Carbohydrate Deficient Transferrin

Carbohydrate Deficient Transferrin measures the proportion of transferrin in your blood that lacks some of its usual carbohydrate side chains. Transferrin is a protein made by the liver that carries iron. When fewer carbohydrates are attached, the protein is called carbohydrate deficient transferrin.

This pattern can change with sustained heavy alcohol use and in certain medical conditions that affect how the body attaches sugars to proteins. The test is typically reported as a percentage of total transferrin and is used alongside your history and other labs to understand your health.

Healthcare professionals use this test to help detect and monitor sustained heavy alcohol intake, to support treatment planning, and to follow progress during recovery. It can also provide clues when there are unexplained changes in liver tests or when a disorder that affects protein glycosylation is suspected.

Results are most useful when interpreted with your symptoms, medication list, and other tests such as liver enzymes or complete blood count. The test requires a standard blood draw. Risks are minimal and include brief discomfort or bruising at the needle site.

A higher percentage can suggest ongoing heavy alcohol use, but other conditions can also raise the result, including some liver diseases and rare inherited disorders of glycosylation. Pregnancy and iron status may shift transferrin patterns and can influence interpretation.

A result within the expected range does not rule out unhealthy drinking, especially if alcohol use is infrequent or recent. If your result is unexpected, your clinician may review your history, consider repeat testing after a period of abstinence, or order additional tests to look for liver disease, genetic variants, or other explanations.