Allergic Conjunctivitis Research Paper

Allergic conjunctivitis

Description

Allergic conjunctivitis is inflammation of the conjunctiva caused due to allergy. It is mainly caused by air borne allergy contacting the eye. Specific IgE causes local mast cell degranulation and the release of chemical mediators including histamines, eosinophil, chemo- tactic factors and platelet activating factors that lead to inflammation. Allergic conjunctivitis occurs more frequently among those with allergic conditions, with the symptoms having a seasonal correlation. It is a frequent condition affecting 20% of the population annually worldwide.

Allergic conjunctivitis may manifest itself in the following forms

1. Hay fever conjunctivitis: It is a recurrent, bilateral type I, IgE mediated hypersensitivity

Phlyctenular keratoconjunctivitis: It is characterized by presence of red nodule at bulbar conjunctiva, most often at nasal limbus of one eye. It is a cell mediated type (type IV) conjunctival hypersensitivity to tubercular protein; the most common endogenous allergen, and others including staphylococcal antigens, worm infestations, fungal antigens, idiopathic hypersensitivity reaction of the cornea and conjunctiva. It is characterized by discrete nodular areas of corneal or conjunctival inflammation.

6. Conjunctivitis medicamentosa: Also known as toxicogenic conjunctivitis is caused by medicine or toxin instilled into the conjunctival sac.

Causes and transmission

The cause of allergic conjunctivitis is an allergic reaction of the body's immune system to an allergen. Allergic conjunctivitis is common in people who have other signs of allergic disease such as hay fever, asthma and eczema. Organisms like Staphylococcus aureus, Mycobacterium tuberculosis, Chlamydia sp. Candida albicans and parasites (Ascaris lumbricoides, Ancylostoma duodenale) are the main causative agent of Phlyctenular keratoconjunctivitis. Allergic disorders are not contagious and hence this type of conjunctivitis is usually not transmitted by contact.

The most common allergens that cause conjunctivitis are:

• Pollen from trees, grass and ragweed

• Animal skin and secretions such as

An allergy skin test to identify specific allergen.

2. A blood test to determine the level of antibodies produced, eosinophil count and total WBC count

PRECAUTION & PREVENTION

Preventive methods include

1. Avoiding allergic triggers.

2. Practicing personal hygiene.

3. Washing hands after using the toilet

4. Avoiding rubbing of eyes in case of irritation as much as possible

5. Those who wear contact lenses should be instructed to discontinue lens wear until signs and symptoms are resolved

6. Infected patients should be advised to stay home from school and work.

Treatment

The following treatment is effective in treatment of allergic conjunctivitis

1. Topical combination of antihistamine (Antazoline 0.5% or Pheniramine) and vasoconstrictor (Naphazoline hydrochloride 0.05%) eyedrops 4 times a day till the resolution of symptoms.

2. Disodium cromoglycate 4% eyedrops 2 times a day or 2% eyedrops 4 times a day till resolution of symptoms.

3. Ketorolac tromethamine 0.5% eyedrops 4 times a day till resolution of symptoms.

4. Tab. Cetirizine hydrochloride 10mg once a day for duration of acute symptoms

5. Topical steroid-dexamethasone or betamethasone

6. Antibiotic drops and ointment in case of allergy caused due to bacterial