Olfactory dysfunction in seasonal and perennial allergic rhinitis

Area of Science:

• Otorhinolaryngology
• Immunology
• Allergy

Background:

• Olfactory dysfunction is common in allergic rhinitis (AR).
• The specific mechanisms driving smell impairment in AR remain unclear.
• Understanding these mechanisms is crucial for effective treatment strategies.

Purpose of the Study:

• To investigate olfactory function in patients with seasonal or perennial AR.
• To correlate olfactory performance with nasal secretion markers and obstruction levels.
• To elucidate the pathophysiological basis of smell loss in AR.

Main Methods:

• Olfactory function assessed using the Sniffin' Sticks test.
• Nasal secretions analyzed for eosinophilic cationic protein (ECP) and tryptase.
• Nasal obstruction evaluated via rhinomanometry.
• Comparison between AR patients (seasonal/perennial) and a healthy control group.

Main Results:

• Patients with AR demonstrated significantly reduced olfactory function compared to controls.
• Elevated ECP and tryptase levels were observed in the nasal secretions of patients with seasonal AR.
• Rhinomanometry revealed no significant differences in nasal airflow between AR patients and controls.

Conclusions:

• Impaired olfactory function in AR is primarily linked to heightened eosinophilic and mast cell activity within the olfactory cleft.
• Epithelial inflammation, rather than nasal obstruction, is the main driver of olfactory deficits in AR.
• Targeting inflammatory pathways in the olfactory cleft may improve smell function in AR patients.