Fungi are present in the mucus of chronic rhinosinusitis (CRS) patients and normal healthy controls. Fungi (especially Alternaria) induce the production of cytokines (IL-13 and IL-5) crucial for the eosinophilic inflammation. This immune response occurred only in CRS patients but not in healthy controls. Fungi induce an eosinophilic tissue airway inflammation in mammals (mice), which is in contrast to a neutrophilic response to bacteria. Fungi can induce an eosinophilic airway inflammation and congestion in patients. Eosinophils, in vivo, target fungi in the mucus with CRS and nasal polyps. Fungal antigens with a molecular weight of 61 kilodaltons (kDa) cause activation and degranulation of human eosinophils via the beta-2 integrin on the CD11b receptor. Clinically, antifungal drugs can reduce nasal polyps, improve computed tomography (CT) scans, and decrease levels of interleukin-5 (IL-5) and markers of eosinophilic inflammation. However, data between different antifungal applications and different outcome measures are conflicting.
ASJC Scopus subject areas