title: Circulated activated platelets and increased platelet reactivity in patients with Behçet's disease.
abstract: Behçet's disease (BD) is a multisystem disorder. Venous as well as arterial thrombosis is a common complication of BD but exact pathogenetic mechanism of the thrombotic tendency is not well known. This study aimed to evaluate circulating activated platelets and platelet reactivity in Behçet's patients. Twenty-two Behçet's patients (4 female, 18 male; mean age 38.6 +/- 10.9 years) and 20 control subjects (8 female, 12 male; mean age 38.8 +/- 9.4 years) were included. Those patients who had hypertension, hyperlipidemia, peripheral or coronary artery disease, hepatic or renal function abnormality, and who were using aspirin and other platelet-active drugs were excluded. Platelet activity and reactivity to adenosine diphosphate (ADP) were measured by whole blood flow cytometry. We assessed markers of platelet degranulation (P-selectin; CD62P) and the activated glycoprotein IIb/IIIa receptor (PAC1 binding to fibrinogen binding site) before and after stimulation with ADP. Platelet P-selectin expression was not significantly different between patients and control subjects both at baseline (p=0.420) and after stimulation (p=0.56). Baseline (p=0.001) and ADP-stimulated (p=0.003) PAC1 binding was significantly higher in Behçet's patients than in the control group. Clinical activity has no effect on P-selectin expression and PAC1 binding. There is evidence of platelet activity and hyperreactivity in patients with BD and this may contribute to a prothrombotic state. In addition to aspirin, other antiplatelet drugs may be useful in the prevention and treatment of thrombosis in Behçet's patients.
authors.affiliation: Department of Internal Medicine, School of Medicine, Dokuz Eylul University, Izmir, Turkey.
authors.forename: Servet
authors.initials: S
authors.lastname: Akar
authors.forename: Mehmet Ali
authors.initials: MA
authors.lastname: Ozcan
authors.forename: Halil
authors.initials: H
authors.lastname: Ateş
authors.forename: Oğuz
authors.initials: O
authors.lastname: Gürler
authors.forename: Inci
authors.initials: I
authors.lastname: Alacacioglu
authors.forename: G Hayri
authors.initials: GH
authors.lastname: Ozsan
authors.forename: Nurullah
authors.initials: N
authors.lastname: Akkoç
authors.forename: Sebnem
authors.initials: S
authors.lastname: Ozkan
authors.forename: Fatih
authors.initials: F
authors.lastname: Demirkan
authors.forename: Fatos
authors.initials: F
authors.lastname: Onen
mesh_terms: D000328:Adult; D001528:Behcet Syndrome / Q000097:blood* / Q000628:therapy*; D002097:C-Reactive Protein / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019007:P-Selectin / Q000097:blood; D018579:Patient Selection; D015539:Platelet Activation; D012016:Reference Values
chemical_list: D019007:P-Selectin; D002097:C-Reactive Protein