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.

Urine 5-hydroxyindoleacetic acid in Cavalier King Charles spaniels with preclinical myxomatous mitral valve disease.

Higher concentrations of circulating serotonin have been reported in Cavalier King Charles spaniels (CKCS) compared to other dog breeds. The CKCS is also a breed highly predisposed to myxomatous mitral valve disease (MMVD). The aim of this study was to determine urine concentrations of 5-hydroxyindoleacetic acid (5-HIAA), the major metabolite and excretion product of serotonin, in a population of CKCS with preclinical MMVD, and to evaluate whether urine 5-HIAA concentrations were associated with MMVD severity, dog characteristics, setting for urine sampling, platelet count, and serotonin concentration in serum and platelet-poor plasma (PPP). The study population consisted of 40 privately-owned CKCS (23 females; 17 males) with and without preclinical MMVD as follows: American College of Veterinary Internal Medicine (ACVIM) group A (n = 11), ACVIM group B1 (n = 21) and ACVIM group B2 (n = 8). Urine 5-HIAA concentrations were not significantly associated with preclinical MMVD disease, platelet count or circulating concentrations of serotonin (in serum and PPP; P > 0.05). Females had higher 5-HIAA concentrations than males in morning urine collected at home (females, 3.1 [2.9-3.7] µmol/mmol creatinine [median and quartiles]; males, 1.7 [1.2-2.2] µmol/mmol creatinine; P = 0.0002) and urine collected at the clinic (females, 3.5 [3.1-3.9] µmol/mmol creatinine; males, 1.6 [1.3-2.1] µmol/mmol creatinine; P < 0.0001). Five-HIAA concentrations in urine collected at home and at the clinic were significantly associated (P = 0.0004; r = 0.73), and higher concentrations were found in urine collected at the clinic (P = 0.013). Urine 5-HIAA concentration was influenced by sex and setting of urine sampling. Urine 5-HIAA concentration was not associated with MMVD severity or circulating concentrations of serotonin in CKCS with preclinical disease.

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.

MT-45, a new psychoactive substance associated with hearing loss and unconsciousness.

BACKGROUND: MT-45 (1-cyclohexyl-4-(1,2-diphenylethyl)piperazine) is an opioid analgesic drug candidate developed in the 1970s that has recently been introduced as a new psychoactive substance (NPS) on the "recreational" drug market. We describe a case series of non-fatal intoxications associated with MT-45 within the Swedish STRIDA project. STUDY DESIGN: Observational case series of consecutive patients with admitted or suspected intake of NPS presenting to hospitals in Sweden from November 2013 to February 2014. PATIENTS AND METHODS: Blood and urine samples were collected from intoxicated patients presenting to emergency departments and intensive care units over the country. NPS analysis was performed by an LC-MS/MS multi-component method. Clinical data were collected when caregivers consulted the Poisons Information Centre and also retrieved from medical records. CASE SERIES. Among nine intoxications where MT-45 was detected in the biological samples, four cases were indicated to only involve MT-45, while one or several psychoactive substances were found along with MT-45 in the others. All patients were men aged 17-32 years and they commonly presented with opioid-like adverse symptoms, such as unconsciousness and respiratory depression. Naloxone appeared to have utility in the treatment of MT-45 intoxication in several cases. Three patients complained of bilateral hearing loss that in one case persisted after two weeks. CONCLUSION: MT-45 should be added to the growing list of harmful NPS causing life-threatening poisonings, and rapid actions taken to make it a controlled substance.

Intoxications of the new psychoactive substance 5-(2-aminopropyl)indole (5-IT): a case series from the Swedish STRIDA project.

CONTEXT: 5-(2-aminopropyl)indole (5-IT) is a new psychoactive substance (NPS; "legal high" or "research chemical") structurally related to indoleamines and substituted phenethylamines and implicated in several fatalities. We describe the clinical characteristics and results of laboratory investigations of 14 analytically confirmed nonfatal cases of 5-IT intoxication within the Swedish STRIDA project. STUDY DESIGN: Observational case series of consecutive patients with admitted or suspected intake of NPS presenting to hospitals in Sweden in 2012. PATIENTS AND METHODS: Blood and/or urine samples were collected from intoxicated patients presenting to emergency departments and intensive care units over the country. Analysis of NPS was performed using an LC-MS/MS multi-component method. Clinical data were collected when caregivers consulted the Poisons Information Centre and also retrieved from medical records. The severity of poisoning was graded retrospectively using the Poisoning Severity Score (PSS). RESULTS: Eleven male and three female patients (age: 21-53 years, median: 27) tested positive for 5-IT in 2012, all cases appearing in April-July. The 5-IT concentration in serum ranged between 0.015 and 0.59 µg/mL (median: 0.22; n = 8) and in urine between 0.005 and 24.7 µg/mL (median: 5.95; n = 12). Five intoxications were indicated to be caused by 5-IT alone, whereas additional psychoactive substances were detected in the other nine cases. Six (43%) of fourteen cases were graded as severe (PSS 3), five (36%) as moderate (PSS 2), and three (21%) as minor (PSS 1) poisonings. In the severe cases, agitation, hallucinations, dilated pupils without light reaction, tachycardia, hypertension, hyperthermia, myoclonus, muscle rigidity, arrhythmias, seizures, rhabdomyolysis, and/or renal failure were noted. CONCLUSIONS: The results demonstrated that severe clinical toxicity was commonly present in patients with analytically confirmed 5-IT exposure. The clinical features are consistent with a sympathomimetic toxidrome, and some patients also displayed symptoms associated with serotonin toxicity.

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.

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.

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.

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.

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.

[CDT a valuable marker of overconsumption of alcohol. Guidelines for its use in connection with automobile driver examination]. / CDT värdefull markör för överkonsumtion av alkohol. Riktlinjer för dess användning vid körkortsprövning.

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.

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.