Evaluating systemic lupus erythematosus disease activity using molecular markers of hemostasis

To determine the usefulness of measuring sensitive markers of the coagulation-fibrinolysis system (i.e., thrombin-antithrombin III complex [TAT], D dimer fragments [DD], and plasmin-alpha2-plasmin inhibitor complex [PIC]) for evaluating disease activity in patients with systemic lupus erythematosus (SLE).

We studied 57 SLE patients. Plasma concentrations of DD were measured by latex agglutination using monoclonal antibodies; TAT and PIC were determined by sandwich enzyme-linked immunosorbent assay. Disease activity was determined by using the SLE Disease Activity Index (SLEDAI).

Levels of TAT, DD, and PIC were higher in SLE patients than in healthy controls (P<0.05). Levels of TAT and DD showed good correlations with SLEDAI scores (for TAT r=0.66, P<0.001; for DD r=0.50, P<0.001). Elevated levels of TAT, DD, and PIC were decreased following treatment.

These results strongly suggest that measurement of molecular markers of hemostasis is useful for evaluating disease activity in patients with SLE.