Evaluation of carbohydrate-deficient transferrin compared with Tf index and other markers of alcohol abuse.

It has been known for some years that a partial deglycosylation of transferrin occurs in the sera of alcohol abusers. Different methods have been proposed in order to evaluate this carbohydrate-deficient fraction of serum transferrin. Chromatofocusing or isoelectric focusing followed by direct immunofixation have been used until now. Recently, a new method called the carbohydrate-deficient transferrin (CDT) test based on ion-exchange chromatography has been developed by Stibler et al. (Alcohol Clin Exp Res 10:535-544, 1986). Here we compare this new method with results obtained using our Tf index determination method. The upper limit of normal values was set to the 90th percentile of the values observed in a reference population. The population under investigation consisted of 50 healthy volunteers and 160 alcohol abusers whose ethanol consumption was evaluated through a questionnaire. Sensitivity and specificity of the CDT test have been found higher than 0.76 and 0.90, respectively. The correlation between both methods was 0.794, a satisfactory result considering that the CDT test and the Tf index do not exactly measure the same part of the carbohydrate-deficient transferrin. In a population of 23 patients with liver diseases not related to alcohol abuse, no abnormal CDT value was observed. We can conclude from these results that the CDT test now seems to be the best test to detect alcohol abusers.

Kinetics of serum glutamate dehydrogenase during short-term alcohol withdrawal.

The behavior of serum glutamate dehydrogenase after alcohol withdrawal was studied in 64 alcoholics admitted to a detoxification center. The enzyme activity decreased in 57 patients by a median of -35.8 percent in 24 h. Thus, the decrease of serum glutamate dehydrogenase after 24 h of ethanol abstinence can serve as a test of alcohol abuse.

The decrease of low serum gamma glutamyl transferase during short-term abstinence.

We present a study of 107 in-patients of a detoxification center. As expected, 81 percent of them showed upon admittance an increased serum gamma glutamyl transferase (GGT). After alcohol withdrawal, GGT decreased in all but one of these patients. More surprisingly, even among the rest of the patients exhibiting upon admittance a GGT result within the reference range, there still occurred a significant decrease in 50 percent of the cases. Thus, whether the initial GGT is high or normal, we observed a decrease in 96 patients out of 107, i.e., a sensitivity of 0.90. The decrease test consists in asking a subject to refrain from any alcohol intake during a short period, e.g., seven days. If any significant diminution of serum GGT occurs, the possibility of alcohol abuse should at least be given serious consideration before being rejected. This test was used up to now only when GGT was initially high. The present results show that it can be attempted even when GGT is initially within the normal range, with a sensitivity of 0.90.