2.1 Patient and sample grouping
Twenty-five children diagnosed with rhinosinusitis and requiring endoscopic sinus surgery were included in this study from January 2021 to December 2021 in the Department of Otolaryngology Head and Neck Surgery at our hospital. According to EPOS 2020, 8 patients were diagnosed with ABRS with orbital complications, and 17 were diagnosed with Chronic Rhinosinusitis with Nasal Polyps (CRSwNP). None of the patients had CF, congenital disease, or paranasal sinus masses. The children with ABRS were treated with anti-infection and comprehensive therapy before operation, but their symptoms did not improve significantly. The CRS patients received regular drug treatment in the outpatient department for 3 months, but their symptoms did not improve significantly. All the children were admitted to hospital for endoscopic sinus surgery and nasal secretions were collected for bacterial culture during surgery, and whole blood, nasal mucosa and polyp samples were collected for follow-up experiments. Whole blood samples were collected from parents of some children. All patients’ guardians denied that they had CF-related diseases or had relatives diagnosed as CF in their families.