To investigate whether plasma levels of Lp(a) lipoprotein (Lp(a)) are predictors of defective fibrinolytic activity, leading to thrombosis, in patients with Behçet's disease.
Plasma Lp(a) was measured by enzyme linked immunosorbent assay, lipids and lipoproteins by enzymatic methods, and apolipoproteins A-I and B, fibrinogen (turbidimetric method), tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), and D-dimer levels by enzyme immunoassay. Their levels and interactions were evaluated in 33 patients with Behçet's disease (including five with thrombotic complications) and 30 healthy control subjects.
Plasma Lp(a) concentration was significantly greater in the patients than in controls. Nine patients (27%) had levels > 0.30 microgram. There was no correlation between Lp(a) and other lipids and lipoproteins apart from apolipoprotein B. Lp(a) showed inverse correlation with t-PA (r = -0.34, p < 0.05) and D-dimer (r = 0.35, p < 0.05). Patients with thrombotic complications had significantly greater Lp(a) and PAI-1, and lower D-dimer concentrations than control subjects.
Measurement of plasma Lp(a) levels in patients with Behçet's disease may provide useful information regarding the potential development of thrombotic events, because of its possible role in defective fibrinolysis.