POSTN and chronic rhinosinusitis with nasal polyps: The following respective mean serum IL-5, POSTN, and IL-33 levels were identified in CRSwNP patients—52.10 pg/mL, 95.04 ng/ml and 69.14 pg/ml; with regards to the control group, the corresponding values were: 14.53 pg/mL, 23.26 ng/ml and 15.43 pg/mL.