Objectives: Pentraxin 3 (PTX3) plays an important role in inflammation, immunity, and atherosclerosis. Plasma PTX3 level has drawn attention as a marker that responds to local inflammation. Systemic lupus erythematosus (SLE), a chronic inflammatory disorder which can affect multiple organs, develops atherosclerosis prematurely. We examined the hypotheses that the concentration of plasma PTX3 increases in patients with SLE and that PTX3 is associated with the disease activity and premature atherosclerosis.
Methods: Plasma PTX3 concentrations were measured in 65 patients with SLE and 53 control subjects. The patients were also evaluated with respect to their clinical characteristics, disease activity indices, and corticosteroid therapy. We performed carotid ultrasonography to measure subclinical atherosclerosis in patients with SLE.
Results: Plasma PTX3 concentration of the SLE patients was significantly higher than that of the healthy controls (median 3.9 vs. 2.0 ng/mL, p < 0.001). In patients with SLE, PTX3 concentrations were correlated with SLEDAI (p = 0.011), BILAG index (p < 0.001), C-reactive protein (p < 0.001), anemia (p = 0.020), hypoalbuminemia (p = 0.022), and daily dose of prednisolone (p = 0.008) after adjustment for age and sex. PTX3 was not associated with disease duration, anti-ds DNA antibody, CH50, or carotid atherosclerosis.
Conclusions: Patients with SLE have increased concentrations of PTX3 compared with control subjects. PTX3 was significantly associated with disease activity but not with carotid atherosclerosis.