“Pink eye” is a nonspecific term commonly used to describe a red or inflamed eye. The medical term for pink eye is conjunctivitis. Conjunctivitis means inflammation of the conjunctiva, the mucous membrane that covers part of the surface of the eye and also lines the inside surface of the eyelids. Pink eye is a common patient concern. There are several types of conjunctivitis and not all of them require antibiotic treatment.
The usual causes of conjunctivitis can be categorized as infectious and non-infectious. Infectious conjunctivitis can be subdivided into bacterial and viral. Non-infectious causes include allergic and non-allergic.
Bacterial conjunctivitis is highly contagious and is easily spread by coming in direct contact with the infected person’s eye secretions or by contacting objects that have been contaminated by the secretions. A typical case involves redness and thick discharge from one eye, although both eyes may be involved. The discharge continues to drain throughout the day and can be green, yellow or white. The affected eye can be “stuck shut” in the morning, but this can also occur with other forms of conjunctivitis. Bacterial conjunctivitis does require antibiotic treatment with either eye drops or ointment and fortunately it responds quickly to treatment. People are generally considered to be contagious until they have received greater than 24 hours of appropriate treatment.
Viral conjunctivitis is due to a virus and is often associated with symptoms of the common cold. This too, like bacterial conjunctivitis, is contagious, but it does not require treatment. This is self-limited and generally lasts just a few days. This pink eye often has eye redness, a gritty sensation and watery or mucous discharge. It often spreads from one eye to the other over a course of 24-48 hours. The eye may be “stuck shut” after sleeping but typically the discharge does not persist through the day like it does with bacterial conjunctivitis.
Allergic conjunctivitis is due to airborne allergens coming in contact with the eye and triggering an allergic response. Typically both eyes are equally involved and there is redness, watery discharge and itching. Itching is the classic symptom that distinguishes this type of conjunctivitis from other causes. Allergic conjunctivitis is often associated with other forms of atopic diseases such as eczema, asthma, seasonal allergies or environmental allergies. Treatment entails suppressing the allergic response with the use of allergy eye drops or other allergy medications.
The last broad category of conjunctivitis is non-infection, non-allergic conjunctivitis. This is a red eye with discharge that is not related to an infectious or inflammatory process. Such causes include: eye dryness, chemical irritation or ocular foreign bodies. Each of these entities have their own specific treatment.
Finally, some other causes of a red eye are much less common but can be much more concerning. Warning signs for these types of serious causes include:
- Reduction in visual acuity
- A pattern of eye redness that is concentrated immediately around the iris (colored part of the eye).
- Trouble viewing light
- A severe foreign body sensation
- Opacity of the cornea (area overlying the pupil and iris)
- A fixed pupil
- Severe headache associated with nausea
These types of eye concerns would be best cared for by an eye specialist. It is important to identify the true causes of pink eye before the appropriate treatment can be rendered. Hopefully this brief description of the general categories of pink eye can help you understand what treatment, if any, is required for each of the specific types of pink eye.
By Dr. Luke Tremble, pediatrician, ThedaCare Physicians-Pediatrics in Appleton.