What Is Pink Eye? Causes, Symptoms, and Treatment
Summertime is all about fun in the sun. Trips to the beach and dips in the pool become commonplace for kids on summer vacation. Unfortunately, this fun can be a breeding ground for pink eye, which really isn't well... fun.
Pink eye—also known as viral, allergic, or bacterial conjunctivitis—comes from a number of different sources. Viral conjunctivitis is the most common and most contagious form of the disease, with bacterial conjunctivitis a close second. Allergic conjunctivitis isn't contagious, but during the summer months, it's just as prevalent as the viral version.
This form of conjunctivitis is caused by an adenovirus. These types of viruses need host cells that originated as epithelial cells and this makes the eye a prime target. There are three types of conjunctivitis in the viral group.
The first is pharyngoconjunctival fever (PCF) which is caused by adenoviruses that typically affect the respiratory system. It is typically contracted in swimming pools (hence its nickname “swimming pool conjunctivitis”).
The second type of viral conjunctivitis is more serious and more contagious. It is called epidemic keratoconjunctivitis and occurs mainly in adults.
Since adenoviruses can remain active for weeks, usually on sinks, hand towels and doorknobs, this conjunctivitis is easily transmitted.
It typically begins with a sore throat prior to the ocular manifestation of symptoms and can end with corneal involvement that may leave permanent scarring.
The third and most painful form is the herpes virus. It is a common form of conjunctivitis, and almost always involves the cornea. Herpes keratoconjunctivitis is extremely painful causing light sensitivity, foreign body sensations, and sharp shooting pains. If caught early, damage to the cornea may be limited, or avoided.
There are a couple of different bacteria that cause this form of conjunctivitis. The most common is staphylococcus aureus, the same bacteria that also causes boils, impetigo and other skin infections. It is also the same bacterium that causes MRSA or methicillin resistant staphylococcus aureus, although it’s not typically methicillin resistant (but it can be).
Bacterial "Pink Eye"
Gonococcal conjunctivitis is another common form of the disease. Most newborn infants are given an ointment in the lower lid after a vaginal birth, and even C-sections, to prevent this form of conjunctivitis. Like its name suggests, it is a result of the venereal disease gonorrhea. I’m sure you can imagine how it gets to the eye in an adult.
The most common form of bacterial conjunctivitis in children is caused by a pathogen known as Haemophilus influenzae. This bacterium is actually part of the normal flora that resides in our respiratory system, specifically the upper respiratory tract. It is also one of the more common causes of meningitis in children and can occasionally cause upper respiratory infections in both children and adults.
Chlamydial conjunctivitis is typically caused by chlamydia trachomatis and is a leading cause of blindness in the world. It is an epidemic in countries such as North Africa, the Middle East, and South Asia, mainly because of poor hygiene and sanitation. Deficient diets and over-crowding is another cause.
Allergic and Chemical Conjunctivitis
Allergic conjunctivitis, as its name suggests, is caused by an allergen. It can be an ocular allergy, or part of a reaction caused by hay fever. It can sometimes be a reaction to an organism, such as tuberculosis or staphylococcus bacillus, trying to invade the eye.
Allergic "Pink Eye"
Chemical conjunctivitis is most commonly caused by over exposure to chlorine and is typically seen in the summer when kids are out of school. Many industrial workers exposed to chemical fumes may also be affected.
Symptoms and Treatment
Each type of conjunctivitis has its own set of symptoms, which makes it easier to determine which type the patient has, and how to treat it.
Viral conjunctivitis makes the eye look very red, and typically has a very watery discharge. With more severe cases, light sensitivity and pain can occur, especially if the cornea becomes involved like with epidemic or herpetic keratoconjunctivitis.
Antiviral eye drops, such as Viroptic, are usually given, but they don’t always do the trick. Many doctors feel it’s better to let the virus run its course. In the case of herpes keratoconjunctivitis, an oral antiviral, such as acyclovir, is given along with antiviral eye drops.
Bacterial conjunctivitis is the easiest to recognize. The eye is red and has a purulent (mucous) discharge. Sensitivity to light and mild pain, usually in the form of a foreign body sensation, can accompany this form.
Antibiotics are usually given, and depending on which bacteria your doctor suspects, cultures may be taken and sent to a lab. Treatment may change once results are received.
Allergic conjunctivitis is the easiest to treat. Normally, the symptoms are similar to that of any allergy: itching, tearing, and burning. Sometimes a foreign body sensation is present, but it’s not very common.
Treatment involves either removal of the allergen (if known) or antihistamine eye drops such as Elestat, or Pataday. Zaditor is an excellent antihistamine and is now available over the counter. Allergy testing can be beneficial in the case of chronic allergic conjunctivitis.
The moral of this story is wash your hands and always use a clean towel! If you’re out and about and do not have access to a sink and soap, make a conscious effort to avoid touching your eyes with your hands no matter how much they itch. Hand sanitizer doesn’t kill everything.
Wash Those Hands!
I hate to have to even bring this up, but make wise choices when it comes to sex. I’ve seen so many patients come in with both Gonococcal and Chlamydial conjunctivitis and it’s just not pretty. Not to mention how embarrassed the patient is to tell us how they actually got the disease into their eye, and I’ve heard some stories! Again, wash your hands before touching your eyes! Herpes can also be transmitted to the eye this way, so washing the hands is extremely important.
© 2012 Melissa Flagg COA OSC