IL6 and cystic fibrosis: Regarding the correlations between cytokines and the lung disease severity in CF patients significant correlations were observed only in CF children: i) Spearman’s rank-order analysis showed a positive significant correlations between IL-8 and FEV1 (rs: 0.388; p=0.031); ; ii) IL-6 positively correlated with FEV1/age ratio, an index of lung disease severity (rs: 0.412; p=0.019).