Definition The conjunctiva is the clear mucous membrane layer covering the white portion of the eye. It extends under the eyelid where it turns back and becomes the underneath mucous membrane lining of the upper and lower lids. When this membrane becomes inflamed, it is called conjunctivitis.
What are the signs and symptoms of the infection? Symptoms can include:
sore and inflamed eyes
red eyes
puffy eyes
itchy eyes
discharge from the eyes
increased tearing
sensitivity to light
What are the causes and risks of the infection? Causes can include:
bacterial, viral and fungal infections
allergies
foreign matter that gets under the eyelid
chemicals or fumes
What can be done to prevent the infection? The best way to prevent conjunctivitis is to:
practice good lid hygiene, by rubbing the eyelids without soap under the water stream when showering.
keep foreign matter out of the eyes. Individuals should use safety glasses during work or hobbies in which debris is flying around in the air.
How is the infection diagnosed? Doctors diagnose conjunctivitis based on the person's symptoms and by looking at the eye using a slit-lamp microscope, which is a special instrument that magnifies the surface of the eye. Depending on these findings, the cause can usually be determined. For instance, a coloured discharge from the eye usually indicates a bacterial infection. But, when itching and tearing are the main symptoms, allergies are the most likely cause. With viral conjunctivitis there is usually no discharge, but there may be redness and tearing along with formation of follicles under the eyelids.
What are the long-term effects of the infection? It is important to treat the inflammation. If this is not done, symptoms could linger or spread to other parts of the eye or orbit, which is the cup-like hole in the skull that holds the eyeball. If the cornea becomes infected or inflammation spreads to the eyelids, more serious problems such as cellulitis could occur. Cellulitis is an infection that can lead to abscesses, or collection of pus in the tissue, and tissue destruction.
What are the risks to others? If this condition is caused by an infection, then strict hand washing is important. Persons should avoid sharing makeup, towels, linens, or toys to prevent the spread of the condition.
What are the treatments for the infection? Treatment includes:
topical antibiotic medications such as chloromycetin or tobramycin, if conjunctivitis is caused by a bacterial infection
removal of foreign matter from under the lids if this has caused the inflammation
topical drops containing antihistamines, such as levocabastine, non-steroidal anti-inflammatory agents, such as ketorolac, and corticosteroids, such as hydrocortisone or fluorometholone, if allergies are the cause
oral antibiotics if topical antibiotics alone do not solve the problem or if the inflammation seems to be spreading through the eyelid
Author: William Stevens, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
