Pregnancy and variations of carbohydrate-deficient transferrin levels measured by the candidate reference HPLC method

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.

Defining trimester-specific reference intervals for carbohydrate deficient transferrin in pregnant women

OBJECTIVES

Extensive consumption of alcohol during pregnancy can lead to severe complications for the unborn child. Carbohydrate-deficient transferrin (CDT) levels in serum have become a common biomarker for excessive alcohol intake. However, during pregnancy CDT levels can rise to levels above commonly used cut-off values, for reasons unrelated to alcohol intake. The aim of this study is to investigate the changes in CDT values during pregnancy and to determine accurate, trimester dependent reference intervals.

METHODS

439 serum samples of 147 healthy pregnant women were obtained for trimester 1, 2, 3, and post-partum and were analysed by high-performance liquid chromatography (HPLC) and an N-Latex immunonephelometric assay. New trimester-specific reference intervals were established.

RESULTS

This study demonstrates there is a trimester-dependent increase of %CDT, as up to 39.4% of the population exceeded the previously established upper reference limit of 1.7%. In our study the estimated upper reference limit for %DST/%CDT were 1.55%, 1.96%, 2.05% and 1.35% for trimester 1, 2, 3 and post-partum for the HPLC-method and 2.02%, 2.19%, 2.19% and 1.96% for the N-Latex immunoassay.

CONCLUSIONS

We demonstrate that CDT levels rise during pregnancy. The magnitude of the increase is method-dependent and needs to be taken into account. We have established method- and trimester-specific reference intervals to prevent false-positive results in alcohol abuse screening tests during pregnancy.

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.

An Integrative Screening Tool of Alcohol Exposure During Early Pregnancy: Combining of the CDT Biomarker with Green Page Questionnaire

AIMS

In current clinical practice, prenatal alcohol exposure is usually assessed by interviewing the pregnant woman by applying questionnaires. An alternative method for detecting alcohol use is to measure the biomarker carbohydrate-deficient transferrin (CDT). However, few studies measure CDT during pregnancy. This study examines the utility of CDT biomarker in the screening of alcohol exposure during early pregnancy.

METHODS

A cohort of 91, first-trimester pregnant women assigned to a public reference maternity hospital, was screened using the Green Page (GP) questionnaire, an environmental exposure tool. CDT levels and other biomarkers of alcohol use were measured and compared with questionnaire data.

RESULTS

About 70% of the mothers in the study consumed alcohol during early pregnancy and 22% met high-risk criteria for prenatal exposure to alcohol. CDT measurement showed a statistically significant area under the receiver operating characteristic curve with a value of 0.70. For a value of 0.95% of CDT, a specificity of 93% was observed. The most significant predictors of CDT were the number of binge drinking episodes, women's body mass index and European white race.

CONCLUSION

Pregnant women with a CDT value >0.95% would be good candidates for the performance of the GP questionnaire during early pregnancy in order to detect potential high-risk pregnancy due to alcohol exposure.

CDT reference values for monitoring chronic alcohol abuse in pregnancy

INTRODUCTION AND AIM

Carbohydrate Deficient Transferrin (CDT) is one of the most used biomarkers for monitoring alcohol use in pregnancy. However, its effective application in this context is hampered by the demonstrated physiological progressive increase during pregnancy (even in abstinent women) of CDT values, which in the third trimester can reach values close or exceeding the cut-offs usually adopted in clinical and forensic diagnostics. The present work was aimed at the re-assessment of CDT reference values in pregnancy.

MATERIALS AND METHODS

The CDT analysis was performed by a validated HPLC-UV Vis method on 284 serum samples of women with a physiological pregnancy and on 370 sera of non-pregnant woman from the general population (control group). All the samples were tested also for GGT for excluding alcohol abuse. The statistical analysis was performed using the MedCalc® Statistical Software.

RESULTS

The re-definition of the specific reference concentrations was carried out according to the Horn and Pesce Robust Method. The resulting CDT upper reference values were 1.45%, 2.01% and 2.05% in the first, second, and third trimester, respectively.

CONCLUSIONS

In order to prevent the development of maternal and fetal prenatal alcohol exposure complications, the use of alcohol biomarkers, including CDT, has been proposed. However, this biomarker, in the monitoring of alcohol use in pregnancy, has so far been applied adopting the same cut-off used for general population without taking into consideration the progressive physiological increase of its value throughout the pregnancy. In the present study, a specific re-assessment of the CDT reference concentrations of each trimester is reported.

Asialo-transferrin: Biochemical aspects and association with alcohol abuse investigation

Asialo-human transferrin (asialo-hTf) is a glycoform of the human serum protein transferrin characterized by the lack of the sialic acid (SA) terminal unit. It is known that glycosylation micro-heterogeneity and the presence of SA are strongly involved in protein functioning and pathophysiological activities. Some hTf glycoforms are valuable biomarkers for the detection of both genetic defects of glycosylation and/or sialoform distribution changes. The detection of the carbohydrate deficient transferrin (CDT) glycoforms is currently a widely employed method for the diagnosis of chronic alcohol abuse. The physiological significance of asialo-hTf is still unclear, despite its important biological implications. The current knowledge suggests that asialo-hTf may be involved in regulation of iron transport and release at the hepatic level, which, consequently, could strongly be affected by alcohol consumption. For these reasons, a deeper understanding of asialo-hTf structure and its physiological role is required, and an improved method of its analysis would favor the detection of both chronic abuse and other habits of alcohol intake and/or misuse. Thus, suitable analytical methods possessing higher sensitivity and specificity in comparison with the currently available techniques are certainly recommended. The present review summarizes the studies on asialo-hTf structure, roles, and detection techniques mainly in relation to its possible use as a potentially additional useful biomarker of alcohol abuse, and underlines its prospective value as a forensic and diagnostic tool.

Analytical and diagnostic aspects of carbohydrate deficient transferrin (CDT): A critical review over years 2007-2017

The need for investigating alcohol abuse by means of objective tools is worldwide accepted. Among the currently available biomarkers of chronic alcohol abuse, carbohydrate-deficient transferrin (CDT) is one of the most used indicator, mainly because of its high specificity. However, some CDT analytical and interpretation aspects are still under discussion, as witnessed by numerous research papers and reviews. The present article presents a critical review of the literature on CDT appeared in the period from 2007 to 2017 (included). The article is organized in the following sections: (1) introduction, (2) pre-analytical aspects (3) analytical aspects (4) diagnostic aspects (5) concluding remarks. As many as 139 papers appeared in the international literature and retrieved by the search engines PubMed, Web of Science and Scopus are quoted.

[New biomarkers for assesing alcohol consumption]

Alcohol abuse has significant medical, social and socioeconomic consequences. Alcohol biomarkers may serve as a useful tool in identifying individuals with excessive alcohol consumption in medical as well as medico-legal contexts.

Fetal alcohol-spectrum disorders: identifying at-risk mothers

Fetal alcohol-spectrum disorders (FASDs) are a collection of physical and neurobehavioral disabilities caused by prenatal exposure to alcohol. To prevent or mitigate the costly effects of FASD, we must identify mothers at risk for having a child with FASD, so that we may reach them with interventions. Identifying mothers at risk is beneficial at all time points, whether prior to pregnancy, during pregnancy, or following the birth of the child. In this review, three approaches to identifying mothers at risk are explored: using characteristics of the mother and her pregnancy, using laboratory biomarkers, and using self-report assessment of alcohol-consumption risk. At present, all approaches have serious limitations. Research is needed to improve the sensitivity and specificity of biomarkers and screening instruments, and to link them to outcomes as opposed to exposure. Universal self-report screening of all women of childbearing potential should ideally be incorporated into routine obstetric and gynecologic care, followed by brief interventions, including education and personalized feedback for all who consume alcohol, and referral to treatment as indicated. Effective biomarkers or combinations of biomarkers may be used during pregnancy and at birth to determine maternal and fetal alcohol exposure. The combination of self-report and biomarker screening may help identify a greater proportion of women at risk for having a child with FASD, allowing them to access information and treatment, and empowering them to make decisions that benefit their children.

Ethylglucuronide in maternal hair as a biomarker of prenatal alcohol exposure

While direct ethanol metabolites, including ethylglucuronide (EtG), play an important role for the confirmation of prenatal alcohol exposure (PAE), their utility is often limited by their short half-lives in blood and urine. Maternal hair allows for a retrospective measure of PAE for up to several months. This study examined the validity of hair EtG (hEtG) relative to self-reporting and five other biomarkers in 85 pregnant women. Patients were recruited from a UNM prenatal clinic, which provides care to women with substance abuse and addiction disorders. The composite index, which was based on self-reported measures of alcohol use and allowed us to classify subjects into PAE (n = 42) and control (n = 43) groups, was the criterion measure used to estimate the sensitivity and specificity of hEtG. Proximal segments of hair were collected at enrollment (average 22.0 gestational weeks) and analyzed by LC-MS/MS. At the same visit, maternal blood and urine specimens were collected for analysis of GGT, %dCDT, PEth, uEtG, and uEtS. The study population included mostly opioid-dependent (80%) patients, a large proportion of ethnic minorities (75.3% Hispanic/Latina, 8.2% American Indian, 4.7% African-American), and patients with low education (48.2% < high school). The mean maternal age at enrollment was 26.7 ± 4.8 years. Hair EtG demonstrated 19% sensitivity and 86% specificity. The sensitivities of other biomarkers were comparable (5-20%) to hEtG but specificities were higher (98-100%). Hair EtG sensitivity improved when combined with other biomarkers, especially with GGT (32.5%) and PEth (27.5%). In addition, validity of hEtG improved in patients with less frequent shampooing and those who did not use hair dyes/chemical treatments. These data suggest that hEtG alone is not a sufficiently sensitive or specific biomarker to be used separately for the identification of PAE, but might be useful in a battery along with other maternal biomarkers.

Biomolecules and Biomarkers Used in Diagnosis of Alcohol Drinking and in Monitoring Therapeutic Interventions

BACKGROUND

The quantitative, measurable detection of drinking is important for the successful treatment of alcohol misuse in transplantation of patients with alcohol disorders, people living with human immunodeficiency virus that need to adhere to medication, and special occupational hazard offenders, many of whom continually deny drinking. Their initial misconduct usually leads to medical problems associated with drinking, impulsive social behavior, and drunk driving. The accurate identification of alcohol consumption via biochemical tests contributes significantly to the monitoring of drinking behavior.

METHODS

A systematic review of the current methods used to measure biomarkers of alcohol consumption was conducted using PubMed and Google Scholar databases (2010-2015). The names of the tests have been identified. The methods and publications that correlate between the social instruments and the biochemical tests were further investigated. There is a clear need for assays standardization to ensure the use of these biochemical tests as routine biomarkers.

FINDINGS

Alcohol ingestion can be measured using a breath test. Because alcohol is rapidly eliminated from the circulation, the time for detection by this analysis is in the range of hours. Alcohol consumption can alternatively be detected by direct measurement of ethanol concentration in blood or urine. Several markers have been proposed to extend the interval and sensitivities of detection, including ethyl glucuronide and ethyl sulfate in urine, phosphatidylethanol in blood, and ethyl glucuronide and fatty acid ethyl esters in hair, among others. Moreover, there is a need to correlate the indirect biomarker carbohydrate deficient transferrin, which reflects longer lasting consumption of higher amounts of alcohol, with serum γ-glutamyl transpeptidase, another long term indirect biomarker that is routinely used and standardized in laboratory medicine.

A comparison between serum carbohydrate-deficient transferrin and hair ethyl glucuronide in detecting chronic alcohol consumption in routine

AIMS

In heavy alcohol consumption laboratory tests represent an objective evidence. In this study we compared older and newer biomarkers in blood and in hair.

METHODS

Carbohydrate-deficient transferrin (CDT), ethyl glucuronide (EtG), AST, ALT, GGT, MCV were measured in a large sample (n = 562). All people declared no alcohol consumption within the last 3 months. Serum CDT was measured by the candidate HPLC reference method and expressed as relative amount of disialotransferrin (%DST: cutoff 1.7%). EtG was measured in hair by a validated in-house method by LC-MS/MS (cutoff 30 pg/mg).

RESULTS

Respectively, 42 (7.5%) and 76 (13.5%) subjects were positive to CDT and EtG. In particular, 30 (5.3%) subjects were positive to both tests, 12 (2.1%) only to CDT, while 46 (8.2%) only to EtG. The agreement (positive and negative pairs) between CDT and EtG was 89.7%. Interestingly, 6 out of 12 (50%) CDT-positive subjects had EtG < 15 pg/mg, whereas 27 out of 46 (59%) EtG-positive subjects had CDT < 1.1%. Forty-one out of 76 (54%) EtG-positive subjects display EtG values within 30-50 pg/mg.

CONCLUSION

Large variability exists between CDT and EtG in detecting chronic alcohol consumption. We suggest to use CDT, or a combination of different biomarkers, to identify alcohol abuse in a forensic context. EtG results close to the cutoff (30-50 pg/mg) should be cautiously considered before any sanction is assigned.

Diagnostic sensitivity of carbohydrate deficient transferrin in heavy drinkers

Background and Aim

Carbohydrate deficient transferrin (CDT) is the most specific serum biomarker of heavy alcohol consumption, defined as ≥ 350–420 g alcohol/week. Despite introduction of a standardized reference measurement technique, widespread use of CDT remains limited due to low sensitivity. The aim of this study was to determine the factors that affect diagnostic sensitivity in patients with sustained heavy alcohol intake.

Methods

Patients with a self-reported history of sustained heavy alcohol consumption were recruited from the hepatology outpatient department or medical wards. Each patient was interviewed with a validated structured questionnaire of alcohol consumption and CDT analysis using the standardized reference measurement technique with high performance liquid chromatography was performed on serum collected at time of interview.

Results

52 patients were recruited: 19 from the hepatology outpatient department and 33 from general medical wards. Median alcohol intake was 1013 (range 366–5880) g/week over the preceding two week period. 26 patients had a diagnostic CDT based on a threshold value of %CDT > 1.7 indicating heavy alcohol consumption, yielding a sensitivity of 50%. Overweight/obesity (defined as body mass index (BMI) ≥ 25 kg/m² in Caucasians and ≥ 23.0 kg/m² in Asians), female gender and presence of cirrhosis were independently associated with non-diagnostic %CDT (≤ 1.7).

Conclusions

CDT has limited sensitivity as a biomarker of heavy alcohol consumption. Caution should be applied when ordering and interpreting %CDT results, particularly in women, patients with cirrhosis and those with an elevated BMI.

False negativity to carbohydrate-deficient transferrin and drugs: a clinical case

Introduction:

In this work we report on the possible effect of the medical therapy on CDT concentration in a chronic alcohol abuser, with known medical history (July 2007 – April 2012) and alcohol abuse confirmed by relatives.

Case history:

At the end of 2007, patient displayed the following laboratory results: AST 137 U/L, ALT 120 U/L, GGT 434 U/L, MCV 101 fL and CDT 3.3%. On December 2007, after double coronary artery bypass surgery, he began a pharmacological treatment with amlodipine, perindopril, atorvastatin, isosorbide mononitrate, carvedilol, ticlopidine and pantoprazole. In the next months, until may 2011, the patient resumed alcohol abuse, as confirmed by relatives; however, CDT values were repeatedly found negative (0.8% and 1.1%) despite elevated transaminases and GGT, concurrent elevated ethyl glucuronide concentration (> 50 mg/L) and blood alcohol concentration (> 1 g/L). Alcohol consumption still continued despite increasing disulfiram doses ordered by an Alcohol Rehab Center. On May 2011, the patient was transferred to a private medical center where he currently lives.

Conclusions:

This study suggests the possibility that a medical therapy including different drugs may hamper the identification of chronic alcohol abusers by CDT.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Monitoring population levels of alcohol consumption in pregnant women: a case for using biomarkers

A challenge to biochemically monitoring alcohol consumption in pregnancy is the prohibitive costs of collecting thousands of blood samples. This pilot study looks at the feasibility of using residual samples to monitor chronic and acute alcohol consumption in pregnancy. Residual anomalies screening samples (n = 150, 2006/7) were tested for carbohydrate-deficient transferrin (CDT, chronic marker) and ethyl glucuronide (EtG, acute marker). Valid readings were obtained for CDT but not EtG. These results pave the way for a larger representative study, to provide, for the first time, a national biochemical baseline estimate of chronic alcohol consumption in the pregnant population.

Effect of transferrin glycation on the use of carbohydrate-deficient transferrin as an alcohol biomarker

AIMS

Measurement of an alcohol-induced shift in the serum transferrin glycosylation pattern, termed carbohydrate-deficient transferrin (CDT), is used as a biomarker for sustained high alcohol consumption. The present work examined whether non-enzymatic reaction of transferrin with glucose (glycation) might interfere with the use of CDT as an alcohol biomarker.

METHODS

The blood specimens were leftover volumes from the routine sample pool. Plasma and serum were collected among samples submitted for hemoglobin A1c (HbA1c) and CDT testing. Quantification of individual transferrin glycoforms in percentage of total transferrin was performed by an HPLC candidate CDT reference method.

RESULTS

Incubating serum spiked with 20 or 200 mmol/l glucose caused time- and dose-dependent changes in the chromatographic profile of transferrin glycoforms, resulting in gradually wider peaks and reduced relative amounts of disialo- and trisialotransferrin. No similar chromatographic effects were seen in samples collected from diabetic patients with elevated HbA1c (>68 mmol/mol) values. These samples instead showed slightly higher mean %disialotransferrin levels (1.21%) compared with low HbA1c (<44 mmol/mol) samples (mean 1.06%; P = 0.023), pointing at a higher alcohol consumption level in the former group. Altogether ∼5% of the CDT values exceeded the cutoff. There was no significant difference in phosphatidylethanol (PEth) levels between the high and low HbA1c samples, but several (∼14%) showed elevated PEth concentrations.

CONCLUSION

Glycation of serum transferrin in vivo was indicated to differ from that in vitro, and suggested not to interfere with %CDT testing by the HPLC method. The results indicated that CDT and PEth are useful as objective, complementary alcohol biomarkers to identify risky drinking also in diabetic subjects.

The treatment of alcohol and opioid dependence in pregnant women

PURPOSE OF REVIEW

This article addresses the question of 'best treatment options', which clinicians face when treating pregnant women with alcohol and opioid dependence.

RECENT FINDINGS

Studies show that alcohol consumption is associated with fetal abnormalities and long-term cognitive problems depending on the amount consumed, drinking pattern, and time of gestation. Screening and evaluation of specific interventions are important to reduce alcohol consumption during pregnancy and associated problems in infants. Opioid detoxification is only recommended beyond the first trimester and only in those pregnant women who refuse opioid maintenance therapy. Methadone is the most established treatment of pregnant opioid-dependent women, though recent results indicate some advantages of buprenorphine, slow-release oral methadone and diamorphine compared with methadone.

SUMMARY

Benzodiazepines seem to be the most recommendable option for managing alcohol withdrawal, and psychosocial interventions succeed in reducing alcohol consumption or in maintaining abstinence in alcohol-dependent pregnant women. Regarding opioid dependence, current results suggest that factors like the health status of the mother, the need for additional medications (e.g. treatment for HIV), comorbid drug dependence, and concurrent drug use need to be considered in order to find the 'best opioid substitute'.

Advanced gestational age increases serum carbohydrate-deficient transferrin levels in abstinent pregnant women

AIMS

Carbohydrate-deficient transferrin (%CDT) is a well-established and highly specific biomarker for sustained heavy consumption of alcohol. However, in pregnant women, the specificity of this biomarker might be affected by advanced gestational age, even after accounting for increased transferrin concentrations in pregnancy. The goal of this prospective study was to assess the variability in %CDT during pregnancy among alcohol-abstaining patients.

METHODS

Patients were recruited during one of the first prenatal care visits and followed-up to term. Abstinence was confirmed by maternal self-report and by alcohol biomarkers. Biomarkers assessed in the mother included serum gamma-glutamyltranspeptidase, urine ethyl glucuronide and ethyl sulfate, and whole blood phosphatidylethanol (PEth). In addition, PEth was measured in a dry blood spot card obtained from a newborn. For %CDT analysis, serum samples were collected at baseline and at term and analyzed by an internationally validated high-performance liquid chromatography and spectrophotometric detection method.

RESULTS

At recruitment (mean gestational age 22.6 ± 7.3 weeks), the mean %CDT concentration was 1.49 ± 0.30%, while at term, it increased to 1.67 ± 0.28% (P = 0.001). Using a conventional cutoff concentration %CDT >1.7%, 22.9 and 45.7% of the sample would be classified as 'positive' for this biomarker at recruitment and at term, respectively (P = 0.011 ).

CONCLUSION

These results suggest that a conventional cutoff of 1.7% might be too low for pregnant women and would generate false-positive results. We propose that %CDT >2.0% be used as a cutoff concentration indicative of alcohol exposure in pregnant women. The sensitivity of %CDT at this cutoff for heavy drinking during pregnancy needs to be assessed further.

Alcohol consumption among pregnant women in a Swedish sample and its effects on the newborn outcomes

BACKGROUND

Little is known about the effects of low levels of maternal alcohol intake on the neuropsychological development of the child. This study is part of an ongoing investigation on maternal drinking and presents data on demographic variables, maternal alcohol use, and birth outcomes from that study.

METHODS

The sample comprised 2,264 women from a Swedish antenatal clinic. Retrospective self-report data were collected on alcohol consumption before and during pregnancy, using the Alcohol Use Disorders Identification Test (AUDIT), and on nicotine use. Specific alcohol biomarkers for excessive drinking, carbohydrate-deficient transferrin (CDT) in serum and phosphatidylethanol (PEth) in whole blood, were determined during mid-pregnancy in a subsample of the women. Data on labor and early characteristics of the child were also assessed.

RESULTS

Before pregnancy, 89% of the women regularly consumed alcohol and 49% reported occasional or frequent binge drinking. Nicotine was used by 15% before and by 5% during pregnancy. During pregnancy, 12% continued using alcohol and 5% also admitted binge drinking. However, all alcohol biomarker values were below the reporting limits (CDT ≤ 1.7% disialotransferrin; total PEth < 0.1 μmol/L). Self-reported drinking during pregnancy was associated with a higher AUDIT score before pregnancy, nicotine use at the time of the first prenatal visit, older age, and previous legal abortions.

CONCLUSIONS

The AUDIT questionnaire and 2 specific alcohol biomarkers were used in routine maternity care to collect information about drinking during pregnancy and thereby to identify children at risk for alcohol-related complications. While the AUDIT results suggested that a significant number of women continued using alcohol during pregnancy, implying a risk for fetal disorders, the biomarkers showed negative test values thus indicating only modest drinking levels.

High performance liquid chromatography evaluation of serum carbohydrate-deficient transferrin and more sialylated transferrin glycoforms in children

OBJECTIVES

The evaluation of the age-specific distribution of transferrin glycoforms in paediatric patients may help in defining reference intervals which are critical for an improved and earlier diagnosis.

DESIGN AND METHODS

Serum samples from 224 children (age: 2 months-14 years) were analyzed by HPLC (Bio-Rad CDT/HPLC kit) and glycoforms expressed as percentage of the total area of transferrin (Tf).

RESULTS

Asialo- and Monosialo-Tf were not detectable in any patient. Medians (IQR) were respectively 0.92% (0.80-1.04%) for Disialo-Tf; 3.47% (2.69-4.18%) for Trisialo-Tf; 82.54% (81.32-83.53%) for Tetrasialo-Tf; 12.73% (11.91-14.09%) for Pentasialo-Tf. Statistically significant differences in Trisialo-Tf (p < 0.0005), Tetrasialo-Tf (p = 0.001), Pentasialo-Tf (p < 0.0005), but not in Disialo-Tf, were observed between the age groups.

CONCLUSIONS

Age-specific Disialo-Tf cut-offs are not necessary. In children 1.3% and 6.4% may be suggested as upper limits of normal range to detect increases of Disialo- and Trisialo-Tf. The presence of Asialo- and Monosialo-Tf should be considered an abnormal finding and prompt further investigations.