Conjunctivitis%20-%20allergic,%20seasonal%20-and-%20perennial Signs and Symptoms
Introduction
- Most common form of allergic conjunctivitis in temperate climates
- Usually occurs & recurs at a certain period of the year (eg summer)
- Subjectively more severe than PAC
Perennial Allergic Conjunctivitis (PAC)
- Manifests & recurs throughout the year with no seasonal predilection
- Most common in tropical climates
Pathophysiology
- Direct exposure of ocular mucosal surfaces to the environment that causes an immediate hypersensitivity reaction in which triggering antigens couple to reaginic antibodies (IgE) on the cell surface of mast cells & basophils, leading to the release of histamines that causes capillary dilation & increased permeability &, thus, conjunctival injection & swelling
- Nerve endings are also stimulated causing pain & itching
- Nerve endings are also stimulated causing pain & itching
Signs and Symptoms
- Ocular/periocular itching with redness, tearing, burning, stinging, photophobia, watery discharge, &/or ecchymosis (“allergic shiner”), foreign body sensation; characterized by exacerbations & remissions
- Itching is considered the cardinal symptom
- Identify the date & timing of onset, & progress of symptoms
- Symptoms tend to decrease with age