Characterization of nasal microbiota in pediatric patients with adenoid hypertrophy and allergic rhinitis.

The human nasal cavity hosts a complex bacterial community that is mainly stable at the genus level but can vary between individuals and with the season. Several researchers have shown evidence for dysbiosis of the nasal microbiome in the context of allergic and inflammatory diseases of the airways. However, there are no studies regarding allergic rhinitis (AR) and adenoid hypertrophy (AH), that are common in children and are often associated with each other. AR is a nasal allergic disease characterized by nasal hyper responsiveness, immunoglobulin E (IgE) production, skewing of mucosal immune homeostasis toward a TH2-type response, and accumulation of eosinophils and mast cells. AH is the unusual enlargement of the adenoid tonsil, as a consequence of antigenic stimulation associated with chronic inflammation. Both of them may exist simultaneously and may cause similar clinical symptoms, mainly as nasal obstruction and snoring. This study was aimed to identify the community structure, composition, and functional potential of the commensal microbiota in the anterior nares of 75 pediatric subjects suffering with AR, AH or both, by 16s rDNA gene sequencing