Conjunctivitis is an inflammation of the conjunctiva (the outermost layer of the eye that covers the sclera), often due to infection. There are three common varieties of conjunctivitis, viral, allergic, and bacterial. Viral and bacterial conjunctivitis are contagious. Other causes of conjunctivitis include toxic conjunctivitis (chemicals), overuse of contact lenses and foreign bodies.
Blepharoconjunctivitis is the combination of conjunctivitis with eyelid inflammation.
Viral conjunctivitis, commonly known as pink eye, is often associated with an infection of the upper respiratory tract, a cold, or a sore throat. Its symptoms include watery discharge and the fact that the infection usually begins with one eye, but may spread easily to the fellow eye.
Allergic conjunctivitis type occurs more frequently among those with allergic conditions, with the symptoms having a seasonal correlation. Allergic conjunctivitis can also be caused by allergies to substances such as cosmetics, perfume, or drugs. It usually affects both eyes, and is accompanied by swollen eyelids.
Bacterial conjunctivitis is often caused by bacteria such as staphylococcus and streptococcus, and the severity of the infection depends on the type of bacteria involved. Bacterial conjunctivitis causes a stringy discharge called gowl that may cause the lids to stick together, especially after sleeping, and irritation and/or a gritty feeling in the eye. Bacterial conjunctivitis can be transferred through infected eye makeup and facial lotions.
Like viral conjunctivitis, it usually affects only one eye but may spread easily to the other eye.
Redness, itching, irritation and watering of the eyes are symptoms common to all forms of conjunctivitis. The presence of a discharge and the consistency thereof may suggest the infectious agent involved (bacterial or viral). A purulent discharge strongly suggests a bacterial infection or a bacterial superinfection. Infection with Neiserria gonorrhea should be suspected if the discharge is particularly thick, copious and purulent.
Other symptoms including pain, blurring of vision and photophobia should not be prominent in conjunctivitis. If these symptoms are present or worse, prominent, a different diagnosis should be suspected so as not to miss other important diseases such as glaucoma, uveitis, keratitis and even meningitis.
The patient should be examined in a well lit room. Injection (redness) of the conjunctiva on one or both eyes should be prominent. A slit lamp should be used to examine the eye if there is suspicion of another disease process or if further magnified examination is necessary.
Occasionally, a swab of the eye is indicated for microscopy and culture to determine the type of bacteria causing the infection.
Conjunctivitis sometimes requires medical attention. The appropriate treatment depends on the cause of the problem. For the allergic type, cool compresses and artificial tears sometimes relieve discomfort in mild cases. In more severe cases, non-steroidal anti-inflammatory medications and antihistamines may be prescribed. Some patients with persistent allergic conjunctivitis may also require topical steroid drops. Bacterial conjunctivitis is usually treated with antibiotic eye drops or ointments that cover a broad range of bacteria.
There is no cure for viral conjunctivitis. However, the symptoms can be relieved with cool compresses and artificial tears. For the worst cases, topical steroid drops may be prescribed to reduce the discomfort from inflammation. Viral conjunctivitis usually resolves within 3 weeks.