampling (treatment period up to 21 months), the total PEth value had decreased to 0-5.9 µmol/l (mean 0.6; P = 0.0004) and CDT to 0.87-3.3% (mean 1.3; P = 0.0030). Relapses were detected by PEth alone (43% of cases), by PEth and CDT (38%) and the remainder by EtG/EtS.

CONCLUSION

PEth was the most sensitive biomarker of current regular alcohol consumption. PEth-16:0/18:1, usually being the major subform, was as sensitive as total PEth. PEth, CDT and EtG/EtS are useful complementary tools for objective identification of current drinking and relapse detection.

Ethyl glucuronide

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

Phosphatidylethanol in blood (B-PEth): a marker for alcohol use and abuse

Phosphatidylethanol (PEth) represents a group of glycerophospholipid homologues where ethanol by phospholipase D has been bound at the position that normally contains an amino-alcohol. Since the formation of PEth is specifically dependent on ethanol, the diagnostic specificity of PEth as an alcohol biomarker is theoretically 100%. The half-life of PEth in blood is approximately 4 days. The amount of alcohol consumed correlates to blood concentration of PEth and PEth has been shown to be a more sensitive indicator of alcohol consumption than traditional alcohol markers, such as CDT (carbohydrate-deficient transferrin), GGT (γ-glutamyl transferase), and MCV (mean corpuscular volume) or a combination of these. Almost all clinical data so far available are based on a high performance liquid chromatography (HPLC) method with limited analytical sensitivity. With the advent of methods with considerably higher analytical sensitivity (e.g. mass spectrometric methods), clinical sensitivity will increase correspondingly. The possibility of determining very low concentrations of PEth by new sensitive analytical techniques may, however, have both ethical and legal consequences that have to be considered.

Perioperative management of patients with alcohol, tobacco and drug dependency

PURPOSE OF REVIEW

One in five patients in the perioperative setting has a alcohol use disorder (AUD), one in three patients has a nicotine use disorder (NUD) and one in 10 patients has a drug use disorder (DUD) with a high risk of dependency. Patients with dependencies challenge physicians with various complications within the perioperative setting.

RECENT FINDINGS

Adequate treatment of alcohol, nicotine and drug dependency during the perioperative and intraoperative course requires established screening tools in order to evaluate patients' susceptibility to developing complications. Particularly in these patients, secondary prevention and early treatment is warranted.

SUMMARY

Alcohol, nicotine and drug dependency are very treatable. Numerous effective therapeutic options are available and should be offered to patients. Intensive care treatment can be shortened or even avoided by initiating preventive measures. A multimodal approach includes implementation of screening tools, motivational interviewing, preoperative abstinence, individual anaesthesiological treatment, stress reduction preventing delirium and postoperative infection, prevention and treatment of withdrawal syndrome, replacement therapies and provision of preoperative or postoperative detoxification. The implementation rate is very low and urgently requires strategies for improvement.

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

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

Alcohol biomarkers in applied settings: recent advances and future research opportunities

During the past decade, advances have been made in the identification, development, and application of alcohol biomarkers. This is important because of the unique functions that alcohol biomarkers can serve in various applied settings. To carry out these functions, biomarkers must display several features including validity, reliability, adequacy of temporal window of assessment, reasonable cost, and transportability. During the past two decades, several traditional alcohol biomarkers have been studied in multiple human studies. Meanwhile, several new, promising biomarkers, including various alcohol metabolites and alcohol biosensors, are being explored in human studies. In addition, researchers have explored using biomarkers in combination and using biomarkers in combination with self-reports, resulting in increased sensitivity with little sacrifice in specificity. Despite these advances, more research is needed to validate biomarkers, especially the new ones, in humans. Moreover, recent advances in high-throughput technologies for genomics, proteomics, and metabolomics offer unique opportunities to discover novel biomarkers, while additional research is needed to perfect newly developed alcohol sensors. Development of more accurate biomarkers will help practicing clinicians to more effectively screen and monitor individuals who suffer from alcohol use disorders.

Computer assisted modeling of ethyl sulfate pharmacokinetics

For 12 volunteers of a drinking experiment the concentration-time-courses of ethyl sulfate (EtS) and ethanol were simulated and fitted to the experimental data. The concentration-time-courses were described with the same mathematical model as previously used for ethyl glucuronide (EtG). The kinetic model based on the following assumptions and simplifications: a velocity constant k(form) for the first order formation of ethyl sulfate from ethanol and an exponential elimination constant k(el). The mean values (and standard deviations) obtained for k(form) and k(el) were 0.00052 h(-1) (0.00014) and 0.561 h(-1) (0.131), respectively. Using the ranges of these parameters it is possible to calculate minimum and maximum serum concentrations of EtS based on stated ethanol doses and drinking times. The comparison of calculated and measured concentrations can prove the plausibility of alleged ethanol consumption and add evidence to the retrospective calculation of ethanol concentrations based on EtG concentrations.

Alcohol biomarkers in patients admitted for trauma

BACKGROUND

To assess the value of blood alcohol levels (BAL) and carbohydrate-deficient transferrin (CDT) in trauma patients.

METHODS

A prospective study was conducted among 213 patients admitted to a university hospital after trauma. Outcomes of interest included the development of alcohol withdrawal, infections, respiratory problems, cardiac events, thromboembolism, and length of stay.

RESULTS

The majority (78%) of the trauma patients in the study was males over the age of 18. Seventy-five percent were reported drinking an alcohol-containing beverage in the previous 30 days, 34% had > or =5 heavy drinking days, and 18.7% met current DSM-IV criteria for alcohol abuse and 13.1% current criteria for dependence. Twenty-two percent (n = 48) had a positive BAL and 14% (n = 30) a CDT level >2.5%. Twelve percent (n = 27) of the sample developed alcohol withdrawal and 55% (n = 113) had one or more adverse health events during their hospitalization. The development of alcohol withdrawal was associated with an admission CDT >2.5% (chi(2): 4.77, p < 0.029) and/or a positive BAL (chi(2): 54.01, p < 0.001). The alcohol biomarkers identified 13 male and 3 female high-risk patients (7.4% of the total sample) who denied excessive alcohol use, and who would have been missed if these markers were not used. A composite morbidity trauma score composed of 25 adverse health events was associated with a positive BAL (p < 0.022).

CONCLUSION

The study provides additional empirical evidence that supports the use of BAL in all patients admitted for trauma. The usefulness of CDT in trauma patients remains unclear and will require larger samples in more critically ill patients.

Blood kinetics of ethyl glucuronide and ethyl sulphate in heavy drinkers during alcohol detoxification

Studies of ethyl glucuronide (EtG) blood kinetics have so far been performed on healthy volunteers with ingestion of low to moderate doses of ethanol. These data are not necessarily transferable to heavy drinkers where the consumed doses of ethanol are much higher. The aim of this study was to investigate the pharmacokinetics of EtG and ethyl sulphate (EtS) in blood in heavy drinkers after termination of alcohol ingestion. Sixteen patients from an alcohol withdrawal clinic were included directly after admission. Time of end of drinking, estimated daily intake of ethanol (EDI) and medical history were recorded. Three to five blood samples over 20-43 h were collected from each patient subsequent to admission. The median EDI was 172 g (range 60-564). The first sample was collected median 2.5 h after end of drinking (range 0.5-23.5). Two patients had levels of EtG and EtS below LOQ in all samples, the first collected 19.25 and 23.5 h after cessation of drinking, respectively. Of the remaining 14 patients, one subject, suffering from both renal and hepatic disease, showed concentrations of EtG and EtS substantially higher than the rest of the material. This patient's initial value of EtG was 17.9 mg/L and of EtS 5.9 mg/L, with terminal elimination half lives of 11.9 h for EtG and 12.5 h for EtS. Among the remaining 13 patients, the initial median values were 0.7 g/L (range 0-3.7) for ethanol, 1.7 mg/L (range 0.1-5.9) for EtG and 0.9 mg/L (range 0.1-1.9) for EtS. Elimination occurred with a median half-life of 3.3 h for EtG (range 2.6-4.3) and 3.6 h for EtS (range 2.7-5.4). In conclusion, elimination of EtG in heavy drinkers did not significantly differ from healthy volunteers, and EtS appeared to have similar elimination rate. In the present work, there was one exception to this, and we propose that this could be explained by the patient's renal disease, which would delay excretion of these conjugated metabolites.

A review of the use of ethyl glucuronide as a marker for ethanol consumption in forensic and clinical medicine

Ethyl glucuronide (EtG) is a direct phase-II metabolite of ethanol formed through the UDP-glucuronosyl transferase catalyzed conjugation of ethanol with glucuronic acid. It has been detected in many antemortem and postmortem biological matrices using a variety of analytical methods. Due to its long urinary elimination time, detectability in hair, specificity for ethanol exposure, and low detection limits of assays, the use of EtG has been proposed as a marker of recent ethanol intake in a variety of clinical and legal settings, including medical monitoring for relapse, emergency department patient evaluation, postmortem assessments, and transportation accident investigation. However, challenges associated with factors such as establishing appropriate cut-off levels capable of distinguishing between drinking and nonbeverage sources of ethanol exposure, nonuniform laboratory reporting limits, sample stability, and microbial activity substantially complicate accurate interpretation of results. The following review briefly explores the history, utility, and limitations of EtG in contemporary medical and forensic practice.