Increased serum levels of interleukin-8 in polyarteritis nodosa and Behçet's disease.

The pathogenesis of Behçet's disease (BD) and polyarteritis nodosa (PAN) is not yet well established. Endothelial cells have been shown to express chemokines that are involved in inflammatory processes. Interleukin-8 (IL-8) is a potent chemoattractant and activator of neutrophils. We evaluated serum IL-8 levels in patients with PAN and BD. We measured serum IL-8 levels in 21 patients with BD and 16 with PAN. Sera from 30 age-matched healthy blood donors were used as normal controls. Serum IL-8 levels were measured by an enzyme-linked immunosorbent assay (ELISA). The mean serum IL-8 level of the active BD (1522.31 pg/ml) and that of the active PAN (654.8 pg/ml) was significantly higher than that of the normal controls (40.39 pg/ml, P <0.05). There was no difference in mean serum IL-8 levels between patients with inactive disease and normal controls. We found higher serum levels of IL-8 in those patients with more severe disease. These results suggest that IL-8 may play a role in the pathogenesis of PAN and/or BD. Our study also suggests a possible relation between serum IL-8 levels and the severity of these diseases.