Test ID CDTA Carbohydrate Deficient Transferrin, Adult, Serum
Useful For
An indicator of chronic alcohol abuse
Method Name
Affinity Chromatography/Mass Spectrometry (MS)
Reporting Name
Carb Def Transferrin, Adult, SSpecimen Type
SerumCollection Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 0.1 mL
Additional Information:
1. Patient's age is required. Reason for referral is required if patient is <21 years old.
2. 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.
Specimen Minimum Volume
0.05 mL
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Serum | Frozen (preferred) | 45 days |
Refrigerated | 28 days | |
Ambient | 7 days |
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 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 non-genetic 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.
Reference Values
≤0.10
0.11-0.12 (indeterminate)
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 (CDGs). However, unlike most patients with CDG, the relative amount of mono-glycosylated transferrin is much lower. Other conditions such as hereditary fructose intolerance, galactosemia, and liver disease may result in increased levels of CDT. In addition, pre-analytical 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.
Day(s) Performed
Wednesday; 8 a.m.
Report Available
5 days (Not reported Saturday or Sunday)Performing Laboratory

Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.CPT Code Information
82373