The Role of the Adenoid in Facilitating Biofilm Infection in the Upper Respiratory Tract

ABSTRACT: This narrative review evaluates the role of the adenoid as a reservoir for bacterial biofilms contributing to persistent upper respiratory tract infections. A total of 24 studies were screened, and 14 primary research articles were included. The prevalence of adenoid biofilm in pediatric populations ranged from 21.2% to 100%, with the highest presence near the Eustachian tube. Most common pathogens identified were Staphylococcus aureus, Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis. The studies consistently report an association between biofilm presence and recurrent or chronic otitis media, chronic rhinosinusitis, and upper airway infections. Detection methods included scanning electron microscopy, spectrophotometry, and fluorescence in situ hybridization, with variable reporting of biofilm quantification and pathogen identification. Biofilm formation correlates with antibiotic resistance and the chronicity of infections. Clinical evidence supports adenoidectomy as an effective intervention to reduce recurrent infections. However, limitations include observational study designs and heterogeneity in detection methodologies, limiting causal inferences. The review emphasizes the need for standardized detection methods and robust clinical trials to evaluate novel antibiofilm therapies. These findings underscore the importance of recognizing the adenoid’s role in persistent infections and guiding appropriate clinical management. Keywords: Adenoid, Biofilm, Upper Respiratory Tract Infections, Otitis Media, Adenoidectomy, Bacterial Reservoir, Staphylococcus aureus, Haemophilus influenzae