Serum IL-8 levels were higher in patients with Legionella pneumonia (n = 18) (189 ± 493 pg/ml) than in normal healthy controls (n = 16) (9.79 ± 15.06 pg/ml), although this difference was not statistically significant (P = 0.157). Here, CXCL8 is linked to Legionnaires' disease.