Elevated circulating platelet-derived microparticles in patients with active inflammatory bowel disease

OBJECTIVES: Platelet-derived microparticles (PDMPs) are active molecules involved in the hemostatic and inflammatory responses. To evaluate the changes in the platelet function in patients with inflammatory bowel disease (IBD), we measured circulating PDMP levels. METHODS: Twenty-five healthy controls, 44 patients with ulcerative colitis (UC), and 43 patients with Crohn's Disease (CD) were studied. The PDMP and soluble P-selectin (sP-selectin) levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: In the healthy controls, the PDMP levels were 17.2 +/- 6.2 U/mL. Significant differences were not observed between the healthy controls and inactive UC patients (20.8 +/- 9.5 U/mL, n = 25) or between the healthy controls and inactive CD patients (17.6 +/- 7.8 U/mL, n = 24). In contrast, the PDMP levels were significantly higher in both active UC (49.2 +/- 33.6 U/mL, n = 19) and active CD (48.6 +/- 42.8 U/mL, n = 19) patients than in the healthy controls. A significant correlation was found between the PDMP levels and the clinical activity indexes (CAI) of UC patients (r = 0.65, p < 0.01, n = 44), and between the PDMP levels and Crohn's disease activity indexes (CDAI) (r = 0.72, p < 0.01, n = 43). Elevated PDMP levels in active patients were significantly reduced after remission. A significant correlation was observed between the PDMP levels and the sP-selectin levels (r = 0.60, p < 0.01, n = 122). CONCLUSION: Elevated circulating PDMPs in active IBD patients suggest a role for platelets in the pathogenesis of IBD.