Inflammation - conjunctiva; Pink eye
Conjunctivitis is swelling (inflammation) or infection of the membrane lining the eyelids (conjunctiva).
The conjunctiva is exposed to bacteria and other irritants. Tears help protect the conjunctiva by washing away bacteria. Tears also contain enzymes and antibodies that kill bacteria.
There are many causes of conjunctivitis. Viruses are the most common cause. Other causes include:
"Pink eye" refers to a viral infection of the conjunctiva. These infections are especially contagious among children.
Newborns can be infected by bacteria in the birth canal. This condition is called ophthalmia neonatorum, and it must be treated immediately to preserve eyesight.
See also:
Wirbelauer C. Management of the red eye for the primary care. American Journal of Medicine. 2006;119:302-306.
Mueller JB, McStay CM. Ocular infection and inflammation. Emerg Med Clin North Am. 2008.26:57-72.
Rubenstein JB, Jick SL. Disorders of the conjunctiva and limbus. In: Yanoff M, Duker JS, Augsburger JJ, et al, eds. Ophthalmology. 2nd ed. Philadelphia, Pa: Mosby Elsevier; 2004: chap 55.