IFNG and chronic rhinosinusitis without nasal polyps: After treatment with dexamethasone or clarithromycin, we detected a remarkable and similar decrease of interferon (IFN)-γ protein production (Fig. 8b) from sinonasal mucosa from all CRS groups and IL-12 protein production (Fig. 8e) from sinonasal mucosa from CRSsNP and eosinophilic CRSwNP.