To evaluate the utility of plasma concentrations of lipoprotein (a) (Lp(a)) as an indicator of disease activity in Behçet's disease and to investigate its role in thrombotic complications of this disease.

30 patients (19 male, 11 female) with Behçet's disease (8 active, 22 inactive) were enrolled in the study group and 30 healthy individuals (16 male, 14 female) in the control group. Seven of the inactive Behçet's disease patients had a history of thrombotic complications. The disease activity was evaluated by clinical manifestations (oral aphthous lesions, genital ulcerations, uveitis and vasculitis) and laboratory investigations (leucocyte count, lipoprotein (a), C-reactive protein (CRP), complement 3 (C3) and complement 4 (C4) concentrations).

Plasma Lp(a) and other acute phase reactant concentrations were significantly higher in the study group than in the controls (p < 0.01). These concentrations were also higher during the active period of the disease than during the inactive phase (p < 0.01). Lp(a) concentrations were significantly correlated with concentrations of other acute phase reactants. There was no difference between the groups with and without thrombotic complications for any of these measurements.

Plasma levels of Lp(a) might be an indicator of disease activity in Behcet's disease. There is no correlation between Lp(a) levels and thrombotic sequela in inactive Behçet's disease. However, further studies are needed on the thrombogenic role of Lp(a) during the active phase of thrombophlebitis, and in larger series.