Summary
Thrombus formation is recognized pathologically in the affected arteries and is supposed
to play a major role in the pathogenesis of Takayasu’s arteritis; however, hemostatic
conditions in this disorder have not been elucidated fully. We determined plasma levels
of molecular markers for platelet activity (platelet factor 4; PF4, β-throm-boglobulin;
βTG), thrombotic status (thrombin-antithrombin III complex; TAT, fibrinopeptide A;
FPA), fibrinolytic status (plasmin-β2-plasmin inhibitor complex; PIC, D-dimer), and endothelial injury (von Willebrand
factor antigen; vWF:Ag, thrombomodulin; TM) in 30 patients with Takayasu’s arteritis
and in 20 age-matched control subjects. Plasma levels of PF4, βTG, TAT, FPA and D-dimer,
but not PIC, in patients with Takayasu’s arteritis were substantially higher than
those in normal control subjects. The levels of these markers were not different between
the active and inactive stages of the disease. Plasma levels of vWF:Ag in patients
with Takayasu’s arteritis did not differ significantly from those in normal subjects,
and plasma levels of TM were significantly lower than those in normal subjects. In
patients with Takayasu’s arteritis, platelet and coagulation activities are significantly
increased, leading to hypercoagulable state and thrombus formation, although there
is little, if any, endothelial damage.
