Microbial Association with Adenoid Hypertrophy in Nasal Cavity and Adenoid Tissues

Abstract

Abstract Nasal cavity and Nasopharynx are habitats for both the pathogenic and non-pathogenic bacteria. Adenoid hypertrophy (AH) is the main cause in children, with a high incidence, for the airflow reduction in the upper airways. However, limited research exposed the impact of AH on the nasal microbial compositions. To determine the association between nasal microbiota and AH, total DNAs were collected and extracted from the nasal cavity and the hypertrophic adenoid of the donors, and the 16 S rRNA gene region was sequenced. Microbial diversity was compared between the healthy and AH groups and the enriched functional pathways were predicted. Although the alpha-diversity of microbial communities did not show statistically significant difference between the groups, principal Co-ordinates Analysis (PCoA) revealed that the microbiota component in the nasal cavity as well as in the hypertrophic adenoid tissues of children with AH was significantly different from the healthy children. Genera Alloiococcus, Moraxella, Streptococcus, and Bacteroidesce were specifically enriched in the AH group’s samples, among which, Moraxella spp. was significantly enriched in both nasal cavity and adenoid tissues, indicating a potential association of it with AH. In addition, Tax4fun prediction revealed disordered microbial functions in AH children. Nutrient metabolism, signaling system, chemotactic reaction, genetic replication, and reproduction related pathways all significantly decreased in the AH group, but increased after adenoidectomy treatment. The findings in this study revealed a high association between specific microorganisms and AH disease. Future work is needed to investigate the role of Moraxella spp. in AH development.