Significance of serum interleukin-8 levels in patients with Behcet's disease: high levels may indicate vascular involvement

Interleukin-8 (IL-8) has been shown previously to associate with different individual clinical manifestations and activity of Behcet's disease (BD), but its association with vascular involvement has not been established. Forty-five untreated patients with BD and 29 healthy individuals were included in the study. The activity of patients was based on the existence of two or more symptoms and a statistically significantly high Behcet's Disease Activity Index (BDAI) at the time of the study. IL-8, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) results were evaluated with respect to activity, vascular involvement, and other specific individual clinical manifestations of the disease. IL-8 levels were found to be significantly elevated in active BD compared with inactive BD (P = 0.006) and healthy controls (P = 0.000), with median values of 267 (53-2000), 137 (52-290), and 58 pg/mL (53-160 pg/mL), respectively. Unlike ESR and CRP, IL-8 levels showed a high correlation with BDAI scores (r = 0.743, P = 0.00) and the number of active clinical manifestations (r = 0.646, P = 0.00). Serum levels of IL-8 were increased in patients with oral ulcers, genital ulcers, eye lesions, and vascular lesions, with median values and significance levels of 254.5 (53-2000), P = 0.05; 254.5 (52-1400), P = 0.03; 254.5 (72-2000), P = 0.029; and 593 pg/mL (110-2000 pg/mL), P = 0.001, respectively. In addition, IL-8 levels in the active patient group with vascular involvement were significantly higher than the levels in those without vascular involvement. Serum IL-8 levels are increased in the active phase of BD. This marker may be useful in the early detection of vascular involvement.