Classification of non-allergic rhinitis based on inflammatory characteristics

Area of Science:

• Immunology
• Respiratory Medicine
• Otorhinolaryngology

Background:

• Non-allergic rhinitis (NAR) presents diagnostic challenges.
• Understanding the inflammatory profile of NAR is crucial for effective management.
• NAR may involve systemic inflammatory processes affecting both upper and lower airways.

Purpose of the Study:

• To investigate nasal and lower airway inflammation in non-allergic rhinitis (NAR) patients.
• To develop a classification system for NAR based on inflammatory characteristics.
• To assess the clinical significance of this proposed NAR classification.

Main Methods:

• Recruited 117 NAR patients and 162 healthy controls.
• Evaluated inflammation via skin prick tests, visual analogue scales, blood counts, nasal douche, induced sputum assays, and nasal/bronchial provocation tests.
• Correlated inflammatory markers and provocation test results.

Main Results:

• NAR patients showed significantly higher eosinophil levels (nasal douche, sputum, blood) and provocation test rates than controls.
• Elevated nasal eosinophils correlated with higher sputum eosinophils.
• Nasal and bronchial provocation test scores were also correlated.

Conclusions:

• NAR patients demonstrate distinct inflammatory patterns and airway hyper-reactivity.
• A proposed classification categorizes NAR into non-specific, eosinophilic, and hyper-reactive types.
• NAR can be viewed as a systemic inflammatory disease involving nasal eosinophilia and hyper-reactivity.