Increased IL-6 and IL-4 in exhaled breath condensate of patients with nasal polyposis

Abstract

Nasal polyposis (NP) occurs in about 1-4% of the worldwide population. Increased plasma concentrations of different pro-inflammatory cytokines have been observed in NP, and might be related to the pathogenesis of this syndrome. The present study was designed to investigate IL-6 and IL-4 concentrations in nasal and oral exhaled breath condensate of patients with early and advanced NP, and following polypectomy. Ten individuals with polyposis in early status, twenty-three patients affected by advanced status of NP and ten healthy controls were enrolled into the study. Exhaled breath condensate was collected by all individuals, according to a previous standardised method. An immunoassay kit was used to measure IL-6 and IL-4 levels. Concentrations of oral and nasal exhaled IL-6 and IL-4 were significantly higher in patients with early nasal polyposis and advanced nasal polyposis, compared to healthy controls. A statistically significant decrease of nasally but not of orally exhaled IL-6 (p < 0.001) and IL-4 (p < 0.05) was observed after polypectomy. We consider oral and nasal exhaled condensate of IL-6 and IL-4 as valid inflammatory and oxidative stress marker in patients with nasal polyposis.