Application and concentration selection of dithiothreitol for correcting false elevation of D-dimer.

BACKGROUND

Immunological methods for D-dimer detection are prone to interference, leading to falsely elevated values. This study evaluates the optimal concentration and corrective efficacy of dithiothreitol (DTT) in addressing false D-dimer elevations.

METHODS

Plasma samples from seven patients with falsely elevated D-dimer levels, identified using the Sysmex CS5100 coagulation analyzer, were analyzed. Correction was performed using the Stago STA-R Max analyzer with alternative detection antibodies. Additionally, plasma samples from thirty patients with confirmed D-dimer elevations were treated with varying concentrations of DTT (0.01, 0.05, 0.10, and 0.20 mol/L) and normal saline (NS). The optimal concentration of 0.01 mol/L DTT was identified and applied to the experimental group. The results were compared with those obtained using an alternative immunoassay method.

RESULTS

In the true elevation group, samples treated with 0.01 mol/L DTT showed no significant difference in D-dimer levels compared to the NS control or original results (all P > 0.05). Higher concentrations of DTT significantly lowered D-dimer levels compared to the NS group (all P < 0.05). In the experimental group, 0.01 mol/L DTT treatment and the alternative immunoassay method similarly reduced D-dimer levels, with no significant difference between the two correction methods (P > 0.05).

CONCLUSION

A 0.01 mol/L DTT solution effectively corrects falsely elevated D-dimer levels without affecting true elevations, yielding results comparable to those achieved by changing the immunoassay method.