Carbohydrate Deficient Transferrin (CDT)

Diagnostic Use

Carbohydrate deficient transferrin (CDT) can be used to assess a patient's chronic alcohol consumption. The test does not correlate with the amount of alcohol consumed, but relates to the prolonged consumption of large quantities of alcohol. A single episode of heavy drinking will not elevate CDT levels.
CDT is reported as a percentage of total transferrin to reduce the effects of gender and varying transferrin concentrations.
CDT has a long half-life of 15 days. Under conditions of total abstinence it may take 1-2 months for CDT levels to return to normal.
The most reliable interpretation is obtained with a series of CDT tests to detect trends, with the tests being performed at 1-2 month intervals to allow for the long half-life of this protein.
False positive CDT results may occur in patients with severe liver disease, autoimmune hepatitis, biliary cirrhosis, liver cell cancer, haemochromatosis, transferrin variants and rarely congenital disorders of glycosylation.


Protein Lab

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Turnaround Time

1 week

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