Recommendations on the measurement and use of the alcohol consumption biomarker CDT. A position paper from the IFCC Working Group on CDT standardisation

BACKGROUND

Carbohydrate deficient transferrin (CDT) is a biomarker for excessive alcohol consumption utilized in clinical and forensic medicine and workplace testing. Previously, many different analytical methods for CDT were used and the measurand varied considerably, making direct comparison of test results difficult. To end this confusion, the IFCC established a working group on CDT standardisation (WG-CDT) which completed its tasks in 2017.

METHODS

This IFCC position paper by the WG-CDT summarizes state of the art information about the measurand and the analytical methods and gives concise recommendations for its utilization.

RESULTS

The results achieved by the CDT standardisation process led to accuracy improvements in national external quality assessment schemes over the years. A brief review of ROC based comparison studies with the traditional biomarkers (GGT, MCV, ALT and AST) discusses the bias resulting from inadequate study populations. In large groups of the general population the superior diagnostic performance of CDT is confirmed.

CONCLUSION

The relationship between alcohol intake versus resulting CDT is discussed as well as the cutoff and measurement uncertainty. Concerning the application in practice, potential pitfalls are considered and recommendations handling both analytical and preanalytical caveats are given. Finally, some examples of serious misunderstandings in publications about CDT are addressed.

A Community Study of SARS-CoV-2 Detection by RT-PCR in Saliva: A Reliable and Effective Method

Efficient, wide-scale testing for SARS-CoV-2 is crucial for monitoring the incidence of the infection in the community. The gold standard for COVID-19 diagnosis is the molecular analysis of epithelial secretions from the upper respiratory system captured by nasopharyngeal (NP) or oropharyngeal swabs. Given the ease of collection, saliva has been proposed as a possible substitute to support testing at the population level. Here, we used a novel saliva collection device designed to favour the safe and correct acquisition of the sample, as well as the processivity of the downstream molecular analysis. We tested 1003 nasopharyngeal swabs and paired saliva samples self-collected by individuals recruited at a public drive-through testing facility. An overall moderate concordance (68%) between the two tests was found, with evidence that neither system can diagnose the infection in 100% of the cases. While the two methods performed equally well in symptomatic individuals, their discordance was mainly restricted to samples from convalescent subjects. The saliva test was at least as effective as NP swabs in asymptomatic individuals recruited for contact tracing. Our study describes a testing strategy of self-collected saliva samples, which is reliable for wide-scale COVID-19 screening in the community and is particularly effective for contact tracing.

Use of LC-HRMS in full scan-XIC mode for multi-analyte urine drug testing - a step towards a 'black-box' solution?

The influx of new psychoactive substances (NPS) has created a need for improved methods for drug testing in toxicology laboratories. The aim of this work was to design, validate and apply a multi-analyte liquid chromatography-high-resolution mass spectrometry (LC-HRMS) method for screening of 148 target analytes belonging to the NPS class, plant alkaloids and new psychoactive therapeutic drugs. The analytical method used a fivefold dilution of urine with nine deuterated internal standards and injection of 2 μl. The LC system involved a 2.0 μm 100 × 2.0 mm YMC-UltraHT Hydrosphere-C₁₈ column and gradient elution with a flow rate of 0.5 ml/min and a total analysis time of 6.0 min. Solvent A consisted of 10 mmol/l ammonium formate and 0.005% formic acid, pH 4.8, and Solvent B was methanol with 10 mmol/l ammonium formate and 0.005% formic acid. The HRMS (Q Exactive, Thermo Scientific) used a heated electrospray interface and was operated in positive mode with 70 000 resolution. The scan range was 100-650 Da, and data for extracted ion chromatograms used ± 10 ppm tolerance. Product ion monitoring was applied for confirmation analysis and for some selected analytes also for screening. Method validation demonstrated limited influence from urine matrix, linear response within the measuring range (typically 0.1-1.0 μg/ml) and acceptable imprecision in quantification (CV <15%). A few analytes were found to be unstable in urine upon storage. The method was successfully applied for routine drug testing of 17 936 unknown samples, of which 2715 (15%) contained 52 of the 148 analytes. It is concluded that the method design based on simple dilution of urine and using LC-HRMS in extracted ion chromatogram mode may offer an analytical system for urine drug testing that fulfils the requirement of a 'black box' solution and can replace immunochemical screening applied on autoanalyzers. Copyright © 2017 John Wiley & Sons, Ltd.

Acute skin and hair symptoms followed by severe, delayed eye complications in subjects using the synthetic opioid MT-45

BACKGROUND

The introduction of unclassified new psychoactive substances (NPS) on the recreational drugs market through open online sale ('legal highs' or 'Internet drugs') continues unabated and represents a growing health hazard. The use of NPS has resulted in numerous, severe, adverse events and fatalities, due to unintended overdose or unknown toxic side-effects.

OBJECTIVES

To try to find a possible common underlying cause for the skin-hair-eye symptoms complex observed in three men.

METHODS

From late 2013 to mid-2014, three Swedish men aged 23-34 years with a history of recreational drug use independently presented with similar and very remarkable clinical signs, requiring extensive examination and prolonged treatment.

RESULTS

Common clinical signs included hair depigmentation, hair loss, widespread folliculitis and dermatitis, painful intertriginous dermatitis, dry eyes, and elevated liver enzymes. Two of them also showed transverse white Mees' lines (leukonychia striata) on the fingernails and toenails, suggesting a temporary, drug-induced, disorganized keratinization. The clinical signs gradually disappeared over time. However, later on, two developed severe bilateral secondary cataracts requiring surgery. Because drug tests within the Swedish STRIDA project had demonstrated intake of the NPS opioid MT-45 in all patients, this was suspected to be the common causative agent.

CONCLUSIONS

These cases highlight the importance for physicians and health professionals to consider the increasing number of novel, untested recreational drugs, as a potential cause of unusual and otherwise unrecognized clinical signs and symptoms.

Evaluation of the COBAS(®) AmpliPrep/COBAS(®) TaqMan(®) HCV Test, v2.0 and comparison to assays used in routine clinical practice in an international multicenter clinical trial: The ExPECT study

BACKGROUND

The COBAS(®) AmpliPrep(®)/COBAS(®) TaqMan(®) HCV Test, v2.0 (CAP/CTM2) is used for HCV RNA viral load monitoring.

OBJECTIVES

The performance of the CAP/CTM2 was compared to other widely used tests, including a manual version of the assay (the COBAS(®) TaqMan(®) HCV Test, v2.0 for use with the High Pure System, HPS/CTM2) predominantly used during phase III clinical trials for the new direct acting antiviral therapies.

STUDY DESIGN

Low HCV RNA level comparisons were performed across tests (Abbott Realtime HCV Test, ART; COBAS(®) AmpliPrep(®)/COBAS(®) TaqMan(®) HCV Test, v1.0, CAP/CTM1; CAP/CTM2; and HPS/CTM2) using dilutions of the 2nd HCV WHO International Standard. Additionally, the clinical performance of the CAP/CTM2 was evaluated with 421 leftover HCV RNA-positive routine clinical samples.

RESULTS

All quantifiable WHO dilutions were within ±0.3log10IU/mL of the expected results across tests and the analytical sensitivity resulted in a limit of detection of 12IU/mL (95% confidence interval, 10, 15). When clinical samples were tested the results for 87% (367 of 421) of all sample comparisons were within ±0.5log10IU/mL. When low viral load results (25-3500IU/mL) were compared, values obtained by the ART assay were significantly lower (p<0.0001) than those obtained with the CAP/CTM2.

CONCLUSIONS

The new CAP/CTM2 showed good accuracy with comparable sensitivity to comparator assays. The new kit is well-suited for use in the routine diagnostic laboratory, especially for accurate monitoring of patients receiving triple therapy or interferone-free regimens.

Problem drinking in relation to treatment outcome among opiate addicts in methadone maintenance treatment

This study analyzed indicators of alcohol-related problems in opiate addicts before, during, and after leaving methadone maintenance treatment (MMT), in relation to illicit drug use and retention in treatment. The study was based on 204 patients, admitted to MMT for the first time between 1 January 1995 and 31 July 2000, and followed until 31 December 2000. Three measures were used to indicate alcohol use and alcohol-related problems; records of hospital care with an alcohol-related diagnosis, any treatment with alcohol-sensitizing drugs (disulfiram or calcium carbimide) during MMT, and results of the 5-hydroxytryptophol to 5-hydroxyindoleacetic acid ratio (5HTOL/5HIAA) in urine, a sensitive biomarker for recent drinking. Use of illicit drugs was determined by routine urine drug testing. About one third of the patients (n = 69) had a lifetime prevalence of hospital treatment for an alcohol-related diagnosis, 45 of whom had been hospitalized (mean 4.2 stays) prior to the start of MMT. There was a significant association (p<0.05) between the number of alcohol-related diagnoses prior to treatment and a positive 5HTOL/5HIAA test during MMT. The alcohol indicators first became positive on average 1.6 years after admission to treatment, compared with after about 4 months for illicit drugs. Use of cannabis or benzodiazepines was significantly associated with alcohol use. Female methadone patients with indications of alcohol-related problems relapsed more often into illicit drug use than did women without such indications (3.9 vs. 2.5 relapse periods/year; p<0.005), whereas no significant association was found for men. The results of the present study indicate that drinking problems among patients undergoing MMT is associated with an increased risk of relapse into illicit drug use and with discharge from treatment. Concurrent treatment of alcohol-related problems, including systematic monitoring of alcohol use, therefore should be recommended to reduce the risk for relapse into illicit drug use and improve overall treatment outcome in MMT.

Functional and structural characterization of the integrase from the prototype foamy virus

Establishment of the stable provirus is an essential step in retroviral replication, orchestrated by integrase (IN), a virus-derived enzyme. Until now, available structural information was limited to the INs of human immunodeficiency virus type 1 (HIV-1), avian sarcoma virus (ASV) and their close orthologs from the Lentivirus and Alpharetrovirus genera. Here, we characterized the in vitro activity of the prototype foamy virus (PFV) IN from the Spumavirus genus and determined the three-dimensional structure of its catalytic core domain (CCD). Recombinant PFV IN displayed robust and almost exclusively concerted integration activity in vitro utilizing donor DNA substrates as short as 16 bp, underscoring its significance as a model for detailed structural studies. Comparison of the HIV-1, ASV and PFV CCD structures highlighted both conserved as well as unique structural features such as organization of the active site and the putative host factor binding face. Despite possessing very limited sequence identity to its HIV counterpart, PFV IN was sensitive to HIV IN strand transfer inhibitors, suggesting that this class of inhibitors target the most conserved features of retroviral IN-DNA complexes.

The effect of moderate alcohol consumption on adiponectin oligomers and muscle oxidative capacity: a human intervention study

AIMS/HYPOTHESIS

The aim of this study was to investigate whether moderate alcohol consumption increases plasma high molecular weight (HMW) adiponectin and/or muscle oxidative capacity.

MATERIALS AND METHODS

Eleven lean (BMI 18-25 kg/m(2)) and eight overweight (BMI >or=27 kg/m(2)) men consumed 100 ml whisky ( approximately 32 g alcohol) or water daily for 4 weeks in a randomised, controlled, crossover trial. After each treatment period, muscle biopsies and fasting blood samples were collected.

RESULTS

Adiponectin concentrations increased (p < 0.001) by 12.5% after 4 weeks of moderate alcohol consumption. Moderate alcohol consumption tended to increase HMW adiponectin by 57% (p = 0.07) and medium molecular weight adiponectin by 12.5% (p = 0.07), but not low molecular weight (LMW) adiponectin. Skeletal muscle citrate synthase, cytochrome c oxidase and beta-3-hydroxyacyl coenzyme A dehydrogenase (beta-HAD) activity were not changed after moderate alcohol consumption, but an interaction between alcohol consumption and BMI was observed for cytochrome c oxidase (p = 0.072) and citrate synthase (p = 0.102) activity. Among lean men, moderate alcohol consumption tended to increase cytochrome c oxidase (p = 0.08) and citrate synthase activity (p = 0.12) by 23 and 26%, respectively, but not among overweight men. In particular, plasma HMW adiponectin correlated positively with activities of skeletal muscle citrate synthase (r = 0.64, p = 0.009), cytochrome c oxidase (p = 0.59, p = 0.009) and beta-HAD (r = 0.46, p = 0.056), while such correlation was not present for LMW adiponectin. Whole-body insulin sensitivity and intramyocellular triacylglycerol content were not affected by moderate alcohol consumption.

CONCLUSIONS/INTERPRETATION

Moderate alcohol consumption increases adiponectin concentrations, and in particular HMW adiponectin. Concentrations of HMW adiponectin in particular were positively associated with skeletal muscle oxidative capacity.

Dynamin 2 is required for the enhancement of HIV-1 infectivity by Nef

Nef is a virulence factor of HIV-1 and other primate lentiviruses that is crucial for rapid progression to AIDS. In cell culture, Nef increases the infectivity of HIV-1 progeny virions by an unknown mechanism. We now show that dynamin 2 (Dyn2), a key regulator of vesicular trafficking, is a binding partner of Nef that is required for its ability to increase viral infectivity. Dominant-negative Dyn2 or the depletion of Dyn2 by small interfering RNA potently inhibited the effect of Nef on HIV-1 infectivity. Furthermore, in Dyn2-depleted cells, this function of Nef could be rescued by ectopically expressed Dyn2 but not by Dyn1, a closely related isoform that does not bind Nef. The infectivity enhancement by Nef also depended on clathrin, because it was diminished in clathrin-depleted cells and profoundly inhibited in cells expressing the clathrin-binding domain of AP180, which blocks clathrin-coated pit formation but not clathrin-independent endocytosis. Together, these findings imply that the infectivity enhancement activity of Nef depends on Dyn2- and clathrin-mediated membrane invagination events.

Comparison of self-reported alcohol intake with the urinary excretion of 5-hydroxytryptophol:5-hydroxyindole-3-acetic acid, a biomarker of recent alcohol intake

Under-reporting of alcohol intake has been frequently reported. However, due to the lack of an objective reference method, e.g. a biomarker, information about the extent of under-reporting of alcohol intake obtained with dietary assessment instruments is not available. The objective of this study was to compare reported alcohol intake data derived from a 24 h recall with a biomarker of recent alcohol intake, the urinary excretion of 5-hydroxytryptophol (5-HTOL):5-hydroxyindole-3-acetic acid (5-HIAA). Embedded into the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam Study, Germany, a validation study that collected 24 h recall data and 24 h urine samples was conducted. Cohort study participants (n107) volunteered to participate in this validation study. Among them were five subjects who reported no consumption of alcoholic beverages but had a 5-HTOL:5-HIAA ratio that indicated recent alcohol intake when the clinical cut-off point was taken as a judging criterion. After exclusion of these under-reporters, the Pearson's correlation coefficient between reported alcohol intake and the 5-HTOL:5-HIAA ratio was 0.92 (P<0.0001). Except for low alcohol intake of <0.1 g/kg body mass, a significant increase in 5-HTOL:5-HIAA excretion was observed with increasing amounts of alcohol intake. In conclusion, the 5-HTOL:5-HIAA excretion ratio appears to be a valuable quantitative biomarker of recent alcohol consumption. Denial of alcohol intake can be detected, but for the quantification of under-reporting of alcohol intake 24 h reference data are not yet available. With these data at hand, however, 5-HTOL:5-HIAA could become a biomarker for validation purposes in nutritional epidemiology.

Mucosal and systemic immune responses in patients with diarrhea due to CS6-expressing enterotoxigenic Escherichia coli

Colonization factor CS6 expressed by enterotoxigenic Escherichia coli (ETEC) is a nonfimbrial polymeric protein. A substantial proportion of ETEC strains isolated from patients in endemic settings and in people who travel to regions where ETEC is endemic are ETEC strains expressing CS6, either alone or in combination with fimbrial colonization factor CS5 or CS4. However, relatively little is known about the natural immune responses elicited against CS6 expressed by ETEC strains causing disease. We studied patients who were hospitalized with diarrhea (n = 46) caused by CS6-expressing ETEC (ETEC expressing CS6 or CS5 plus CS6) and had a disease spectrum ranging from severe dehydration (27%) to moderate or mild dehydration (73%). Using recombinant CS6 antigen, we found that more than 90% of the patients had mucosal immune responses to CS6 expressed as immunoglobulin (IgA) antibody-secreting cells (ASC) or antibody in lymphocyte supernatant (ALS) and that about 57% responded with CS6-specific IgA antibodies in feces. More than 80% of the patients showed IgA seroconversion to CS6. Significant increases in the levels of anti-CS6 antibodies of the IgG isotype were also observed in assays for ASC (75%), ALS (100%), and serum (70%). These studies demonstrated that patients hospitalized with the noninvasive enteric pathogen CS6-expressing ETEC responded with both mucosal and systemic antibodies against CS6. Studies are needed to determine if the anti-CS6 responses protect against reinfection and if protective levels of CS6 immunity are induced by vaccination.

Blood-borne factors possibly associated with post-operative nausea and vomiting: an explorative study in women after breast cancer surgery

BACKGROUND

The pathophysiology behind post-operative nausea and vomiting (PONV) is still not fully understood, especially with respect to gender. According to PONV risk scores, female gender is the strongest predictor for PONV. The risk for PONV after general anaesthesia for breast cancer surgery is 50-80%. The aim of the present explorative study was to identify blood-borne factors that might be associated with the development of PONV in women undergoing breast cancer surgery as a basis for further studies.

METHODS

Fifty patients were enrolled prospectively in the study. A standardized sevoflurane-based anaesthetic was used. Blood samples for the analysis of vasopressin, gastrin, cholecystokinin, epinephrine, norepinephrine, dopamine, serotonin, platelet count and blood glucose were taken at six pre-determined time points peri-operatively, and PONV was assessed during 24 h.

RESULTS

PONV was found in 27 of 47 patients completing the study. Patients with PONV had a larger variability of the platelet count (P = 0.001), a reduced platelet count on the first post-operative day (P = 0.02) and a less pronounced relationship between the platelet count and whole blood serotonin (P = 0.004) compared with non-PONV patients. A lack of a decrease in epinephrine levels in response to the induction of anaesthesia (P = 0.03) and increased levels of vasopressin (P < 0.001), epinephrine (P = 0.005) and blood glucose (P = 0.004) were observed in the early post-operative period in PONV patients.

CONCLUSION

Three different platelet-associated factors and an altered epinephrine pattern were found to be associated with the occurrence of PONV after breast cancer surgery.

Protective immunoglobulin A and G antibodies bind to overlapping intersubunit epitopes in the head domain of type 1 reovirus adhesin sigma1

Nonfusogenic mammalian orthoreovirus (reovirus) is an enteric pathogen of mice and a useful model for studies of how an enteric virus crosses the mucosal barrier of its host and is subject to control by the mucosal immune system. We recently generated and characterized a new murine immunoglobulin A (IgA)-class monoclonal antibody (MAb), 1E1, that binds to the adhesin fiber, sigma1, of reovirus type 1 Lang (T1L) and thereby neutralizes the infectivity of that strain in cell culture. 1E1 is produced in hybridoma cultures as a mixture of monomers, dimers, and higher polymers and is protective against peroral challenges with T1L either when the MAb is passively administered or when it is secreted into the intestines of mice bearing subcutaneous hybridoma tumors. In the present study, selection and analysis of mutants resistant to neutralization by 1E1 identified the region of T1L sigma1 to which the MAb binds. The region bound by a previously characterized type 1 sigma1-specific neutralizing IgG MAb, 5C6, was identified in the same way. Each of the 15 mutants isolated and analyzed was found to be much less sensitive to neutralization by either 1E1 or 5C6, suggesting the two MAbs bind to largely overlapping regions of sigma1. The tested mutants retained the capacity to recognize specific glycoconjugate receptors on rabbit M cells and cultured epithelial cells, even though viral binding to epithelial cells was inhibited by both MAbs. S1 sequence determinations for 12 of the mutants identified sigma1 mutations at four positions between residues 415 and 447, which contribute to forming the receptor-binding head domain. When aligned with the sigma1 sequence of reovirus type 3 Dearing (T3D) and mapped onto the previously reported crystal structure of the T3D sigma1 trimer, the four positions cluster on the side of the sigma1 head, across the interface between two subunits. Three such interface-spanning epitopes are thus present per sigma1 trimer and require the intact quaternary structure of the head domain for MAb binding. Identification of these intersubunit epitopes on sigma1 opens the way for further studies of the mechanisms of antibody-based neutralization and protection with type 1 reoviruses.

Secretory immunoglobulin A antibodies against the sigma1 outer capsid protein of reovirus type 1 Lang prevent infection of mouse Peyer's patches

Reovirus type 1 Lang (T1L) adheres to M cells in the follicle-associated epithelium of mouse intestine and exploits the transport activity of M cells to enter and infect the Peyer's patch mucosa. Adult mice that have previously cleared a reovirus T1L infection have virus-specific immunoglobulin G (IgG) in serum and IgA in secretions and are protected against reinfection. Our aim in this study was to determine whether secretory IgA is sufficient for protection of Peyer's patches against oral reovirus challenge and, if so, against which reovirus antigen(s) the IgA may be directed. Monoclonal antibodies (MAbs) of the IgA isotype, directed against the sigma1 protein of reovirus T1L, the viral adhesin, were produced and tested along with other, existing IgA and IgG MAbs against reovirus T1L outer capsid proteins. Anti-sigma1 IgA and IgG MAbs neutralized reovirus T1L in L cell plaque reduction assays and inhibited T1L adherence to L cells and Caco-2(BBe) intestinal epithelial cells in vitro, but MAbs against other proteins did not. Passive oral administration of anti-sigma1 IgA and IgG MAbs prevented Peyer's patch infection in adult mice, but other MAbs did not. When anti-sigma1 IgA and IgG MAbs were produced in mice from hybridoma backpack tumors, however, the IgA prevented Peyer's patch infection, but the IgG did not. The results provide evidence that neutralizing IgA antibodies specific for the sigma1 protein are protective in vitro and in vivo and that the presence of these antibodies in intestinal secretions is sufficient for protection against entry of reovirus T1L into Peyer's patches.

Biological markers in alcoholism

Alcohol biomarkers include tests indicative of acute or chronic alcohol consumption (state markers), and markers of a genetic predisposition to develop alcohol dependence after chronic exposure (trait markers). While a comprehensive trait marker for alcohol dependence has not been identified, a number of successful state markers for monitoring drinking status are used clinically. These tests provide direct or indirect ways to estimate the amounts of alcohol consumed and the duration of ingestion, and to detect any harmful effects on body functions resulting from long-term misuse. The most obvious method to prove recent drinking is by demonstrating the presence of ethanol in body fluids or breath, but, because ethanol is cleared fairly rapidly from the body, this method is limited to detect only very recent drinking. Measurement of urinary 5-hydroxytryptophol or ethyl glucuronide provide more sensitive methods to disclose recent drinking, because their washout constants are much longer than for ethanol. The liver functions test (GGT, AST and ALT in serum) and the mean corpuscular volume of erythrocytes (MCV) are among the standard diagnostic tools used to identify chronic alcohol exposure. The main disadvantage with these measures is that they have low sensitivity for recent excessive intake, and that raised levels may result from several causes besides heavy drinking, implying a low specificity for alcohol. Carbohydrate-deficient transferrin (CDT), which refers to changes in the carbohydrate composition of serum transferrin, is a more specific marker for identifying excessive alcohol consumption and monitoring abstinence during outpatient treatment. The alcohol biomarkers improves knowledge of drinking patterns in both individuals and populations, and they are also valuable tools for the objective evaluation of treatment efforts. Alcohol markers have, for example, found uses in early identification of at-risk and harmful drinking, and they help to monitor abstinence and relapse in response to outpatient treatment.

The viral sigma1 protein and glycoconjugates containing alpha2-3-linked sialic acid are involved in type 1 reovirus adherence to M cell apical surfaces

Type 1 reoviruses invade the intestinal mucosa of mice by adhering selectively to M cells in the follicle-associated epithelium and then exploiting M cell transport activity. The purpose of this study was to identify the apical cell membrane component and viral protein that mediate the M cell adherence of these viruses. Virions and infectious subviral particles of reovirus type 1 Lang (T1L) adhered to rabbit M cells in Peyer's patch mucosal explants and to tissue sections in an overlay assay. Viral adherence was abolished by pretreatment of sections with periodate and in the presence of excess sialic acid or lectins MAL-I and MAL-II (which recognize complex oligosaccharides containing sialic acid linked alpha2-3 to galactose). The binding of T1L particles to polarized human intestinal (Caco-2(BBe)) cell monolayers was correlated with the presence of MAL-I and MAL-II binding sites, blocked by excess MAL-I and -II, and abolished by neuraminidase treatment. Other type 1 reovirus isolates exhibited MAL-II-sensitive binding to rabbit M cells and polarized Caco-2(BBe) cells, but type 2 or type 3 isolates including type 3 Dearing (T3D) did not. In assays using T1L-T3D reassortants and recoated viral cores containing T1L, T3D, or no sigma1 protein, MAL-II-sensitive binding to rabbit M cells and polarized Caco-2(BBe) cells was consistently associated with the T1L sigma1. MAL-II-recognized oligosaccharide epitopes are not restricted to M cells in vivo, but MAL-II immobilized on virus-sized microparticles bound only to the follicle-associated epithelium and M cells. The results suggest that selective binding of type 1 reoviruses to M cells in vivo involves interaction of the type 1 sigma1 protein with glycoconjugates containing alpha2-3-linked sialic acid that are accessible to viral particles only on M cell apical surfaces.

Ethyl glucuronide concentrations in two successive urinary voids from drinking drivers: relationship to creatinine content and blood and urine ethanol concentrations

The concentrations of alcohol in blood (BAC) and two successive urine voids (UAC) from 100 drunk drivers were compared with the concentration of ethyl glucuronide (EtG), a minor metabolite of ethanol in urine, and the urinary creatinine content as an indicator of dilution. The subjects consisted of 87 men with mean age 42.2+/-14.2 years (+/-standard deviation, S.D.) and 13 women with mean age 42.5+/-14.4 years. Ethanol was measured in blood and urine by headspace gas chromatography (GC) and EtG was determined in urine by liquid chromatography-mass spectrometry (LC-MS). The mean UAC was 2.53+/-1.15g/l for first void compared with 2.35+/-1.17g/l for second void, decreasing by 0.18+/-0.24g/l on average (P<0.001 in paired t-test). The ratios of UAC/BAC were 1.35+/-0.25 for first void and 1.20+/-0.16 for second void and the difference of 0.15+/-0.27 was statistically significant (P<0.001). The UAC/BAC ratio was not correlated with creatinine content of the urine specimens, whereas the concentration of urinary EtG was positively correlated with creatinine (r=0.64 for first void and r=0.62 for second void). The UAC was not correlated with urinary EtG directly (r=-0.03 for first void and r=0.08 for second void) but after adjusting for the relative dilution of the specimens (EtG/creatinine ratio) statistically significant positive correlations were obtained (r=0.58 for first void and r=0.57 for second void). The dilution of the urine, as reflected in creatinine content, is important to consider when EtG measurements are interpreted. The excretion of EtG in urine, like glucuronide conjugates of other drugs, is influenced by diuresis. EtG represents a sensitive and specific marker of acute alcohol ingestion with applications in clinical and forensic medicine.

The effect of total body water on the relationship between alcohol consumption and carbohydrate-deficient transferrin

BACKGROUND

Clinicians agree that alcoholism commonly is overlooked in their patients, and that treating the symptoms without directing therapy to the underlying cause at best delays an inevitable decline in the patient's general health and well-being. The current analysis focused on carbohydrate-deficient transferrin (CDT), a promising biological marker of dangerous alcohol consumption.

METHODS

Included in our study were men (730) and women (613) from study sites in Canada, Brazil, and Japan. All subjects were participants in the WHO/ISBRA Study on State and Trait Markers of Alcoholism, who completed an extensive demographic, medical, and behavioral survey and provided blood samples for determination of CDT levels. ANOVA and chi2 test for equality were used to examine the effect of total body water (TBW) on the alcohol consumption/CDT relationship. To examine whether accounting for differences in TBW improved the diagnostic properties of CDT when used as a state marker for alcohol consumption, odds ratios were calculated for men and women separately.

RESULTS

Our results show that accounting for individual differences in TBW significantly influenced the alcohol consumption/CDT dose-response relationship. The effect of TBW was different for men compared with women. When we used a consumption cutoff value of 40 g/day and the CDTect recommended cutoffs (20 for men; 27 for women), adjusting for differences in TBW significantly increased diagnostic performance of CDT in men but not women.

CONCLUSIONS

The dependence of CDT measures on body water content needs to be taken into account to maximize the performance of CDT as an effective state marker of alcohol consumption in males.

An outbreak of gastroenteritis in Osaka, Japan due to Escherichia coli serogroup O166:H15 that had a coding gene for enteroaggregative E. coli heat-stable enterotoxin 1 (EAST1)

In an outbreak of gastroenteritis on 23 July 1996, in Osaka, Japan, 54 of 91 persons who had attended a meeting the previous day became ill. Escherichia coli O166:H15 was isolated from stool specimens of patients (29/33, 88%). Laboratory tests for other bacterial pathogens and viruses were negative. The E. coli 0166 organisms did not adhere to HEp-2 cells in a localized, diffuse, or enteroaggregative manner. The organisms did not express known enterotoxigenic E. coli (ETEC) colonization factors. In polymerase chain reaction tests, the bacteria did not have coding genes for shigatoxin of enterohemorrhagic E. coli (EHEC), heat-labile, or heat-stable enterotoxin of ETEC, attachment and effacement (eaeA) of EPEC, or invasion (invE) of enteroinvasive E. coli (EIEC). Consequently, they could not be assigned to any of the recognized diarrhoeagenic groups of E. coli: EPEC, ETEC, EHEC, EIEC, enteroaggregative E. coli (EAggEC), or diffusely adhering E. coli. However, the organisms possessed the EAggEC heat-stable enterotoxin (EAST1) gene. To our knowledge, this is the first report of an outbreak caused by E. coli that did not have well-characterized virulence genes other than EAST1. The isolates showed the same DNA banding pattern in pulsed-field gel electrophoresis after digestion with the restriction enzymes XbaI or NotI. Three O166:H15 strains isolated from two sporadic cases and another outbreak during 1997-8 were distinct, indicating that multiple clones have spread already. We propose that diarrhoeal specimens should be examined for E. coli possessing the EAST1 gene.

Study of Axis-Shield new %CDT immunoassay for quantification of carbohydrate-deficient transferrin (CDT) in serum

Carbohydrate-deficient transferrin (CDT) in serum has emerged as a useful biochemical marker for identifying current alcohol misuse and monitoring abstinence. This study evaluated the performance of Axis-Shield new %CDT turbidimetric immunoassay (TIA; microtitre and Cobas Mira applications). Comparison was made with the previous Axis %CDT-TIA immunoassay (reference value <5.5%) and %CDT with the high-performance liquid chromatography (HPLC) technique (reference value <1.2%). The new %CDT assay measures primarily the asialo, monosialo and disialo transferrin isoforms, and the result is expressed as the amount relative to total transferrin. The analytical precision (coefficient of variation: CV) of the %CDT assay ranged between 3.1 and 8.5% for kit controls and serum samples. The %CDT values in serum from healthy social drinkers [i.e. Alcohol Use Disorders Identification Test (AUDIT) score 1-7 for men, and 1-5 for women] were 2.07 +/- 0.37% (mean +/- SD, range 1.4-3.3%, n = 100) and this was not significantly different from healthy non-drinkers (1.88 +/- 0.43%, 1.3-2.9%, n = 14), whereas abstinent alcohol patients showed slightly higher values (2.26 +/- 0.41, 1.7-3.4, n = 25). In chronic heavy drinkers (mean daily intake 225 +/- 137 g ethanol according to self-report), the %CDT values were markedly increased (6.33 +/- 4.01%, 1.2-18.0%, n = 107). There was no significant difference in %CDT values between male and female social drinkers. The reference value of the new %CDT assay to be used in clinical practice was tentatively set at <3.0%, which is slightly higher than that obtained by receiver operating characteristics (ROC) curve analysis (<2.8%) and that proposed by the manufacturer in the Instruction Manual (<2.6%). The %CDT assay showed good overall correlation with %CDT-TIA (r = 0.986, P < 0.0001) and %CDT-HPLC (r = 0.978, P < 0.0001). The specificity of the %CDT assay in healthy social drinkers was 98% (%CDT-TIA 100%, %CDT-HPLC 99%) and the sensitivity for any drinking during last week in the alcohol patients was 75% (%CDT-TIA 71%, %CDT-HPLC 80%). The new Axis-Shield %CDT assay can be recommended for routine use. However, whenever a positive immunoassay test result could lead to serious consequences for the individual, it is recommended to confirm the CDT result by the HPLC technique.

Interference of transferrin isoform types with carbohydrate-deficient transferrin quantification in the identification of alcohol abuse

BACKGROUND

Isoforms of transferrin interfere with measurement of carbohydrate-deficient transferrin (CDT) as a marker of heavy alcohol consumption. We evaluated the rate of inaccurate CDT results by immunoassays.

METHODS

We studied 2360 consecutive sera (1614 individuals) submitted for CDT assay without clinical information as well as samples from 1 patient with a congenital disorder of glycosylation (CDG Ia) and from 6 healthy carriers of CDG Ia. The CDTect, %CDT-TIA, and new %CDT immunoassays were compared with HPLC (%CDT-HPLC). Transferrin isoform pattern were evaluated by isoelectric focusing (IEF).

RESULTS

Transferrin BC and CD heterozygotes were found at frequencies of approximately 0.7% and approximately 0.2%, respectively. Another transferrin C subtype, where di- and trisialotransferrin partly coeluted (tentatively identified as C2C3), was observed in approximately 0.6%. Compared with the %CDT-HPLC method, the immunoassays often produced low results for transferrin BC and high results for transferrin CD and "C2C3". A very high trisialotransferrin value (frequency approximately 1%) often produced high CDT immunoassay results. In four of six healthy carriers of CDG Ia, a- and disialotransferrin were highly increased and the HPLC and IEF isoform patterns were indistinguishable from those in alcohol abuse.

CONCLUSIONS

Rare transferrin isoform types and abnormal amounts of trisialotransferrin (total frequency approximately 2-3%) may cause incorrect determination of CDT with immunoassays. The observed variants were readily identified by HPLC and IEF, which can be recommended for verification of CDT immunoassay results in doubtful cases. In healthy carriers of CDG Ia, CDT is high by all assays.

WHP/ISBRA study on state and trait markers in alcoholism

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chair was Boris Tabakoff. The presentations were (1) Overview of the WHO/ISBRA study on state and trait markers in alcoholism, by Boris Tabakoff; (2) Biochemical markers of acute and chronic drinking: Results of the WHO/ISBRA study, by Anders Helander; (3) The impact of country of recruitment and body mass index on biological marker dose-response curves in the WHO/ISBRA Study, by Kate M. Conigrave; (4) Relationship of body water to carbohydrate-deficient transferrin measures, by Larry Martinez; and (5) Platelet adenylyl cyclase activity as a trait marker of alcohol dependence, by Paula L. Hoffman.

Perioperative morbidity and mortality in chronic alcoholic patients

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Claudia Spies and Hanne Tønnesen. The presentations were (1) Relevance of alcohol misuse in surgical patients, by Hanne Tønnesen; (2) Diagnosis of alcohol abuse and alcohol dependence, by Sven Andreasson; (3) Diagnosis of acute alcohol misuse, by Anders Helander; (4) Preoperative intervention for excessive alcohol consumption, by Kate Conigrave; and (5) Prevention and treatment of perioperative complications in chronic alcoholics, by Claudia Spies.

[CDT a valuable marker of overconsumption of alcohol. Guidelines for its use in connection with automobile driver examination]

According to the medical regulations for obtaining a driver's license in Sweden, alcohol abuse/dependency constitutes sufficient grounds for denial. In the case of a conviction for gross drunk driving, it is incumbent upon the offender to present a medical certificate verifying a "sober lifestyle". Biological markers are important tools for proving alcohol abuse in each of these contexts. In this connection, CDT analyses play a key role through their high marked specificity for increased alcohol consumption. The authors have agreed upon the guidelines as presented in this paper for determining sobriety as it pertains to possession of a driver's license. Special emphasis is placed on how CDT tests should be used and interpreted in such contexts, as well as their value as evidence in the case of increased CDT levels.

Misleading results of ethanol analysis in urine specimens from rape victims suffering from diabetes

We report appreciably high concentrations of ethanol (82 and 102 mg/dL) in specimens of urine collected from two victims of date rape. Both girls (aged 15 and 18 years) suffered from diabetes mellitus, but adamantly denied drinking any alcohol before or after the incident. The presence of glycosuria and high risk of fungal infections in female diabetics suggests that ethanol was produced in vitro by fermentation after voiding. Making a routine test for sugar in the urine and ensuring that the sampling tubes contain sufficient sodium or potassium fluoride to inhibit glycolysis are recommended practices. A specific marker for post-sampling synthesis of ethanol might also be used such as the 5HTOL/5HIAA ratio.

Dietary serotonin and alcohol combined may provoke adverse physiological symptoms due to 5-hydroxytryptophol

The urinary excretion products of serotonin (5-hydroxytryptamine, 5HT) are 5-hydroxyindole-3-acetic acid (5HIAA) and 5-hydroxytryptophol (5HTOL), and the ratio of 5HTOL to 5HIAA is normally very low (< 0.01 ) in man. Intake of foods rich in 5HT (high amounts in banana, pineapple, and walnuts) induces a general increase in the output of 5HT metabolites, without affecting the 5HTOL/5HIAA ratio. In contrast, during metabolism of ethanol there is a shift in the catabolic pattern of 5HT, and the formation of 5HTOL increases appreciably at the expense of 5HIAA. Accordingly, the urinary 5HTOL/ 5HIAA ratio increases and does not recover to baseline levels until several hours after ethanol has been cleared from the body. When 10 healthy subjects ingested a moderate dose of ethanol (0.5 g/kg), the urinary 5HTOL/SHIAA ratio was increased approximately 70-fold on average at 4 h after intake. When the same amount of ethanol was ingested together with 3 bananas (approximately 10 mg 5HT), this ratio was increased approximately 100-fold at 4 h and still significantly higher than baseline levels at 24 h. Starting at 3-4 h after the combined intake of ethanol and banana, 7 subjects experienced one or more unpleasant symptoms (diarrhea, headache, and fatigue) which are associated with the 5HT system. The events were transient but typically lasted for several hours, and the duration correlated with the time period during which 5HTOL levels were raised. Intake of ethanol and banana separately produced much lower increases in 5HTOL output and caused no corresponding effects. This observation indicate that dietary 5HT intake together with even a moderate dose of ethanol can provoke unpleasant physiological symptoms. The symptoms may be attributed to the high concentration of 5HTOL.

Human antibody response to longus type IV pilus and study of its prevalence among enterotoxigenic Escherichia coli in Bangladesh by using monoclonal antibodies

Mouse monoclonal antibodies (MAbs) were derived against longus (CS20), a type IV pilus expressed by human enterotoxigenic Escherichia coli (ETEC). One MAb (ICA39) detected longus in 56 (8.5%) of 662 ETEC isolates obtained from a routine surveillance of diarrheal stools from children and adults. Five patients with diarrhea from whom longus-positive ETEC were isolated were also recruited. Of these 61 isolates, 50 were positive for other colonization factors (CFs; 61% for CFA/II and 21% for CFA/I), and 11 were negative for any of the other 8 CFs that were tested. They were either positive for the heat-stable enterotoxin (ST; n=29) or for the heat-labile enterotoxin (LT) and ST (n=32). All longus-positive ETEC were confirmed by polymerase chain reaction to harbor lngA, the longus structural pilin gene. Sera and/or fecal extracts from the patients reacted with the 22-kDa pilin polypeptide in immunoblots and ELISA. These studies show that longus is prevalent among ETEC in Bangladesh and that longus gives rise to IgA antibody responses in patients.

Platelet adenylyl cyclase activity as a trait marker of alcohol dependence. WHO/ISBRA Collaborative Study Investigators. International Society for Biomedical Research on Alcoholism

BACKGROUND

There is compelling evidence that genetic factors play a major role in the development of alcohol dependence. Platelet adenylyl cyclase (AC) activity has been proposed as a biochemical marker for differentiating alcohol-dependent and nondependent subjects, but the sensitivity and specificity of this marker have not been ascertained. The objective of this study was to determine the sensitivity and specificity of platelet AC activity in identifying alcohol-dependent subjects and to ascertain the effect of medical/ psychiatric variables, drinking and smoking history, and age and body weight on AC activity.

METHODS

The cross-sectional study was conducted from 1995 to 1998. Participants were 210 Australian White men who were community volunteers and alcohol treatment inpatients in Sydney, Australia. There were 41 nondrinkers, 140 drinkers, and 29 men who were entering alcohol treatment. The main outcome measure was platelet AC activity. Classification variables were plasma ethanol, gamma-glutamyltransferase, aspartate aminotransferase, serum carbohydrate-deficient transferrin (CDT), and urinary 5-hydroxytryptophol/5-hydroxyindoleacetic acid (5-HTOL/5-HIAA) levels, and World Health Organization/International Society for Biomedical Research on Alcoholism Interview Schedule variables, which included alcohol use and dependence criteria.

RESULTS

Among subjects who reported abstinence for at least 4 days, both cesium fluoride (CsF)- and forskolin-stimulated platelet AC activities were significantly lower in those with a lifetime history of alcohol dependence compared with those with no such history (p < 0.005 and p < 0.05, respectively). The sensitivity and specificity of CsF-stimulated AC activity to discriminate individuals with a lifetime history of alcohol dependence were 75% and 79%, respectively. Similar values for sensitivity and specificity for CsF-stimulated AC activity were calculated when discriminating current alcohol dependence in the subjects in our sample. Irrespective of the history of alcohol dependence, persons who had consumed alcohol recently (within the last 3-4 days) showed significantly higher mean basal, CsF-stimulated, and forskolin-stimulated AC activity (p < 0.001), as did those who had elevated 5-HTOL/5-HIAA ratios or CDT levels, indicative of recent (heavy) drinking. The "normalization" of platelet AC activity to baseline levels after an individual stops drinking may be related to the generation of new platelets during the abstinence period. Conduct disorder and antisocial personality disorder were not associated with low AC activity, but low forskolin-stimulated AC activity was associated with major depression.

CONCLUSIONS

We found that CsF- and forskolin-stimulated platelet AC activity discriminates between subjects with and without alcohol dependence in a population of subjects who had not consumed significant quantities of ethanol recently. Recent alcohol consumption is a confounding variable that can alter the measured levels of AC activity. Forskolin-stimulated platelet AC activity also may be influenced by a history of major depression.

Studies on the interaction between ethanol and serotonin metabolism in rat, using deuterated ethanol and 4-methylpyrazole

The metabolic interaction between ethanol and serotonin (5-hydroxytryptamine) via alcohol dehydrogenase (ADH; EC 1.1.1.1) was studied in tissue homogenates of Sprague-Dawley rats by following the transfer of deuterium from deuterated ethanol over endogenous NADH to 5-hydroxytryptophol (5HTOL). Homogenates of whole brain, lung, spleen, kidney, liver, stomach, jejunum, ileum, colon, and caecum were incubated in the presence of [2H2]ethanol and 5-hydroxyindole-3-acetaldehyde (5HIAL), and the [2H]5HTOL formed was identified and quantified using gas chromatography-mass spectrometry. ADH activity was most abundant in liver, kidney, and within the gastrointestinal tract. The highest incorporation of deuterium was obtained in homogenates of kidney, lung, and colon, whereas in brain, which contains very low ADH activity, no incorporation could be demonstrated. Addition of extra NAD+ (2.4 mM) increased the formation of [2H]5HTOL 2.6-fold in liver homogenates, but only 1.2-fold in kidney homogenates. 4-Methylpyrazole, a potent inhibitor of class I ADH, inhibited the 5HIAL reduction in homogenates of lung, kidney, jejunum, ileum, and colon, and caused a marked drop in 5HTOL oxidation in all tissues except stomach and spleen. These results demonstrate that in the rat a metabolic interaction between ethanol and serotonin via the ADH pathway may take place in several tissues besides the liver, which is the main tissue for ethanol detoxification.

The Alcohol Use Disorders Identification Test (AUDIT) and carbohydrate-deficient transferrin (CDT) in a routine workplace health examination

BACKGROUND

Only a few studies on workplaces have examined the Alcohol Use Disorders Identification Test (AUDIT) or carbohydrate-deficient transferrin (CDT) as screening instruments for the early identification of elevated and risky levels of alcohol consumption. The purpose of this study was to compare the performances of AUDIT, CDT, and gamma-glutamyltransferase (GGT) in a routine health examination (alcohol screening) in the workplace.

METHODS

The study, carried out over 16 months in a large workplace in the transport sector, was part of an on-going controlled study. Employees who came to the company health service for a routine health examination were offered the opportunity to undergo an alcohol screening and check their alcohol habits.

RESULTS

Of the 570 subjects who participated, 105 (18.4%) screened positive according to AUDIT, CDT, or both. Only 7.6% of the persons who screened positive did so according to both instruments. If GGT had been included as a screening instrument, the proportion of positive results would have increased to 22.0%. If we had only used AUDIT in the screening process, the proportion of positives would have fallen by nearly half.

CONCLUSIONS

The present findings suggest that AUDIT and CDT are complementary instruments for alcohol screening in a routine workplace health examination, and each has value for identifying a different segment of the risky drinking population.

Time course and reproducibility of urinary excretion profiles of ethanol, methanol, and the ratio of serotonin metabolites after intravenous infusion of ethanol

BACKGROUND

The aim of this study was to determine the time course and reproducibility of urinary excretion profiles of ethanol, methanol, and ratio of serotonin metabolites, 5-hydroxytryptophol (5HTOL) to 5-hydroxyindoleacetic acid (5HIAA), under strictly controlled conditions.

METHODS

Nine healthy volunteers (6 women and 3 men) received 0.40 g of ethanol/kg of body weight on two occasions by constant rate intravenous infusion 30 min. Urine was voided before administration of ethanol and thereafter every 60 min for a total of 8 hr. Concentrations of ethanol and methanol in urine were determined by headspace gas chromatography, and the serotonin metabolites 5HTOL and 5HIAA were measured by gas chromatography-mass spectrometry and high-performance liquid chromatography, respectively.

RESULTS

The peak concentration of ethanol in urine occurred at 30 or 60 min after the infusion ended. The peak concentration of methanol and the 5HTOL/5HIAA ratio developed more gradually, reaching a plateau at 213 to 220 min and 200 to 220 min postinfusion, respectively. The concentration-time profiles of ethanol and the 5HTOL/5HIAA ratio varied more between subjects than within subjects (p < 0.001), whereas the inter- and intraindividual variation in the pharmacokinetics of methanol were not significantly different (p > 0.05). The concentration of methanol and the 5HTOL/5HIAA ratio remained above the endogenous levels at 8-hr postinfusion despite the fact that urinary ethanol was no longer measurable (<0.01 g/liter) after 5 to 6 hr.

CONCLUSIONS

Measuring the concentrations of methanol and the ratio of serotonin metabolites (5HTOL/5HIAA) in urine is a more sensitive way to monitor recent drinking, compared with analysis of ethanol in body fluids. Moreover, the concentration-time profiles of methanol and the 5HTOL/5HIAA ratio showed a good test-retest stability. The present intravenous infusion experiment confirms previous work on these markers when ethanol was given perorally. The urinary methanol and the 5HTOL/5HIAA ratio have applications in forensic and clinical medicine as indicators of acute alcohol consumption.

Storage of specimens at 4 degrees C or addition of sodium fluoride (1%) prevents formation of ethanol in urine inoculated with Candida albicans

The microbial synthesis of ethanol was investigated in urine specimens containing 0.5% or 1.0% (w/v) glucose and inoculated with the yeast Candida albicans (100 cfu/mL). Aliquots (10 mL) of urine were dispensed into plastic tubes containing enough sodium fluoride to give final concentrations of 0.1%, 0.25%, 0.5%, 0.75%, 1%, and 2% (w/v), and C. albicans was added. The tubes were tightly stoppered and allowed to stand either at room temperature (22 degrees C) or in a refrigerator (4 degrees C) for up to 34 days before concentrations of ethanol were determined by headspace gas chromatography. Urine samples stored at 22 degrees C without sodium fluoride produced 0.25 g/L ethanol after two days, and the concentration increased to 2.10 g/L and 4.50 g/L after eight days for specimens containing 0.5% (w/v) and 1% (w/v) glucose, respectively. The ratio of the serotonin metabolites 5-hydroxytryptophol/5-hydroxyindoleacetic acid (5HTOL/5HIAA) in urine remained within the reference range (< 15 pmol/nmol) despite high concentrations of ethanol being produced. Urine samples kept at 4 degrees C did not produce any ethanol (< 0.01 g/L) even without sodium fluoride present as a preservative. The production of ethanol by C. albicans was stopped completely by adding 1% or 2% (w/v) sodium fluoride but not by concentrations of 0.75% (w/v) or less. The microbial synthesis of ethanol in urine samples initially stored at room temperature without sodium fluoride was slowed down considerably by moving them into a refrigerator at 4 degrees C. In conclusion, the production of ethanol in urine by C. albicans can be prevented by storage of samples in a refrigerator at 4 degrees C or by adding sodium fluoride > or = 1% (w/v). Measuring the ratio of 5HTOL/5HIAA can help to distinguish postsampling production of ethanol from metabolism and excretion processes.