A bacterial eye infection can be caused by a number of pathogens. Each will have different symptoms, transmitters and treatments. Fortunately, this type of eye infection is less common than those caused by viruses or allergens. According to the National Eye Institute, some forms resemble pinkeye which is the most commonly reported form in the US with 3 million cases recorded annually. It is diagnosed by an ophthalmologist who can then prescribe the appropriate medications to ensure when it heals it will stay gone. For those not sure if they have a bacterial eye infection or one of the other types of conditions, the following may clarify the types of bacterial infections and when it’s time to see your doctor.
What Is a Bacterial Eye Infection?
A bacterial eye infection can occur in the front, middle and/or back of the eye and can have visually devastating consequences. Each is caused by different organisms and/or pathogens that have different symptoms and require different treatments. Following is information on the top five types.
Acute Bacterial Conjunctivitis
This type of bacterial eye infection is caused by Haemophilus influenzae accounting for 82% of patients, reports staphylococcus pheumoniae in 16% of patients and staphylococcus aureus in 2% of patients. This is down from the number of patients that tested positive for staphylococcus pneumoniae in 1993 because of the institution of pneumococcal conjugate vaccine immunizations.
An eye infection occurs most often between April through November, is most common in infant through pre-school children and is highly contagious. There are 5 million cases in the US annually with one in eight children becoming infected every year. It is a self-limiting disease that usually lasts from 7 to 10 days.
- Inflammation of the conjunctiva.
- Mucopurulent discharge which is a yellowish/green goo resembling pus that mattes on the eyelids.
- Burning eyes.
- Stinging eyes.
The condition usually starts in one eye then spreads to the other. It is transmitted by exposure to the secretions of an infected individual and is treated with a broad-spectrum of topical antibiotics. However, when present in conjunction with otitis media it must be treated with systemic antibiotics. You can tell it from viral conjunctivitis because it is resolved quickly.
Staphylococcus epidermidis and Pseudomonas aeruginosa are the culprits that cause bacterial keratitis. It begins by affecting the outer layer of the cornea, but it can go deeper running the risk of permanent vision impairment. Its rapid progression may be complete within 24-48 hours. It can begin when contact lenses are ill-fitting. It can also occur following cornea surgery or with any other injury that is cornea-related. After acquiring the condition, it tends to get better fairly quickly.
- Eye redness.
- Irritation like sand in the eye.
- Sensitivity to light.
- Watery eyes.
- Blurry vision.
- Difficulty keeping the eyelids open.
- Ulcers on the corneas.
- Corneal scarring.
- Eventual blindness if left untreated.
Individuals contract this form of infection when contact lenses are contaminated by pathogens then slipped into the eyes. Contact lenses should not be worn until the condition is resolved.
The traditional therapy is fortified antibiotics, tobramycin with fortified Cefazolin or vancomycin. Antibiotic eye drops with fluoroquinolones are now frequently used when the traditional therapy is ineffective. Additionally, research has demonstrated that UV irradiation may be necessary to treat corneal ulcers.
As the name implies, this infection targets newborns. It accounts for up to 40% of conjunctivitis cases in babies less than 4 weeks old. It is caused by a bacterial infection from chlamydia trachomatis and neisseria gonorrhea.
The condition results in the swelling or inflammation of the tissue lining the eyelids of a newborn. However, distinguishing between chemical, chlamydial, gonococcai, herpes (which is viral) and other forms of conjunctivitis caused by other bacteria in neonates is extremely difficult. Dependent on causation, the symptoms can develop between 6 hours to 5 days after birth.
- Inflammation of the conjunctiva.
- A mucopurulent discharge within 1 day to 2 weeks after birth.
- Watery, bloody or pus-like drainage from the eyes.
- Puffy, red and tender eyelids.
- Scarring and perforation of the cornea.
- Can cause blindness, inflammation of the iris or a scar or hole in the cornea.
It’s most commonly transmitted from the mother at the time of birth when pathogens attached to the vaginal canal get into the baby’s eyes. For mothers that have chlamydia or gonorrhea, C-sections are often performed rather than taking the risk of exposing the baby to the bacteria. Should a baby be born with the condition, they are frequently treated with erythromycin, ceftriaxone, cefotaxime, polymyxin plus bacitracin erythromycin or tetracycline and/or a system, topical or combined antimicrobial therapy.
In 50% of babies born to mothers with chlamydial ophthalmia, they also develop chlamydial pneumonia. Such infants are treated with erythomycin ethylsuccinate but it only works in 80% of the cases on a first try. It is a macrolide antibiotic that slows the growth, or sometimes even kills, sensitive bacteria by reducing the production of proteins the bacteria need in order to survive. When used on babies it usually comes in the form of a gel.
Additionally, if treated with eythromycin, babies can develop hypertropic pyloric stenosis, which is a gastric outlet obstruction that requires surgical correction. Azithromycin has also been found to effectively treat the condition but is not approved by the American Academy of Pediatrics yet.
For babies born to mothers with gonorrhea, a single dose of ceftriaxone is used along with frequent saline irrigation.
Trachoma (Granular Conjunctivitis)
Trachoma is caused by chlamydia trachomatis and will present as a chronic case of conjunctivitis with trichiasis. The World Health Organization reported in 2015 that 202 million people were visually impaired and 1.2 million were blind as a result of acquiring the disease. It is transmitted through contact with infected individuals or contaminated formites as well as by eye-seeking flies. Early symptoms begin to appear within 5-12 days once infected. Young children are particularly susceptible, but they may not experience severe eye pain until they enter adulthood.
The World Health Organization has identified five stages of development of the condition:
1. Inflammation – follicular. Five or more follicles or small bumps that contain white blood cells can be seen on the inner surface of the upper eyelid.
2. Inflammation – intense. The eye is highly infectious at this point and becomes irritated. A thickening or swelling of the upper eyelid occurs.
3. Eyelid scarring. Infections reoccur often leading to scars developing on the inner eyelid. They look like white lines when examined with magnification. The eyelid may also become distorted and begin turning in.
4. The scarred inner lining of the eyelid continues its deformation. The lashes continue to turn in and begin to rub and scratch the cornea, which is the transparent outer surface of the eye. This condition is called trichiasis.
5. Corneal clouding. The cornea becomes inflamed, especially under the upper lid. The combination of increasing inflammation and scratching of the cornea creates clouding. In addition, the tear-producing glands as well as the lubricating glandular tissue of the lids can also be negatively affected, leading to extreme dryness which aggravates the problem all the more.
- Mild itching.
- Irritation of the eyes and eyelids.
- Discharge from the eyes containing mucus or pus.
- Eyelid swelling.
- Light sensitivity.
- Eye pain.
- Scarring of the cornea.
- Eventual blindness.
This is also a highly contagious condition and treating it as soon as it is identified will help prevent further infections. Treatment includes Azithromycin, however, this medication is not 100% effective. The National Eye Institute has researched the problem and reported that the condition causes blindness in millions of people and largely strikes developing countries. The medication prescribed also protects 50% of treated individuals from other infections bacterial diseases such as pneumonia and malaria.
This type of bacterial eye infection is one of the most common. As reported in a 2009 survey, 37% of patients seeing an ophthalmologist and 47% of those seen by an optometrist were diagnosed with blepharitis. It is caused by staphylococcal aureus, seborrheic associated with dermatitis, meibomian gland dysfunction caused by malfunctioning oil glands in the eyelid or rosacea. In a nutshell, it simply means there is a simple bacterial colonization of the eyelids. It results in a direct microbial invasion of the tissues, immune system, waste products and enzymes.
Blepharitis is a chronic condition and symptoms include:
- Swelling of the eyelid.
- Eye discomfort.
- Scaliness of the skin on the eyelid margins.
- A greasy appearance of the eyelid margins.
- Ulcers on the cornea.
- Crusting and bleeding of the eyelids.
- Stickiness in the eyes.
- Intolerance to wearing contact lenses.
- Excessive watering of the eye or excessive dryness.
- A discharge from the lids.
- Eyelid scarring.
- Sensitivity to light.
- Eyelashes that grow at different angles.
- Frequent blinking.
- Loss of eyelashes.
The condition can also lead to other problems such as cysts, styes, pink eye and injury to the cornea. It is not a sight-threatening problem, but it can result in decreased vision. Unfortunately, there is no cure. The condition requires long-term treatment under controlled conditions. Blepharitis is often treated with erythromycin ointment, tobradex steroid eye ointment, oral tetracyclines and oral antibiotics. Extreme cases may also need surgical care.
In the more severe cases of all the bacterial eye infections, corticosteroids may also be prescribed. However, the use of steroid treatments is limited due to the negative side effects of long-term use.
How to Prevent a Bacterial Eye Infection
A bacterial eye infection occurs when harmful microorganisms invade the clear front surface of the eye (the cornea) and the thin, moist membrane lining the outer eye and inner eyelid (the conjunctiva). Prevention of contracting one of the types of infections listed above begins by remaining aware as well as with improving hygiene. Here are a few tips that may help:
- Avoid Contact – If you see a person that may have pink eye avoid contact. Since it is spread through direct contact with the excretions from an infected person, don’t touch them. If you do…
- Wash Your Hands – Whether you come into direct contact or not, wash your hand regularly. In that way you will minimize the likelihood of spreading bacteria to your eyes, eyelids or contact lenses. Use anti-infective sprays and cleaners, especially when in public, day care centers and classrooms. If a family member has a bacterial eye infection…
- Wash Everything They Touch – Towels, bedding, clothing and anything else touched by the infected person must be washed and they should not share anything with family members. The individual also needs to wash their hands frequently.
- Teach – Children need to learn how to tell others are infected, what to do when they suspect someone has an infection, and how to avoid touching their eyes.
- For Contact Lens Wearers – Wash your hands prior to handling your contacts. Don’t sleep while wearing contact lenses even if they are breathable and FDA approved for overnight wear. And always clean, store and replace your contact lenses as instructed.
If You’re Already Infected
- Wash your hands before and after applying eye drops and/or ointments. Also wash towels, washcloths and bedding frequently in hot water and detergent and then wash hands again after handling soiled items.
- Avoid touching and/or rubbing your eyes and don’t use swimming pools.
- Wash away discharge from around the eyes several times per day using a clean, warm, wet washcloth. Use only once, then put it in the laundry.
- Use different eye drop dispensers in infected and uninfected eyes.
- Don’t wear contact lenses while infected.
- Clean eyeglasses being careful to discard wipes.
- Don’t share personal items.
A Word of Ending
Worried you may be having a bacterial eye infection? Then you should definitely make an appointment for an eye exam. While our guide offers the most important facts to remember when dealing with either of these five types of eye infections, self-diagnosing your condition often delays proper treatment. Visit your eye doctor as soon as possible to prevent possible harm to your sight.