[The new "alcohol marker" carbohydrate-deficient transferrin (CDT). Value for neurologic-psychiatric diagnosis]

Many alcoholics deny any abuse, and hence it is often difficult to diagnose alcohol abuse. Laboratory parameters, such as gamma-glutamyltransferase (gamma-GT) and the mean corpuscular volume of erythrocytes (MCV), are often used to diagnose recent high alcohol intake. However, these parameters indicate elevated alcohol consumption only indirectly, e.g. if the elevation is due to an organ lesion caused by alcohol. In recent literature, CDT (carbohydrate-deficient transferrin) has been suggested as a most promising laboratory parameter indicating noxious alcohol consumption. The clinical value of CDT is compared to other "alcohol markers". CDT has the highest sensitivity and specificity in selected samples taken from alcoholics. However, the sensitivity of CDT is rather low in population surveys. Thus, CDT cannot be recommended for the screening of alcoholics. Furthermore, in view of the high cost of measurement, a close indication for application is urgent. Some examples of an indication in neurological and psychiatric diagnostics are critically discussed.