Allergic diseases of the eye

• Allergic conjunctivitis involves an inflammatory reaction predominantly occurring in the conjunctiva
• The conjunctiva is the most obviously exposed mucous membrane in the body and is very accessible to allergens
• Most common forms of allergic conjunctivitis are IgE-mediated and may be associated with rhinitis and asthma
• Subsets of ocular allergy include Simple Allergic Conjunctivitis, Vernal Keratoconjunctivitis (VKC), Atopic Keratoconjunctivitis (AKC), and Giant Papillary Conjunctivitis
• Symptoms of ocular allergy include itching, conjunctival hyperemia, tearing, conjunctival edema/chemosis, mucous discharge, eyelid edema, photophobia, eye rubbing, and blurred vision
• Acute Allergic Conjunctivitis presents with sudden onset redness and swelling of the conjunctiva, significant lacrimation, and usually settles within 24 hours
• Seasonal Allergic Conjunctivitis (SAC) is also known as "hay fever conjunctivitis" and is usually combined with rhino-conjunctivitis
• Perennial Allergic Conjunctivitis (PAC) has persistent symptoms year-round with seasonal exacerbations, often triggered by animal dander, house-dust mite, and molds
• Vernal Keratoconjunctivitis (VKC) is a sight-threatening, bilateral, and chronic disease that occurs in children and young adults, more common in hot, dry windy climates
• Atopic Keratoconjunctivitis (AKC) is seen in older patients and is associated with severe constitutional atopic disease and atopic dermatitis
• Giant Papillary Conjunctivitis (GPC) is a non-infectious inflammatory disorder of the superior tarsal conjunctiva, often associated with contact lenses
• Treatment options for allergic eye disease include avoidance of allergens, systemic antihistamines, topical antihistamines and vasoconstrictors, mast cell stabilizers, NSAID drops, topical corticosteroids, immunosuppression, and immunotherapy
• Complications of allergic conjunctivitis are rare but can include scarring of the eye and secondary infective conjunctivitis