Automated measurement of carbohydrate-deficient transferrin using the Bio-Rad %CDT by the HPLC test on a Variant™ HPLC system:: Evaluation and comparison with other routine procedures

Aims: In this study, we evaluated the new %CDT by the HPLC method (Bio-Rad, Germany) on a Variant (TM) HPLC system (Bio-Rad), checked the correlation with well-known methods and calculated the diagnostic value of the test. Methods: Intra-run and day-to-day precision values were calculated for samples with extreme serum transferrin concentrations, high trisialotransferrin and interfering conditions (haemolysed, lactescent and icteric samples). The method was compared with two routine procedures, the %CDT TIA (Bio-Rad, Hercules, CA, USA) and the Capillarys (TM) CDT (Sebia, France). A total of 350 clinical sera samples were used for a case-control study. Results: Precision values were better in high CDT and medium CDT pools than in low CDT pools. The serum transferrin concentration had no effect on CDT measurement, except in samples with serum transferrin < 1 g/L. Haemolysis was the only interfering situation. The method showed high correlation (r(2) > 0.95) with the two other methods (%CDT TIA and CZE %CDT). The global predictive value of the test was > 0.90 at 1.9% cut-off. Conclusions: These results demonstrate that the %CDT by the HPLC test is suitable for CDT routine measurement; the results from the high-throughput Variant (TM) system are well correlated with other methods and are of high diagnostic value.