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HelpTest Code CDTA Carbohydrate Deficient Transferrin, Adult, Serum
Reporting Name
Carb Def Transferrin, Adult, SUseful For
Indicating chronic alcohol abuse
This test is not appropriate for screening patients for congenital disorders of glycosylation.
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
SerumOrdering Guidance
This test is for evaluation of alcohol abuse. If the ordering physician is looking for congenital disorders of glycosylation, order CDG / Carbohydrate Deficient Transferrin for Congenital Disorders of Glycosylation, Serum.
Necessary Information
1. Patient's age is required.
2. Reason for testing is required if patient is younger than 21 years.
Specimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.1 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Specimen Minimum Volume
0.05 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum | Frozen (preferred) | 45 days | |
| Refrigerated | 28 days | ||
| Ambient | 7 days |
Reference Values
≤0.10
0.11-0.12 (indeterminate)
Day(s) Performed
Wednesday
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
82373
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| CDTA | Carb Def Transferrin, Adult, S | 53803-3 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 31714 | Mono-oligo/Di-oligo Ratio | 35469-6 |
| 31715 | Interpretation | 59462-2 |
Clinical Information
Chronic alcoholism causes a transient change in the glycosylation pattern of transferrin where the relative amounts of disialo- and asialotransferrin (carbohydrate deficient transferrin: [CDT]) are increased over the amount of normally glycosylated tetrasialotransferrin. This recognition led to the use of CDT in serum as a marker for chronic alcohol abuse.
CDT typically normalizes within several weeks of abstinence of alcohol use. However, it is important to recognize that there are other causes of abnormal CDT levels, which include congenital disorders of glycosylation and other genetic and nongenetic causes of acute or chronic liver disease.
CDT testing alone is not recommended for general screening for alcoholism; however, when combined with other methods (ie, gamma-glutamyltransferase, mean corpuscular volume, patient self-reporting, ethylglucuronide analysis), clinicians can expect to identify the majority of patients who consume a large amount of alcohol.
Interpretation
Patients with chronic alcoholism may develop abnormally glycosylated transferrin isoforms (ie, carbohydrate deficient transferrin: CDT >0.12). CDT results from 0.11 to 0.12 are considered indeterminate.
Patients with liver disease due to genetic or nongenetic causes may also have abnormal results.
Cautions
This assay has not been fully validated for the investigation of alcoholism.
Carbohydrate deficient transferrin (CDT) testing alone is not recommended for general screening for alcoholism. Analysis of more than one biomarker is recommended to avoid misinterpretation of results.
The abnormal transferrin isoform pattern in patients with chronic alcoholism is similar to that observed in congenital disorders of glycosylation (CDG). However, unlike most patients with CDG, the relative amount of monoglycosylated transferrin is much lower. Other conditions such as hereditary fructose intolerance, galactosemia, and liver disease may result in increased levels of CDT. In addition, preanalytic variables such as bacterial contamination may cause falsely elevated CDT values. Several factors may cause variability in CDT analysis, including ethnicity, gender, pregnancy, body mass index, smoking, blood pressure, iron metabolism, drug interactions, chronic medical illness.
Clinical Reference
1. De Giovanni N, Cittadini F, Martello S. The usefulness of biomarkers of alcohol abuse in hair and serum carbohydrate-deficient transferrin: a case report. Drug Test Anal. 2015;7(8):703-707
2. Fleming MF, Anton RF, Spies CD. A review of genetic, biological, pharmacological, and clinical factors that affect carbohydrate-deficient transferrin levels. Alcohol Clin Exp Res. 2004;28(9):1347-1355
3. Gough G, Heathers L, Puckett D, et al. The Utility of Commonly Used Laboratory Tests to Screen for Excessive Alcohol Use in Clinical Practice. Alcohol Clin Exp Res. 2015;39(8):1493-1500
4. Shibamoto A, Namisaki T, Suzuki J, et al. Clinical significance of gamma-glutamyltranspeptidase combined with carbohydrate-deficient transferrin for the assessment of excessive alcohol consumption in patients with alcoholic cirrhosis. Medicines (Basel). 2021;8(7):39
5. Torrente MP, Freeman WM, Vrana KE. Protein biomarkers of alcohol abuse. Expert Rev Proteomics. 2012;9(4):425-436
Method Description
This method is a qualitative assay that measures transferrin isoform ratios using a combination of immunoaffinity capture and liquid chromatography-mass spectrometry analysis.(Lacey JM, Bergen R, Magera MJ, et al: Rapid determination of transferrin isoforms by immunoaffinity liquid chromatography and electrospray mass spectrometry. Clin Chem. 2001; Mar;47(3):513-518; Helander A, Wielders J, Anton R, et al. Standardisation and use of the alcohol biomarker carbohydrate-deficient transferrin [CDT], Clin Chim Acta. 2017;467:15-20 doi:10.1016/j.cca.2017.03.018)
Report Available
3 to 9 daysSpecimen Retention Time
1 monthReject Due To
| Gross hemolysis | OK |
| Gross lipemia | OK |
| Gross icterus | OK |
Method Name
Affinity Chromatography/Mass Spectrometry (MS)
Highlights
Patients with chronic alcoholism demonstrate increased levels of carbohydrate deficient transferrin over the amount of normally glycosylated tetrasialotransferrin.
Forms
If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.