Differential NF-κB mRNA Expression in Blood and Buccal Mucosa of Pediatric Patients with RSV Bronchiolitis

Background: Respiratory syncytial virus (RSV) bronchiolitis is a leading cause of lower respiratory tract infections in children under two years of age. NF-κB is a key transcription factor in antiviral and inflammatory responses. This study investigates the expression of NF-κB mRNA in both blood and buccal swab samples of pediatric patients hospitalized for RSV bronchiolitis, comparing levels at admission and discharge. Methods: Paired peripheral blood and buccal swab samples were collected from pediatric patients (n = 85) at hospital admission and discharge. Quantitative real-time PCR was used to assess NF-κB mRNA levels. Results: NF-κB mRNA levels significantly decreased in blood between admission and discharge (p < 0.05), while no significant change was observed in buccal swabs. Conclusions: These results suggest a compartment-specific regulation of NF-κB, with systemic inflammatory resolution at discharge and persistent or distinct mucosal immune activity. Understanding these dynamics may improve our approach to monitoring and treating RSV bronchiolitis.