CLC and chronic rhinosinusitis with nasal polyps: Charcot–Leyden crystal (CLC), serum amyloid A (SAA), IL-25, and the ratio of 11β-hydroxysteroid dehydrogenase 1/11β-hydroxysteroid dehydrogenase 2 (11β-HSD1/11β-HSD2) have been identified as biomarkers predicting GC response in patients with CRSwNP (Hong et al., 2018; Lu et al., 2018; Jiang et al., 2019; Wu et al., 2019).