The significance of platelet activation in ankylosing spondylitis.

The objective of this study was to explore the significance of platelet activation in patients with ankylosing spondylitis (AS). Thirty-five AS patients and 15 normal controls were selected from November 2005 to October 2006. The number of CD62P- and CD63-positive cells were detected by flow cytometry. At the same time, the erythrocyte sedimentation rate (ESR), platelet count (PLT) and C-reactive protein (CRP) were determined in both groups. The percentage of CD62P-positive cell in AS patients (13.60 +/- 7.64%) was significantly higher than that in control group (2.78 +/- 1.04%; P < 0.01). The percentage of CD63-positive cell in AS patients (6.92 +/- 4.16%) was significantly higher than that in control group (4.13 +/- 1.85%; P < 0.05). The levels of CRP (20.18 +/- 23.17 mg/l), PLT (259.54 +/- 102.59 x 10(9)/l) and ESR (36.86 +/- 31.23 mm/h) in AS patients were higher than those in normal controls, respectively (3.21 +/- 2.18 mg/l, P < 0.01; 197.00 +/- 55.70 x 10(9)/l, P < 0.01; 12.25 +/- 5.05 mm/h, P < 0.05). Platelet activation may be a sign of AS exacerbation.