HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY IMPROVES DIAGNOSTIC EFFICIENCYOF CARBOHYDRATE-DEFICIENT TRANSFERRIN

Carbohydrate-deficient transferrin (CDT) is considered a useful bioche mical marker of regular high alcohol intake. CDT was measured in the s era of 51 alcohol abusers, 20 patients with nonalcoholic liver disease and 30 healthy controls with an alcohol intake of <30 g/day. The mean CDT levels of these three groups respectively were determined with hi gh-performance liquid chromatography (HPLC; 4.6 +/- 5.2%; 0.7 +/- 0.2% ; 0.7 +/- 0.2%) and with a radioimmunoassay after microcolumn anion-ex change chromatography (MAEC/RIA; 34.2 +/- 26.9 U/l; 16.9 +/- 3.8 U/l; 18.0 +/- 5.7 U/l). CDT levels in patients with severe alcohol abuse (1 61.6 +/- 96.4 g/day) were significantly higher than in the two other g roups under investigation (P < 0.0001). In heavily drinking subjects, the mean daily alcohol intake correlated with aspartate aminotransfera se levels (ASAT) but not with the CDT levels determined either with HP LC or MAEC/RIA. With both methods, the CDT levels were slightly higher in patients with an ASAT concentration >30 U/l, which may indicate an advanced liver damage (P < 0.05). Analysis of receiver-operating char acteristic (ROC) plots demonstrated that the diagnostic accuracy of th e HPLC method, which determines the relative amount of CDT, was signif icantly higher than the established MAEC/RIA method, which measures th e absolute amount of CDT (area under the ROC curve: 0.95 +/- 0.02 vs 0 .73 +/- 0.05; P < 0.0001). At a specificity of >95%, the sensitivity o f CDT determined with HPLC and MAEC/RIA was 80 and 47%, respectively. In addition, HPLC may be a useful and reliable method for the determin ation of this important biochemical marker, since the HPLC chromatogra m is a visible document of the successful isotransferrin separation an d measurement.