Allergen-specific conjunctival challenge in children with allergic asthma: a clinical tool

Les tests de provocation conjonctivaux

The conjunctival provocation test (CPT) is a human model of ocular allergy that has been used to study the ocular response to allergenic stimuli and to evaluate antiallergic therapy. Considerable useful information has been gained on the ocular allergic response and drug efficacy using the conjunctival provocation test and naturally occurring seasonal allergic conjunctivitis. The safety and the efficacy of these CPTs has resulted in many authors using this tool in the etiologic diagnosis of allergic conjunctivitis. This article summarizes the possibilities of these CPTs as a tool for the study, evaluation, diagnosis, and therapeutic follow-up of allergic conjunctivitis.

Rapid anti-inflammatory action of azelastine eyedrops for ongoing allergic reactions

BACKGROUND

Some second-generation antihistamines have anti-inflammatory activities, but the clinical relevance of this property is still unclear.

OBJECTIVE

The aim of our study was to investigate the effects of azelastine when administered during the early-phase reaction.

METHODS

This investigation was designed as a randomized, placebo-controlled, double-blind, parallel-group study. Clinical and inflammatory events were evaluated after a single dose of azelastine eyedrops or placebo was administered 30 minutes after an allergen-specific conjunctival challenge. Twenty outpatients with allergic rhinoconjunctivitis attributable to Parietaria judaica were enrolled in the study outside the pollen season. Patients were evaluated at baseline, after allergen challenge (at 30 minutes), and after administration of azelastine (at 30 minutes and at 6 hours). The following variables were evaluated: hyperemia, lacrimation, itching, eyelid swelling, number of inflammatory cells (neutrophils, eosinophils, monocytes, and lymphocytes), and intercellular adhesion molecule-1 expression on conjunctival epithelial cells.

RESULTS

Azelastine, in comparison to placebo, significantly reduced symptom scores, number of inflammatory cells, and intercellular adhesion molecule-1 expression during the early- and late-phase reaction.

CONCLUSIONS

The ability of azelastine to reduce symptoms and inflammation during an ongoing allergic reaction can be considered concrete and convincing proof of a clinically relevant anti-inflammatory activity.