Allergic Conjunctivitis: Simple Allergic and Vernal Keratoconjunctivitis
It is the Inflammation of conjunctiva due to allergic or hypersensitivity reactions which may be immediate( humoral) or delayed( cellular). Conjuctiva is highly sensitive to allergens than our skin( upto 10 times). Allergic conjunctivitis is prevalent around the world.
Classification-
- Simple Allergic
- Hay fever Conjuctivitis
- Seasonal Allergic Conjunctivitis
- Perrenial allergic Conjunctivitis
- Vernal Keratoconjunctivitis
- Atopic Keatoconjunctivitis (often associated with atopic dermatitis)
- Giant papillary Conjunctivitis ( Contact lens related)
- Phlyctenular Keratoconjunctitvitis
- Contact Dermoconjunctivitis
We will be discussing details on Simple Allergic conjuctivitis.
SIMPLE ALLERGIC CONJUNCTIVITIS-
It is a milder, non-specific allergic state of conjunctiva, Acute or subacute urticarial reaction, with symptoms like itching, hyperemia ( prominent vessels and redness) and mild papillary response .
Occurs in response to pollens (grass, weed, or tree) . Weed pollens – summer and the beginning of fall, grass – tree pollens -spring and well into the summer.
Sometimes- cosmetics, cigarette smokes,dust and dust mites, fungal spores, and mold can cause perennial problem.
Etiology or Cause-
- Hay fever conjunctivitis- Very commonly occurs in association with allergic rhinitis. Common allergens like pollens, animal dandruff and grass are responsible for this condition.
- Seasonal Allergic Conjunctivitis- Very commonly occurring condition in response to seasonal allergens like pollen grass.
- Perennial Allergic Conjunctivitis- Occurs in response to allergy to house dust and mites that person remains exposed to all the time. It is rarer.
Pathology- Vascular , Cellular and Conjunctival response are responsible for SAC.
Symptoms-
- Intense itching,
- burning in eyes,
- watery discharge and
- mild photophobia ( sensitivity of eye to bright light).
Signs-
- Hyperemia and chemosis: swollen boggy appearance of conjunctiva,
- Edema of lids and mild papillary reaction.
Diagnosis is made from clinical features, normal flora on culture and abundant eosinophils in discharge.
Treatment-
- Allergens – source of dust, mites, pet animals must be avoided.
- Local measures- for immediate relief
Vasocontrictors like adrenaline,ephedrine
Sodium Chromoglycate drops are quite effective
Steroids drops must be AVOIDED.
- Systemic antihistaminics
- Desensitization- may be tried.
Reference- Comprehensive Ophthalmology-A K Khurana, allergyescape.com.
READ ABOUT VERNAL KERATOCONJUCTIVITIS or VKC