Usefulness of carbohydrate-deficient transferrin in alcoholic patients with normal gamma-glutamyltranspeptidase.

The biological diagnosis of alcoholism is conducted routinely by assay of gamma-glutamyltranspeptidase (GGT) and mean corpuscular volume (MCV). However, their low specificity and sensitivity have prompted research to find other more reliable parameters. Stibler showed an increase in desialylated transferrin [carbohydrate-deficient transferrin (CDT)] in alcoholic patients. The normal value of the serum CDT concentration is under 60 mg/liter; a value between 60 and 100 mg/liter indicates probable alcoholism, and a value > 100 mg/liter indicates a very high probability of alcoholism (specificity: 99%). Its sensitivity ranges from 60 to 91%, and its specificity ranges from 92 to 100%. Its half-life is 17 +/- 4 days. CDT is thus a useful laboratory marker, but its assay is costlier and more complex than that of GGT. This study concerns 31 alcohol-dependent patients as defined by DSM-IV, with GGT levels in the normal range. It evaluates CDT at day 0 and its time course after 15 days withdrawal. GGT and MCV were assayed concomitantly. Remarkably, the results show a sensitivity of 83.9 (26 positives of 31) in this particular population and a specificity of 92.2. The fall in CDT after 15 days withdrawal was 36%. CDT is thus a particularly useful marker for the diagnosis and follow-up of alcoholics with normal GGT levels.

Application of HPLC with silica-phase and reversed-phase eluents for the determination of clomipramine and demethylated and 8-hydroxylated metabolites.

A rapid and efficient high-performance liquid chromatographic method using a reversed-phase eluent of methanol-water with butylamine on a silica column was developed for the separation and quantitation of clomipramine (CMI), its demethylated metabolites (desmethyl-clomipramine and didesmethyl-clomipramine [DDCMI]), and its hydroxylated metabolites (8-hydroxy-clomipramine and 8-hydroxy-desmethylclomipramine). A liquid-liquid extraction procedure, which involved an alkaline extraction with heptane-isoamyl alcohol, first from a 1-mL serum sample and then from the acidic back extract, was used. The chromatographic separation was rapid (20 min), and the ultraviolet detection (at 254 nm) was sufficiently sensitive (limit of detection, 5-10 ng/mL). Except for DDCMI, the calibration was linear (r > 0.99, n = 5), and within-day and day-to-day coefficients of variation remained less than 11%. The method was used to analyze CMI and its metabolites in the serum of depressive patients and to determine their hydroxylation and demethylation capacities.