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Conjunctival effects of a selective nasal pollen provocation
I Callebaut1, L Spielberg, V Hox
1University Hospitals Leuven, Catholic University Leuven, Leuven Belgium.
Allergy
|April 27, 2010
Summary
Nasal allergen exposure triggers eye symptoms in allergic rhinitis, demonstrating a naso-ocular connection. This study highlights objective methods for assessing conjunctival inflammation in allergic rhinoconjunctivitis.
Area of Science:
- Allergy and Immunology
- Ophthalmology
- Otorhinolaryngology
Background:
- Clinical observations suggest nasal allergen deposition contributes to conjunctival symptoms in allergic rhinitis.
- The study aimed to investigate this naso-ocular link through controlled nasal allergen provocation.
Purpose of the Study:
- To evaluate the induction of conjunctival symptoms via selective nasal allergen provocation.
- To assess objective tools for measuring allergic conjunctival inflammation.
Main Methods:
- 12 subjects with allergic rhinoconjunctivitis underwent nasal grass pollen provocation.
- Nasal and conjunctival symptoms, Peak Nasal Inspiratory flow (PNIF), and tear fluid markers (histamine, substance P) were measured.
- Visual Analogue Scale (VAS) and tear fluid analysis were employed.
Main Results:
- Nasal grass pollen provocation induced ocular pruritus, lacrimation, and conjunctival vascular congestion.
- Tear histamine and substance P levels correlated with conjunctival symptoms.
- PNIF values showed an inverse correlation with lacrimation and ocular pruritus.
Conclusions:
- Selective nasal allergen provocation effectively induces conjunctival inflammation and symptoms.
- A significant naso-ocular interaction exists in allergic rhinitis.
- Objective tools like tear fluid analysis and PNIF measurements are valuable for evaluating conjunctival inflammation.
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