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

Abstract

Introduction: Different endotypes of rhinitis are known, but its pathomechanism has not been conclusively established. For example, the precise difference between systemic allergic rhinitis (SAR) and local allergic rhinitis (LAR) is still being checked. Comparison of patients with LAR and with allergies to birch of those with intermittent allergic rhinitis, same allergy, or with non-allergic rhinitis (NAR) was the purpose of this study. Methods: Twenty-six patients with LAR, 18 with SAR and allergy to birch, and 21 with NAR were included. Patients who met the inclusion criteria were selected to undergo the following procedures at baseline: medical examinations, nasal provocation test (NPT), detection of nasal-specific IgE to birch as well as basophil activation test (BAT). All immunological parameters were detected before and after NPT. Results: Concentration of nasal IgE to Bet v1 increased comparably in the LAR and SAR groups after NPT to birch as follows: in 21 (81%) patients with LAR, 14 (78%) with SAR, and in everyone in the NAR group. Serum concentration of allergen-specific IgE to Bet v1 increased significantly from a median of 20.7 (25–75% interval: 11.2–35.6) IU/mL to 29.9 (13.6–44.1) (p = 0.028) after NPT in patients with SAR. Allergen-specific IgE to Bet v1 was absent in all patients with LAR and NAR before and after NPT. BAT with Bet v1 was positive in 22 (85%) patients with LAR, in 14 (78%) with SAR, and 2 (9.5%) with NAR. Conclusion: These obtained data suggest there are no potential mechanisms that could explain LAR compared to SAR.