Background: Because persistent inflammation plays a dominant role in cystic fibrosis (CF), we assessed systemic and local upper airway responses during and after pulmonary exacerbation. Methods: We followed a cohort of Psetidomonas aeruginosa-infected adult CF patients (n = 16) over time in pulmonary exacerbation and in stable disease. Interleukin (IL)-1 beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-17A, IL-22, interferon-gamma and TNF alpha levels were measured in sputum, nasal lavages and plasma. Results: In CF patients IL-6 and IL-10 levels in nasal lavages were significantly increased in exacerbation compared with stable disease. Systemic IL-6 significantly correlated with CRP levels and FEV1 (%predicted), independently of disease status. Systemic IL-10 also correlated significantly with CRP and FEV1 (%predicted), but only in exacerbation. Other cytokines tested did not discriminate between exacerbation and stable disease. Conclusions: Determination of IL-6 and IL-10 nasal lavages may provide a minimally invasive tool in the assessment of an exacerbation in CF. (C) 2013 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.