The role of IL-25 and IL-33 in chronic rhinosinusitis with or without nasal polyps

The role of IL-25 and IL-33 in the aetiology and pathogenesis of nasal polyps has been controversial in the literature. The objective of the study is to detect serum and tissue levels of IL-25 and IL-33 in patients with (CRSwNP) or without (CRSsNP) nasal polyps using enzyme-linked immunosorbent assay (ELISA). Study group consisted of 20 CRSwNP and 20 CRSsNP patients. Control group comprised of 20 volunteers who had been operated with septum deviation without any additional sinonasal pathology, allergy, systemic disease, or medication use. All groups preoperatively underwent paranasal CT examinations and sinonasal pathologies were recorded based on Lund-Mackay radiological staging system. IL-25 and IL-33 levels in serum and tissue samples were analyzed using the ELISA method. Serum IL-25 and IL-33 levels in CRSsNP, CRSwNP, and control groups did not differ statistically significantly (p = 0.345 and p = 0.338). Any statistically significant difference was not detected in mean tissue IL-25 levels among CRSsNP, CRSwNP, and control groups (p = 0.698). Mean tissue IL-33 level in the CRSwNP group was statistically significantly lower when compared with those of CRSsNP and control groups (p < 0.001 and p < 0.001, respectively). A statistically significant negative correlation was detected between tissue IL-33 levels and Lund-Mackay CT scores (r = -0.436 and p = 0.005). In the present study, we conceivably contributed to scarce number of studies conducted on this issue and we think that further studies will better clarify the role of IL-25 and IL-33 in the development of nasal polyps.