Is Carbohydrate-Deficient Transferrin a Specific Marker for Alcohol Abuse? A Study in Patients with Chronic Viral Hepatitis

Carbohydrate-Deficient Transferrin (CDT) as a Biomarker of Alcohol Abuse: A Retrospective Study of the Italian Drinking Trend among Drivers from 2016 to 2022

Alcohol abuse is still one of the leading causes of death worldwide. Early diagnosis of alcohol abuse enables preventive intervention on the effects and risks associated with its consumption. Carbohydrate-deficient transferrin (CDT) is one of the most reliable biomarkers of chronic alcohol misuse. We retrospectively studied a population of 12,624 subjects who had their driving license suspended for driving under the influence of alcohol or drugs from 2016 to 2022. The analytical determination of CDT was performed following a certified high-performance liquid chromatography (HPLC) method. Data were split by year, age and gender. The majority of subjects with positive %CDT were male, although the trend of positivity was similar between males and females. A steady increase in both the number of tests performed and the number of positives was observed over the years. Patients aged 41-50 years had the highest prevalence, followed by 51-60, 31-40 and 18-30 years. CDT continues to be a steady marker for diagnosis of alcohol abuse in the majority of cases. Data emerging from our study are in line with the increasing national trends on traffic accidents, injuries and deaths related to alcohol and drug DUI (driving under the influence), requiring the implementation of preventive measures to limit this ever-growing phenomenon.

N-Latex CDT results in liver diseases

AIMS

The aim of this study was to test whether liver diseases of alcoholic and non-alcoholic origin cause false-positive carbohydrate-deficient transferrin (CDT) results when the particle-enhanced immunonephelometry for CDT assays is used and to assess the effect of liver disease severity on N-Latex CDT results.

METHODS

Blood was sampled from 245 newly admitted patients suffering from liver diseases: alcoholic and non-alcoholic cirrhosis (AC), chronic viral (B and C) and non-viral hepatitis, toxic and autoimmune hepatitis (AIH), hepatocellular carcinoma and primary biliary cirrhosis (PBC). CDT was determined by particle-enhanced imunononephelometry using the N-Latex CDT test.

RESULTS

There were significant differences in %CDT levels between liver diseases of various etiologies. The %CDT level in AC was higher than that in chronic hepatitis (non-viral and viral C). In turn, the %CDT level in chronic hepatitis C was lower than that in toxic hepatitis. The frequency of false-positive %CDT results in liver diseases of non-alcoholic origin was 13/146, and was highest in AIH (4/14). There were no CDT-positive results in PBC and chronic hepatitis B. The frequency of CDT-positive results in alcoholic liver diseases was 24/59 in cirrhosis and 10/34 in hepatitis. Serum levels of %CDT in cirrhotic patients are correlated with the severity of the disease assessed by the Child-Pugh score.

CONCLUSION

We concluded that the liver diseases affect the relative but not absolute values of CDT when using the assay with the monoclonal antibodies directed against CDT. The CDT results from N-Latex CDT test reflect the severity of liver dysfunction.

Plasma N-glycan profiling by mass spectrometry for congenital disorders of glycosylation type II

BACKGROUND

Determination of the genetic defect in patients with a congenital disorder of glycosylation (CDG) is challenging because of the wide clinical presentation, the large number of gene products involved, and the occurrence of secondary causes of underglycosylation. Transferrin isoelectric focusing has been the method of choice for CDG screening; however, improved methods are required for the molecular diagnosis of patients with CDG type II.

METHODS

Plasma samples with a typical transferrin isofocusing profile were analyzed. N-glycans were released from these samples by PNGase F [peptide-N4-(acetyl-β-glucosaminyl)-asparagine amidase] digestion, permethylated and purified, and measured on a MALDI linear ion trap mass spectrometer. A set of 38 glycans was used for quantitative comparison and to establish reference intervals for such glycan features as the number of antennae, the level of truncation, and fucosylation. Plasma N-glycans from control individuals, patients with known CDG type II defects, and patients with a secondary cause of underglycosylation were analyzed.

RESULTS

CDGs due to mannosyl (α-1,6-)-glycoprotein β-1,2-N-acetylglucosaminyltransferase (MGAT2), β-1,4-galactosyltransferase 1 (B4GALT1), and SLC35C1 (a GDP-fucose transporter) defects could be diagnosed directly from the N-glycan profile. CDGs due to defects in proteins involved in Golgi trafficking, such as subunit 7 of the conserved oligomeric Golgi complex (COG7) and subunit V0 a2 of the lysosomal H(+)-transporting ATPase (ATP6V0A2) caused a loss of triantennary N-glycans and an increase of truncated structures. Secondary causes with liver involvement were characterized by increased fucosylation, whereas the presence of plasma sialidase produced isolated undersialylation.

CONCLUSIONS

MALDI ion trap analysis of plasma N-glycans documents features that discriminate between primary and secondary causes of underglycosylation and should be applied as the first step in the diagnostic track of all patients with an unsolved CDG type II.

Combined effects of alcohol and hepatitis C: a secondary analysis of alcohol use biomarkers and high-risk behaviors from two medication trials for alcohol dependence

OBJECTIVES

The goal of this secondary analysis was to examine the combined effects of HCV infection and recent alcohol use on baseline biologic markers of alcohol consumption in two outpatient medication trials for alcohol dependence. In addition, the relationship between Hepatitis C virus (HCV) infection and behavioral risk factors for HCV infection in these clinical populations were examined.

METHODS

Data (n=345) from two randomized, placebo-controlled trials of naltrexone and psychosocial treatment for alcohol dependence (Study I, n=212) and comorbid alcohol and cocaine dependence (Study II, n=133) were used to examine baseline measures of HCV risk behaviors (injection drug use, needle sharing), and biomarkers of alcohol use (AST, ALT, GGT and CDT) were compared by HCV serostatus first within each study and then across studies.

RESULTS

Although groups had differing sociodemographic profiles (as indicated by race, marital status, level of education) subjects in Study I exhibited no statistically significant differences from the Study II cohort in HCV prevalence (12.7 vs. 20.0%, p=0.07), lifetime history of injection drug use (13.8 vs. 22.0%, p=0.74), lifetime history of needle sharing (9.1 vs. 18.0%, p=0.62). As such, the data from both studies were analyzed together. Regardless of drinking status, HCV infection was significantly associated with an upward shift in the baseline level of ALT, AST, and GGT (p<0.006 for all measures) and a downward shift in baseline CDT (p=0.002). When using standard laboratory cutoff values to determine clinically significant elevations, HCV seropositivity was significantly associated with elevations in ALT, AST, GGT (p<0.001), and with decreases in CDT (p=.002).

CONCLUSIONS

These data emphasize the importance of evaluating HCV infection and HCV risk behaviors at intake in medication trials for alcohol dependence and also raise questions regarding the use of cutoff scores for ALT, AST, GGT and CDT levels as biologic markers of alcohol use in subjects when HCV status is unknown.

The diagnostic value of combining carbohydrate-deficient transferrin, fibrosis, and steatosis biomarkers for the prediction of excessive alcohol consumption

BACKGROUND AND AIM

The validity of biomarkers of excessive alcohol drinking (EAD) (30 g/day or more), such as carbohydrate-deficient transferrin (CDT%), is confounded by liver disease severity. The aim was to improve the accuracy of the percentage of CDT by taking into account the presence of fibrosis and steatosis, estimated using biomarkers FibroTest and SteatoTest.

METHODS

Three hundred and twenty consecutive patients, 97 with alcoholic liver disease (ALD), and 223 non-ALD, were included. In ALD, 58% had advanced fibrosis and 58% had steatosis; in non-ALD, 25% had advanced fibrosis and 25% had steatosis.

RESULTS

The mean percentage of CDT was lower in ALD with advanced fibrosis [2.4 (SE=0.2)] versus without [4.1 (0.3) P<0.0001], and lower in ALD with steatosis versus without (2.4 vs. 3.9; P=0.0007). Among non-ALD, there was no difference in the percentage of CDT according to fibrosis or steatosis. gamma-glutamyl-transpeptidase was higher in patients with advanced fibrosis or with steatosis both in ALD and non-ALD. Aspartate aminotransferase/alanine aminotransferase (AST/ALT) was higher in ALD patients with fibrosis versus without (2.5 vs. 1.3 P<0.0001) but not in non-ALD (1.01 vs. 0.98). AST/ALT was higher in ALD patients with steatosis versus without (2.2 vs. 1.6 P=0.04) and the inverse was observed in non-ALD (0.6 vs. 1.1 P<0.0001). In the entire population the percentage of CDT, gamma-glutamyl-transpeptidase, AST/ALT was associated with EAD, the area under the receiver operating characteristic curve =0.89 (95% CI: 0.84-0.93), 0.93 (0.89-0.93) and 0.77 (0.71-0.82). An algorithm combining the percentage of CDT, FibroTest and SteatoTest permitted to obtain area under the receiver operating characteristic curve=0.92 versus 0.88 for the percentage of CDT (P=0.004) with 87.4% of patients classified correctly.

CONCLUSION

Biomarkers of EAD are confounded by fibrosis and steatosis. Accuracy of the percentage of CDT is significantly increased when combined with biomarkers of fibrosis and steatosis.

Screening Using Serum Percentage of Carbohydrate-Deficient Transferrin for Congenital Disorders of Glycosylation in Children with Suspected Metabolic Disease

Background: Diagnoses of congenital disorders of glycosylation (CDG) are based on clinical suspicion and analysis of transferrin (Tf) isoforms. Here we present our experience of CDG screening in children with a suspected metabolic disease by determination of serum percentage of carbohydrate-deficient transferrin (%CDT) in tandem with isoelectric focusing (IEF) analysis of Tf and α1-antitrypsin (α1-AT).

Methods: We performed approximately 8000 serum %CDT determinations using %CDT turbidimetric immunoassay (TIA). In selected samples, IEF analysis of Tf and α1-AT was carried out on an agarose gel (pH 4–8) using an electrophoresis unit. The isoforms were detected by Western blotting and visualized by color development. We performed neuraminidase digestion of serum to detect polymorphic variants of Tf.

Results: We established a cutoff value for serum %CDT of 2.5% in our pediatric population. Sixty-five patients showed consistently high values of serum %CDT. In accordance with Tf and α1-AT IEF profiles, enzyme assays, and mutation analysis, we made the following diagnoses: 23 CDG-Ia, 1 CDG-Ib, and 1 conserved oligomeric Golgi 1 (COG-1) deficiency. In addition, we identified 13 CDG-Ix non Ia, non-Ib; 3 CDG-Ix; and 9 CDG-IIx cases, albeit requiring further characterization; 9 patients with a secondary cause of hypoglycosylation and 6 with a polymorphic Tf variant were also detected.

Conclusion: The combined use of CDT immunoassay with IEF of Tf and α1-AT is a useful 1st-line screening tool for identifying CDG patients with an N-glycosylation defect. Additional molecular investigations must of course be carried out to determine the specific genetic disease.

Relationship of smoking and fibrosis in patients with chronic hepatitis C

BACKGROUND & AIMS

Preliminary studies have suggested that in patients with chronic hepatitis C (CHC), cigarette smoking increases the risk for developing liver fibrosis. Hypoxia caused by smoking may induce expression of the cytokines' vascular endothelial growth factor (VEGF) and VEGF-D and their corresponding soluble tyrosine kinase receptors fms-like tyrosine kinase receptor (s-Flt) and kinase insert domain receptor (s-KDR). These cytokine levels are increased in animals with cirrhosis and in human beings with CHC. We studied whether the concentrations of VEGF, VEGF-D, s-Flt, and s-KDR were increased in CHC smokers with and without hepatic fibrosis.

METHODS

A total of 170 CHC patients were identified retrospectively from a single center's database. In 59 patients, serum levels of VEGF, VEGF-D, s-Flt, and s-KDR were measured using an enzyme-linked immunosorbent assay.

RESULTS

All 170 patients were hepatitis C virus RNA positive, 117 (69%) were men, 43 (25%) were smokers, and their mean (+/-SD) age was 47 (+/-6) years. Overall, 21% of smokers had Metavir fibrosis scores of 3 and 4 compared with 14% of nonsmokers (P < .01). In an age-weighted multivariate model using step-wise logistic regression, smoking, infection with hepatitis C virus genotype 1, male sex, and increased VEGF-D concentration all were significant independent predictors of more severe liver fibrosis (P < .05 for all observations).

CONCLUSIONS

These data suggest that CHC patients who smoke may have more hepatic fibrosis. The data also suggest that increased VEGF and VEGF-D concentrations are associated with smoking and may be involved in the molecular mechanisms of fibrogenesis.

A review of genetic, biological, pharmacological, and clinical factors that affect carbohydrate-deficient transferrin levels

BACKGROUND

Carbohydrate-deficient transferrin (CDT) is an alcohol biomarker recently approved by the U.S. Food and Drug Administration. This test is increasingly being used to detect and monitor alcohol use in a variety of health care, legal, and industrial settings. The goal of this study is to review the genetic, biological, pharmacological, and clinical factors that may affect CDT levels.

METHODS

A review of the literature identified 95 research articles that met the authors' criteria and reported potential interactions of a variety of factors on percent and total CDT levels. The review established 12 categories of variables that may affect CDT levels. These categories include (1) alcohol use, (2) genetic factors, (3) race, (4) gender, (5) age, (6) liver disease, (7) iron levels, (8) tobacco use, (9) medication such as estrogen and anticonvulsants, (10) metabolic factors such as body mass index and total body water, (11) chronic medical conditions such as rheumatoid arthritis, and (12) surgical patients.

RESULTS

There is evidence that %CDT levels are affected by alcohol use, end-stage liver disease, and genetic variants. In addition to these three factors, total CDT levels (CDTect) are also affected by factors that raise transferrin levels such as iron deficiency, chronic illnesses, and menopausal status. Other potential factors such as tobacco and age appear to be confounded by alcohol use. The roles of female gender, low body mass index, chronic inflammatory diseases, and medication on CDT levels require further study. False negatives are associated with female gender, episodic lower level alcohol use, and acute trauma with blood loss.

CONCLUSIONS

This review suggests that a number of factors are associated with false-positive CDTect and %CDT levels. CDT offers great promise to assist physicians in the care of patients to detect and monitor heavy alcohol use.

The analysis of carbohydrate-deficient transferrin, marker of chronic alcoholism, using capillary electrophoresis

Carbohydrate-deficient transferrin (CDT) is currently considered to be the best available marker for the diagnosis of chronic alcoholism. A large variety of methods have been developed, demonstrating the need for standardisation. Commercially available anion-exchange chromatographic-based assays are easy to use and require no specialised, expensive instruments. However, these methods cannot identify genetic transferrin variants or the carbohydrate-deficient glycoprotein syndrome. In 1989, a capillary isoelectric focusing method was developed for quantitative measurement of CDT. Despite the optimal resolution, this method is not easily applied in a clinical routine environment due to the complexity of analysis. Capillary electrophoresis in a polymer network using coated capillaries allowed full resolution of the sialoforms of human transferrin. The drawbacks due to an expensive and time-consuming sample preparation were eliminated when a method in neat serum was developed. Capillary zone electrophoresis allowed full resolution of the transferrin isoforms with a high analytical performance in a short analysis time thanks to a strong electroosmotic flow. Genetic transferrin variants were easily detected, avoiding false-positive results. Also, using capillary zone electrophoresis, it was shown that CDT is a suitable marker of chronic alcohol abuse detection in transferrin CD (common/cathodal) variants.

Biochemical markers of alcohol use in pregnant women

OBJECTIVES

To describe the serious health consequences of alcohol (ethanol) use, especially as they relate to pregnancy and the development of fetal alcohol syndrome (FAS) and fetal alcohol effects (FAE). The classic markers of alcohol exposure, including blood/breath alcohol, gamma-glutamyl transferase (gammaGT), mean corpuscular volume (MCV), hemoglobin-associated acetaldehyde (HAA) and carbohydrate deficient transferrin (CDT), are valuable and their methods of analysis are reviewed.

CONCLUSIONS

Since both FAS and FAE represent two of the leading preventable causes of mental retardation and birth defects, identification of alcohol use early in pregnancy is important to avoid adverse fetal outcomes. Unfortunately, the diagnosis of FAS and FAE is usually made after birth, when alcohol damage has become irreversible and permanent. The clinical laboratory can help prevent this damage and make a valuable contribution in assessing prenatal alcohol use. The clinical utility of blood/breath alcohol, gammaGT, MCV, HAA and CDT in alcohol use identification, especially in pregnancy, is substantial. Although none of the markers singularly has adequate sensitivity and specificity for screening, their diagnostic utility increases when measured as a panel. This is especially true in detecting alcohol use in pregnancy where the presence of several positive markers was correlated with the presence of alcohol-related fetal effects.

Plasma sialic-acid index of apolipoprotein J (SIJ): a new alcohol intake marker

Although plasma carbohydrate-deficient transferrin (CDT) is considered a viable biochemical marker for chronic alcohol consumption, it is valid only when an individual's daily alcohol consumption exceeds 60 g. In addition, it is less sensitive in women drinkers than in men drinkers. We have established that chronic alcohol consumption impairs the hepatic sialylation of a number of glycoproteins by specifically down-regulating Gal-beta-1,4GlcNAc alpha2,6-sialyltransferase mRNA. Significantly, we found that chronic ethanol consumption markedly inhibits hepatic sialylation of apolipoprotein J (Apo J), a 70-kDa N-glycosylated protein of plasma HDL. Because the sialic-acid index of Apo J (SIJ; moles of sialic acid per mole of Apo J protein) is approximately seven times more than that for transferrin (28 vs. 4), we have evaluated whether plasma SIJ would be an even more sensitive marker for chronic ethanol consumption than CDT in both rats and human subjects. The method involves immunoaffinity purification of plasma HDL-Apo J, followed by its sialic acid determination. We have found that chronic ethanol feeding resulted in loss of sialic acid residues of plasma HDL-Apo J in rats. This loss of sialic acid was positively correlated with both amount and duration of ethanol treatment. In human subjects, an intake of about 60 g of alcohol for 30 days led to almost 50% (P <.01) depletion of sialic acid from plasma HDL-Apo J. Further, we established that there was a positive correlation of alteration in SIJ with alcohol consumption, detoxification, abstinence, and relapse in human alcohol-dependent patients (sensitivity, 90%-92%). In addition, plasma SIJ was decreased by 50%-57% (P <.01) in both male and female alcohol-dependent subjects. We suggest that plasma SIJ can be used as a viable marker for early detection of chronic alcohol consumption in human beings.

The role of biomarkers in alcoholism medication trials

BACKGROUND

Increasingly, biomarkers are being incorporated into the research design of clinical trials on medications to reduce drinking in alcoholics. To date, however, there has been little analysis of the unique roles that biomarkers can play in such investigations or of the practical and conceptual considerations that surround their best use in this context.

METHODS

Clinical trials of alcoholism medications published between 1985 and the present were abstracted to determine how biomarkers were used and how changes in them related to self-report measures of drinking.

RESULTS

Six uses of biomarkers were identified: determination of subjects to be included or excluded in the trial; description of baseline sample characteristics; primary and secondary outcome assessment; corroboration of self-reports of drinking status; specification of patients likely to respond to the medication; and evaluation of drug safety.

CONCLUSION

Use of biomarkers in such studies appears warranted, particularly as an objective source of information on treatment efficacy that can be considered with patient self-report measures of drinking status. Biomarkers related to liver functioning also can assist in determination of drug safety for medications metabolized by the liver.

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 ∼0.7% and ∼0.2%, respectively. Another transferrin C subtype, where di- and trisialotransferrin partly coeluted (tentatively identified as C2C3), was observed in ∼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 ∼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 ∼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.

Carbohydrate-deficient Transferrin as a Marker of Chronic Alcohol Abuse: A Critical Review of Preanalysis, Analysis, and Interpretation

Background: Carbohydrate-deficient transferrin (CDT) is used for diagnosis of chronic alcohol abuse. Some 200–300 reports on CDT have been published in impact factor-listed journals. The aims of this review were to condense the current knowledge and to resolve remaining issues on CDT.

Approach: The literature (1976–2000) was searched using MEDLINE and Knowledge Server with “alcohol and CDT” as the search items. The data were reviewed systematically, checked for redundancy, and organized in sequence based on the steps involved in CDT analysis.

Content: The review is divided into sections based on microheterogeneity of human serum transferrin (Tf), definition of CDT, structure of human serum CDT, pathomechanisms of ethanol-induced CDT increase, preanalysis, analysis, and medical interpretation (postanalysis). Test-specific cutoff values for serum CDT and causes of false positives and negatives for chronic alcohol abuse are discussed and summarized.

Summary: Asialo- and disialo-Fe2-Tf, which lack one or two complete N-glycans, and monosialo-Fe2-Tf (structure remains unclear) are collectively referred to as CDT. Diminished mRNA concentration and glycoprotein glycosyltransferase activities involved in Tf N-glycan synthesis and increased sialidase activity most likely account for alcohol-induced increases in CDT. Knowledge about in vivo and in vitro effects on serum CDT is poor. Reliable CDT and non-CDT fractionation is needed for CDT measurement. Analysis methods with different analytical specificities and recoveries decreased the comparability of values and statistical parameters of the diagnostic efficiency of CDT. CDT is the most specific marker of chronic alcohol abuse to date. Efforts should concentrate on the pathomechanisms (in vivo), preanalysis, and standardization of CDT analysis.

Carbohydrate-deficient transferrin in the assessment of harmful alcohol consumption: diagnostic performance and clinical significance

The last decade saw the emergence of carbohydrate-deficient transferrin (CDT) as the most promising marker for the diagnosis of alcohol abuse. Daily alcohol consumption of four beers, four glasses of wine or three standard drinks causes increased concentrations of CDT in serum. CDT is serum transferrin with a reduced content of oligosaccharides due to the detrimental effects of alcohol metabolism on the glycosylation pathway of hepatocytes and/or the increased activity of circulating glycosidases in serum. Most current CDT procedures entail separation of normal transferrin from CDT in a charged matrix-like isoelectric focusing and ion exchange chromatography, followed by detection/quantitation of CDT by a myriad of immunoassays: immunoblotting, radioimmunoassay, enzyme immunoassay and nephelometry. New CDT procedures present the advantages of improved performance, inexpensive automation and CDT results expressed as a percentage of total serum transferrin. CDT's major asset is its high specificity in well-defined populations i.e. individuals ingesting 60 g alcohol daily for at least a week.The sensitivity rates, which vary between 22% and 81%, depend on the amount of alcohol ingested, time of sample collection after the cessation of drinking, age, gender and the cut-off point chosen for analysis of tests' results. Regarding clinical applications, best outcome is achieved when the test is used to confirm a suspicion of alcohol abuse and when monitoring abstinence and relapses.The low prevalence of alcohol abuse in the general population challenges its use as a screening test.With the advent of inexpensive automation and the constant emergence of innovative, improved tests, we are seeing the rise of a new era in alcohol abuse diagnosis as affordability and education allows widespread use of CDT in a variety of settings.

Alcohol problems in a general hospital

Alcohol is a ubiquitous drug which is responsible for a substantial amount of ill health and approximately 20% of patients in a general hospital will have alcohol-related problems, although only 4% will be admitted with alcohol-caused conditions. Eight per cent of patients, however, can be expected to have sufficient neuroadaptation to be at risk of withdrawal. This level of prevalence of alcoholism in general hospital patients requires that hospitals must become expert at providing good quality care for alcohol-related problems in all areas including obstetrics, but particularly in the management of intoxication, withdrawal and the various alcohol-related diseases. This paper provides some suggested benchmarks for acceptable standards of care for alcohol problems in the acute hospital.

Proteome in perspective

This review describes briefly proteome science. It explains why proteome science or proteomics emerged only recently and why a shift from genomics to proteomics is occurring. This review further illustrates that proteomics can unravel new domains in nature's complexity. Finally, it demonstrates that proteomics is offering new tools for the study of complex biological or medical problems.

Intra- and interindividual variability of carbohydrate-deficient transferrin, γ-glutamyltransferase, and mean corpuscular volume in teetotalers

Blood samples for determination of the biochemical alcohol markers carbohydrate-deficient transferrin (CDT) in serum, γ-glutamyltransferase (GGT) in serum, and erythrocyte mean corpuscular volume (MCV) were collected once every 1–2 weeks over ∼5 months from 10 female and 4 male teetotalers. Mean values for serum CDT (using the CDTectTM assay) ranged from 9.9 to 29.4 units/L (median, 14.2 units/L), and the highest results were obtained in the women. The mean values for serum GGT ranged from 0.15 to 0.49 μkat/L (median, 0.30 μkat/L, or 18 U/L) except for one woman with a very high mean of 3.07 μkat/L. For MCV, the mean values ranged from 79.5 to 91.5 fL. Two women showed several CDT results above the upper reference limit (mean values, 27.6 and 29.4 units/L, respectively); however, their GGT and MCV values fell within the reference intervals. One of these women exhibited an increased total transferrin concentration (mean value, 5.38 g/L), which was possibly related to the use of oral contraceptives and/or a low serum iron concentration. When the CDTect value was expressed relative to total transferrin, a ratio within the reference interval was observed for this woman but not for the other woman with increased CDTect values. The present study demonstrates a considerable variation between individuals in CDT, GGT, and MCV without drinking any alcohol. The results also show that these baseline values are fairly constant over time within the same individual.