Keratitis

Keratitis is an eye condition characterized by inflammation of the cornea. The cornea is the clear, dome-shaped tissue on the front of the eye that covers the pupil and iris.

Keratitis could be infectious or non-infectious.

Infectious keratitis is the result of a bacterial, viral, fungal or parasitic infection, whereas non-infectious keratitis can be caused due to a minor injury which can occur sue to prolonged use of contact lenses or due to other non-infectious disease. If any sign or symptoms of the disease appear, one must consult the doctor at the earliest.

In case of a severe infection keratitis can lead to serious complications that may permanently damage patient’s vision. But with prompt attention and in mild to moderate cases of keratitis one can effectively recover without the loss of vision.

Signs and symptoms of keratitis include: 

• Irritation and Eye redness
• Eye pain
• Excess tears or other discharge from eye
• Difficulty opening your eyelid because of pain or irritation
• Sudden blurred or decreased vision
• Increased sensitivity to light (photophobia) and
• A feeling of having something in the eye 

If you notice any of the signs or symptoms of keratitis, make an appointment to see your doctor right away. Delays in diagnosis and treatment of keratitis can lead to serious complications, including vision loss.

Causes of keratitis include:

• Eye Injury: injury to the cornea due to a scratch by an object or by penetration of an object can result in the incidence of non-infectious keratitis. Additionally, an injury may allow the bacteria or the fungi to gain access to the cornea through the damaged surface, causing infectious keratitis. 

• Contaminated contact lenses: Bacteria, fungi or parasites, particularly the microscopic parasite Acanthamoeba, may inhabit the surface of a contact lens or contact lens carrying case. So, the cornea may become contaminated by wearing contaminated lens in the eye and can result in infectious keratitis. 

• Viral infection: Some viruses like herpes viruses may also be responsible for causing keratitis. 

• Contaminated water: Use of water contaminated with chemicals such as those used in swimming pools may irritate the cornea and weaken its delicate surface tissue which may result in chemical keratitis. This is usually short-lived and may last only minutes to hours. 

• Bacteria, fungi and parasites in water particularly in oceans, rivers, lakes and hot tubs can enter your eyes when you're swimming or bathing and can result in infectious keratitis especially if the person has an eye injury.

Consult your doctor at the earliest as any sign or symptom of Keratitis appears to receive a diagnosis. Depending on the type and severity of your symptoms, the doctor may refer you to an eye specialist (ophthalmologist) after an initial exam. Your doctor will review your medical history and your symptoms, conduct an eye examination, and perform tests to diagnose keratitis. Diagnosing keratitis typically involves the following:

• Eye Examination: Your doctor will perform a general examination of your eye.  The exam will include an effort to determine how well you can see (visual acuity), usually using standard eye chart
• Penlight exam: Your doctor may examine your eye using a penlight, to check your pupil's reaction, size, and other factors. Your doctor may apply a stain to the surface of your eye to help identify the extent and character of surface irregularities and ulcers of the cornea. 
• Slit-lamp exam: Your doctor may examine your eyes with a special instrument called a slit lamp, which provides a bright source of light and magnification. This instrument uses an intense line of light to illuminate your cornea, iris, lens, and the space between your iris and cornea. The light allows your doctor to view these structures with high magnification to detect the character, extent and effect of keratitis on other structures of the eye. 
• Laboratory analysis: Your doctor may take a sample of tears or scrape some cells from your cornea for laboratory analysis to determine the cause of keratitis and to help develop a treatment plan for your condition.

If the cause of keratitis incident is a scratch by an object or prolonged contact lens wearing, treatment might not be required.

If the patient has significant tearing and pain, the doctor may prescribe medicine and the use of an eye patch until the condition improves. 

Treatment of Infectious keratitis:

     1.  Bacterial keratitis: Mild bacterial keratitis can be treated with the prescription antibacterial eye drops, but if the infection is moderate to severe, the treatment may involve taking oral antibiotics. 

     2. Fungal keratitis:  Treatment of keratitis caused by fungi typically requires both topical and oral anti-fungal medication. 

     3. Viral keratitis:  If a virus is causing the infection, antiviral eye drops and oral antiviral medications are quite effective, but are not able to eliminate the virus completely. Thus, there are chances of recurrence of the infection.

     4. Acanthamoeba keratitis: Parasitic Keratitis caused by a tiny parasite Acanthamoeba can be difficult to treat.  Use of antibiotic eye drops may be helpful, but limited as some Acanthamoeba infections are resistant to the antibacterial medication. In severe cases, where the infection does not improve with medication or in cases where the infection causes permanent damage to the cornea that significantly impairs vision, the doctor may recommend a cornea transplant.

If you wear contact lenses following below mentioned steps help in preventing the development of keratitis:

• Choose daily wear contacts, and take them out before you go to sleep. 
• Wash, rinse and dry your hands thoroughly before handling your contacts.
• Follow your eye care professional's instructions for taking care of your lenses.
• Use only sterile products that are made specifically for contact lens care. 
• Use lens care products made for the type of lenses you wear.
• Gently rub the lenses during cleaning to enhance the cleaning performance of the contact lens solutions.
• Avoid rough handling that might cause your lenses to become scratched.
• Replace your contact lenses as recommended. Replace your contact lens case every three to six months.
• Discard the solution in the contact lens case each time you disinfect your lenses. Don't "top off" the old solution that's already in the case.
• Don't wear contact lenses when you go swimming. 

Preventing viral outbreaks 

Some forms of viral keratitis, such as keratitis caused by the herpes virus, can't be completely eliminated, but following some preventive measures can belittle the chances of recurrence:

• Avoid touching your eyes, eyelids or the skin around your eyes unless you've thoroughly washed your hands.
• Don't use corticosteroid eye drops unless they have been prescribed by a specialist knowledgeable about viral keratitis under careful monitoring. These drops can increase your risk of developing viral keratitis and, if a viral infection does occur, these drops can make it more severe.
• If you wear contact lenses and have multiple recurrences of viral keratitis discontinue using lenses and discuss with the doctor.

Some factors which increase the risk of keratitis include: 

• Contact lenses: Use of contact lenses increases the risk of both infectious and noninfectious keratitis. The risk typically stems from not disinfecting the lenses properly, wearing contact lenses while swimming, wearing them longer than recommended, or using water or homemade solutions to store and clean lenses. 
• Reduced immunity: Persons with compromised or weak immune system are more prone to getting Keratitis.
• Warm climate: If you live in a warm, humid climate, your risk of keratitis is increased. 
• Plant material: Getting plant material can scratch the corneal epithelium and chemicals from the plant can cause an inflammation, which may then lead to an infection. 
• Corticosteroids: Use of a corticosteroid eye drop to treat an eye disorder can increase your risk of developing infectious keratitis or worsen existing keratitis. 
• Eye injury: If the cornea has been damaged from an injury in the past, you are more vulnerable to developing keratitis.

Potential complications of keratitis include:

• Chronic corneal inflammation 
• Chronic or recurrent viral infections of your cornea 
• Open sores on your cornea (corneal ulcers) 
• Corneal swelling and scarring 
• Temporary or permanent reduction in vision.