Exhaled inflammatory markers in aspirin-induced asthma syndrome

Background: Interleukin (IL)-4 and IL-6, respectively, markers of neutrophilic and eosinophilic inflammation, were analyzed in nasal and oral exhaled breath condensate to understand the inflammation of upper and lower airways in subjects with aspirin-induced asthma (AIA) syndrome, evaluating possible differences between AIA and the single pathological conditions included in AIA syndrome. Methods: Twelve patients with AIA, 17 patients with mild asthma (MA), 12 patients with nasal polyposis (NP), 11 patients with mild asthma + nasal polyposis (MA + NP), and 10 healthy subjects (HSs) were enrolled. Nasal and oral exhaled IL-4 and IL-6 were measured by enzyme immunoassay kit. Results: Higher levels of nasal and oral exhaled IL-4 and IL-6 were observed in AIA compared with MA, NP, MA + NP, and HSs. Moreover, a positive correlation was identified between nasal exhaled IL-4 and IL-6 and, respectively, the number of neutrophils and eosinophils and in nasal scraping. Conclusion: The concentration of eosinophilic and neutrophilic markers in upper and lower airways of subjects with AIA syndrome is higher compared with HS and subjects with MA, NP, and MA + NP.