Haemorheological alterations in Behcet's disease are not related to a tendency for venous thrombosis

Introduction: Behet's disease is associated with an increased risk of thrombosis, although the prothrombotic mechanisms are unclear. Alterations in blood rheology, particularly increased erythrocyte aggregation, might play a role in the development of such thrombotic events. Materials and methods: We measured plasma lipids, fibrinogen, haematocrit, erythrocyte aggregation, erythrocyte deformability, blood viscosity, plasma viscosity and erythrocyte indexes in patients with a nonactive disease at sampling, and in a well-matched control group. The patient group comprised 42 patients with BD (21 mate, 21 female aged 43 12 years) and the control group comprised 46 healthy volunteers (23 mate, 23 female aged 45 13 years). Twelve of the 42 patients with BD had a previous documented history of deep vein thrombosis at least 6 months before entering the study, and the other 30 did not. Results: Compared with controls, patients showed statistically higher fibrinogen concentrations (P=0.001), plasma viscosity (P=0.002), blood viscosity (P=0.006) and erythrocyte aggregation, both at stasis (P=0.001) and at a tow shear rate (P=0.002): the other rheological parameters were not statistically significant. No differences were observed in the rheological parameters when patients with and without previous thrombotic episodes were compared. Conclusions: Although patients with BD show a moderate hyperviscosity syndrome, possibly related to chronic inflammation, this does not seem to play a rote in the development of thrombotic events. (C) 2004 Elsevier Ltd. All rights reserved.