Nasal Microbial Community Shifts Following Treatment in Chronic Rhinitis: An Observational Study

Objectives: Nasal microbiome helps maintain mucosal homeostasis and immune function. Previous studies suggested the pathogenesis of chronic rhinitis and the nasal microbiome were related. This study aimed to evaluate the treatment effect on the nasal microbiome in chronic rhinitis through analyzing microbial diversity and composition in pre- and post-treatment status. Methods: In participants diagnosed with chronic rhinitis, nasal microbiome samples were collected before and after treatment. Treatment regimens included intranasal corticosteroid spray, oral antihistamines, and/or oral leukotriene receptor antagonists. The degree of symptom improvement was measured by rhinitis symptom questionnaires assessing four nasal symptoms, two ocular symptoms, and quality of life (QOL). Laboratory tests were performed at baseline, including serum total immunoglobulin E, blood eosinophil percentage, and skin prick test. Results: A total of 22 patients were enrolled. Total nasal symptom score (TNSS), TNSS eye (TNSS with two ocular symptoms), and QOL questionnaire scores all significantly decreased after treatment (p < 0.001). Alpha diversity showed no significant changes, while intra-group distances were significantly decreased for both unweighted and weighted distances after treatment (p < 0.05). The relative abundance of Staphylococcus increased, while that of Alloprevotella decreased after treatment (p < 0.05). Predominant genera in most subjects were Staphylococcus, Acinetobacter, and Burkholderiaceae, and all significantly correlated to QOL improvement after treatment (p < 0.05). Conclusions: This study investigated the impact of chronic rhinitis treatment on the nasal microbiome and its association with symptom improvement. The changes in the nasal microbiome following treatment may enhance our understanding of its role in chronic rhinitis pathophysiology and therapeutic response. Level of Evidence: 3.