IL13 and chronic rhinosinusitis without nasal polyps: Dexamethasone and clarithromycin could significantly inhibit the protein production of IL-5 (Fig. 8c) and IL-13 (Fig. 8f) in only eosinophilic polyp tissues, possibly due to the very low expression levels of IL-5 and IL-13 in CRSsNP and non-eosinophilic CRSwNP.