Seasonal allergic rhinitis affects sinonasal microbiota

Area of Science:

• Immunology
• Microbiology
• Otolaryngology

Background:

• Allergens and microbes can trigger nasal inflammation, potentially leading to acute bacterial rhinosinusitis (ABRS).
• The impact of allergen exposure on the sinonasal microbiome remains unclear.

Purpose of the Study:

• To investigate whether allergen exposure alters the sinonasal microbiome in individuals with seasonal allergic rhinitis (SAR).

Main Methods:

• A parallel observational study compared healthy adults with SAR (n=20) to nonallergic subjects (n=19).
• Sinonasal microbiota specimens were collected via endoscopy from the middle meatus and vestibule.
• Bacterial diversity was analyzed using terminal restriction fragment length polymorphism (T-RFLP) and ecological measures.

Main Results:

• SAR subjects reported increased nasal symptoms, impaired quality of life, and higher nasal eosinophils during the relevant season.
• SAR subjects exhibited significantly greater bacterial diversity in the middle meatus compared to nonallergic subjects.
• A positive correlation was observed between middle meatus bacterial diversity and nasal eosinophil counts in SAR subjects.

Conclusions:

• Allergen exposure significantly alters the sinonasal microbiome composition and diversity in individuals with SAR.
• The interaction between allergic inflammation and the sinonasal microbiome may influence sinonasal physiology.
• Understanding these interactions could elucidate the predisposition to ABRS in allergic individuals.