Viral Detection and Clinical Disease Features in Pediatric Chronic Rhinosinusitis

Objectives Chronic rhinosinusitis (CRS) results from complex host‐environment interactions with microbiome dysbiosis and viral infections postulated to drive inflammation and anatomic remodeling. This study investigates the impact of viral presence on pediatric sinonasal disease and clinical outcomes. Methods A prospective, case–control study with retrospective data collection was conducted at a single‐institution tertiary children's hospital. Pediatric patients undergoing sinus surgery for CRS (cystic fibrosis [CF] and non‐CF CRS groups) and a control group undergoing structural septoplasty were enrolled from 2018–2022. Sinus swabs were collected intraoperatively and during up to 3 years of follow‐up. A 14‐virus panel was run. 16S and custom amplicon sequencing and quantitative PCR assessed microbial profiles. Clinical and endoscopic data were recorded. Results Sinonasal swabs were collected from 15 CF‐CRS, 21 non‐CF CRS, and 32 control patients during initial sinus surgery. At least one virus was detected in 30.9% of samples ( n = 21/68): 18.8% ( n = 6/32) in controls, 33.3% ( n = 7/21) in non‐CF, and 53.3% ( n = 8/15) in CF. Human rhinovirus (HRV) was most common, comprising 45.8% ( n = 11/24) of viral detections. Across study duration, viral‐positive CRS individuals were 3.49 times more likely to report nasal drainage (95% CI: 1.59–9.25, p = 0.005) and 4.23 times more likely to exhibit discharge on endoscopy (95% CI: 1.40–12.81, p = 0.011) than viral‐negative individuals. HRV‐positive samples had decreased Corynebacterium prevalence ( p = 0.025), increased Haemophilus prevalence ( p = 0.052), and increased Pseudomonas relative abundance ( p = 0.076) versus viral‐negative samples. Conclusion Viral infections can exacerbate pediatric CRS by increasing nasal drainage and endoscopic discharge while promoting chronic inflammation and persistent disease.