IL-6 plasma levels were higher in patients with positive BAL fluid cultures (5.2 ± 4.8 pg/ml) than in patients without infections (3.3 ± 7.8 pg/ml; p = 0.003), and a similar trend was found in CRP serum levels (12.6 ± 13.0 mg/l vs 5.7 ± 5.7 mg/l; p = ns). Here, CRP is linked to infection.