Inflammatory Endotypes and Microbial Associations in Chronic Rhinosinusitis

Area of Science:

• Immunology
• Microbiology
• Otolaryngology

Background:

• Chronic rhinosinusitis (CRS) is a complex inflammatory condition with poorly understood causes.
• Emerging research suggests CRS can be classified into distinct variants (endotypes) based on inflammatory biomarkers.

Purpose of the Study:

• To analyze inflammatory patterns in CRS phenotypes.
• To identify potential CRS endotypes.
• To investigate associations between inflammation and the sinonasal microbiota.

Main Methods:

• Cytometric bead array and immunohistochemistry were used to assess cytokines and inflammatory cells in CRS subjects and controls.
• Cluster analysis of inflammatory markers and comorbidities (polyposis, asthma, aspirin sensitivity) identified subject clusters.
• Reanalysis of bacterial data explored associations with inflammation and CRS subtypes.

Main Results:

• Inflammatory patterns varied significantly within standard CRS phenotypes.
• Eight subject clusters were identified, primarily delineated by polyposis and asthma, with subtle inflammatory differences.
• Depletion of health-associated bacteria, reduced diversity, and increased bacterial load correlated with inflammation and clinical severity.

Conclusions:

• This study advances the definition of CRS endotypes based on inflammatory processes.
• Evidence strongly links bacterial community dysbiosis to inflammation in CRS.
• Understanding CRS heterogeneity is vital for clinical management and personalized therapies.