N Latex CDT AssayHighly specific screening for detection of chronic alcohol abuse

N Latex CDT Assay

The N Latex CDT assay for use on Atellica^® NEPH 630, BN™ II and BN ProSpec^® Systems provides a highly specific screening method for the detection of alcohol abuse. The CDT level increases and decreases with the amount of alcohol consumed; therefore, many different applications are possible, such as differential diagnosis of alcohol-induced versus nonalcohol-induced diseases, legal applications (e.g., for regranting of driver’s license), workplace testing, or forensic toxicology.

Fully automated immunoassay with no sample pretreatment required
Highly specific monoclonal antibody that directly detects CDT
Automatic calculation of %CDT by running CDT and transferrin assays simultaneously
Fast availability of results—within 20 minutes (total assay time)
Random-access capability
Reliable results—excellent recovery between labs, systems, and lots

Features & Benefits

Carbohydrate-deficient transferrin (CDT) is regarded as a very specific marker for identifying excessive alcohol consumption and monitoring abstinence during outpatient treatment.

Regular alcohol consumption of more than 50–80 g of ethanol per day for at least 2 weeks can result in a changed glycosylation pattern of transferrin, leading to a higher rate of isoforms lacking one or both entire carbohydrate chains. These isoforms (disialo- and asialotransferrin) are collectively named carbohydrate-deficient transferrin (Figure 1). After approximately 2–4 weeks of abstinence, CDT concentrations usually return to normal levels.

Compared to other markers, CDT offers superior sensitivity and specificity:^1,2

CDT is seemingly unaffected by liver diseases other than those induced by alcohol abuse (except biliary cirrhosis and chronic active hepatitis).
CDT is not influenced by common chronic diseases or medication.
CDT indicates the effectiveness of alcohol detoxification much earlier than gamma-glutamyl transferase or erythrocyte mean corpuscular volume, for example.

Based on an assumed cutoff of 2.5 %CDT, test results obtained with N Latex CDT on BN™ Systems exhibit a specificity of 97% and a sensitivity of 93% in comparison to the %CDT values determined with HPLC.³

Technical Specifications

Assay principle	Latex-enhanced immunonephelometry
Sample type	Human serum
Measuring time	18 minutes
Reference range	28.1–76 mg/L (1.19–2.47% CDT)⁴
Initial measuring range	20–660 mg/L
Once-opened reagent stability	2 weeks on Atellica NEPH 630 and BN ProSpec^® Systems 3 days (6 days with evaporation stoppers) on BN™ II System
Calibration frequency	2 weeks
Precision	Repeatability: <4.5% Within-lab: <2.0%

Services & Support

Education & Training

Allen AP. Use of biomarkers of heavy drinking in health care practice. Military Medicine. 2003;168(5):364-367.

Madhubala V, et al. Serum carbohydrate deficient transferrin as a sensitive marker in diagnosing alcohol abuse: a case-control study. J Clin Diagn Res. 2013;7(2):197-200.

Delanghe JR, et al. Development and multicenter evaluation of the N Latex CDT direct immunonephelometric assay for serum carbohydate-deficient transferrin. Clin Chem. 2007;53:1115-21.

%CDT results determined with N Latex CDT assay in concurrence with N antiserum to human transferrin (1st to 99th percentile)

The products/features shown on this web page are not commercially available in all countries. Due to regulatory reasons their future availability cannot be guaranteed. Please contact your local Siemens organization for further details.