Potential Differences between Local and Systemic Allergic Rhinitis Induced by Birch Pollen.

Area of Science:

• Immunology
• Allergology
• Otolaryngology

Background:

• Rhinitis presents with various endotypes, yet its precise pathomechanisms remain unclear.
• Distinguishing between systemic allergic rhinitis (SAR) and local allergic rhinitis (LAR) requires further investigation.

Purpose of the Study:

• To compare the immunological differences between patients with LAR, SAR (birch allergy), and non-allergic rhinitis (NAR).

Main Methods:

• Included 26 LAR, 18 SAR (birch allergy), and 21 NAR patients.
• Performed medical examinations, nasal provocation tests (NPT), and measured nasal-specific IgE and basophil activation tests (BAT) to birch (Bet v1) before and after NPT.

Main Results:

• Nasal IgE to Bet v1 increased post-NPT in 81% of LAR and 78% of SAR patients.
• Serum IgE to Bet v1 significantly increased post-NPT only in SAR patients.
• Basophil activation tests (BAT) with Bet v1 were positive in 85% of LAR and 78% of SAR patients, but only 9.5% of NAR patients.

Conclusions:

• The study found no distinct immunological mechanisms to differentiate LAR from SAR in birch-allergic individuals.
• Current data do not support unique pathomechanisms for LAR compared to SAR.