Keratitis: Causes, Symptoms, and Treatment

What is Keratitis?

Keratitis is an inflammation of the cornea, the clear, dome-shaped surface that covers the front of the eye. This condition can be caused by infection, injury, or underlying diseases. Keratitis can lead to pain, blurred vision, and, in severe cases, vision loss if left untreated. The cornea is crucial for focusing vision, so any damage or inflammation can significantly impact your ability to see clearly.

Keratitis can be classified into two main types:

• Infectious keratitis: Caused by bacteria, viruses, fungi, or parasites.
• Non-infectious keratitis: Resulting from injuries, underlying diseases, or prolonged use of contact lenses.

Source: Mayo Clinic, National Eye Institute (NIH)

Common Causes

Keratitis can arise from various causes, including infections, injuries, and underlying health conditions. Here are some of the most common causes:

• Bacterial infections: Often due to Staphylococcus or Pseudomonas bacteria, which can enter the eye through contact lens use, injuries, or contaminated water.
• Viral infections: Herpes simplex virus (HSV) and varicella-zoster virus (the virus that causes chickenpox and shingles) are common culprits.
• Fungal infections: Typically caused by Fusarium, Aspergillus, or Candida species. These infections are more common in warm climates or after eye injuries involving plant material.
• Parasitic infections: Acanthamoeba keratitis is a severe infection often linked to poor contact lens hygiene or swimming while wearing contacts.
• Contact lens wear: Prolonged or improper use of contact lenses can lead to corneal irritation, infections, and oxygen deprivation to the cornea.
• Eye injuries: Scratches, foreign objects, or chemical burns can damage the cornea and lead to inflammation or infection.
• Dry eye syndrome: Chronic dryness can irritate the cornea and make it more susceptible to infections.
• Autoimmune diseases: Conditions like rheumatoid arthritis or Sjogren's syndrome can cause inflammation in the cornea.
• Allergies: Severe allergic reactions can lead to corneal inflammation.
• Exposure to UV light: Prolonged exposure to sunlight or artificial UV light (e.g., tanning beds) can cause photokeratitis, a type of corneal sunburn.

Source: Centers for Disease Control and Prevention (CDC), American Academy of Ophthalmology

Associated Symptoms

Keratitis can cause a range of symptoms that affect your vision and comfort. Common symptoms include:

• Eye redness
• Eye pain or discomfort, often described as a gritty or burning sensation
• Excessive tearing or discharge from the eye
• Blurred or decreased vision
• Sensitivity to light (photophobia)
• Difficulty opening the eyelid due to pain or irritation
• A feeling that something is in your eye
• White patches or cloudiness on the cornea (in advanced cases)

If you experience any of these symptoms, especially if they worsen or persist, seek medical attention promptly to prevent complications.

Source: World Health Organization (WHO), Cleveland Clinic

When to See a Doctor

It's essential to see a healthcare provider if you experience any symptoms of keratitis, especially if they persist or worsen. Early diagnosis and treatment can prevent complications like corneal ulcers, scarring, or vision loss. Schedule an appointment with an eye specialist (ophthalmologist) if you notice:

• Persistent eye pain or discomfort
• Worsening redness or swelling
• Increased sensitivity to light
• Blurred vision that doesn’t improve
• Discharge or excessive tearing from the eye
• A feeling of something being stuck in your eye

If you wear contact lenses and experience any of these symptoms, remove your lenses immediately and avoid wearing them until you’ve seen a doctor.

Diagnosis

Diagnosing keratitis typically involves a comprehensive eye examination. Your doctor may perform the following tests and procedures:

• Slit-lamp examination: A specialized microscope is used to examine the cornea, iris, lens, and other structures of the eye in detail.
• Eye culture: A sample of tears or discharge may be taken to identify the specific bacteria, virus, fungus, or parasite causing the infection.
• Corneal scraping: In some cases, a small sample of corneal tissue may be collected for laboratory analysis.
• Fluorescein stain: A dye is applied to the eye to highlight corneal abrasions or ulcers under a special light.
• Blood tests: These may be ordered if an underlying autoimmune condition is suspected.

Your doctor will also ask about your medical history, recent eye injuries, contact lens use, and any exposure to potential irritants or infectious agents.

Source: National Eye Institute (NIH)

Treatment Options

The treatment for keratitis depends on the underlying cause and severity of the condition. Here are the most common treatment approaches:

Medical Treatments

• Antibacterial eye drops or ointments: Used to treat bacterial keratitis. Common medications include fluoroquinolones (e.g., ofloxacin, ciprofloxacin) or cephalosporins.
• Antiviral medications: For viral keratitis, especially herpes simplex keratitis, antiviral eye drops (e.g., trifluridine), oral antivirals (e.g., acyclovir, valacyclovir), or ointments may be prescribed.
• Antifungal medications: Fungal keratitis is treated with antifungal eye drops (e.g., natamycin) or oral medications (e.g., fluconazole, itraconazole).
• Antiparasitic medications: Acanthamoeba keratitis may require antiparasitic eye drops (e.g., polyhexamethylene biguanide) or oral medications.
• Steroid eye drops: In some cases, corticosteroids may be used to reduce inflammation, but they are typically prescribed with caution to avoid worsening infections.
• Pain relief: Over-the-counter pain relievers (e.g., ibuprofen, acetaminophen) or prescription medications may be recommended to manage discomfort.

Home and Supportive Treatments

• Cold compresses: Applying a cold, damp washcloth to your closed eyelid can help reduce discomfort and swelling.
• Avoiding contact lenses: Do not wear contact lenses until your doctor confirms it is safe to do so.
• Protecting your eyes: Wear sunglasses to reduce light sensitivity and avoid rubbing your eyes.
• Artificial tears: Lubricating eye drops can help relieve dryness and irritation.
• Good hygiene: Wash your hands frequently and avoid touching your eyes to prevent further irritation or infection.

In severe cases, hospitalization or surgical intervention (e.g., corneal transplant) may be necessary, especially if there is significant corneal damage or vision loss.

Source: Mayo Clinic, American Academy of Ophthalmology

Prevention Tips

While not all cases of keratitis can be prevented, you can take steps to reduce your risk:

• Practice good contact lens hygiene:
  • Wash your hands thoroughly before handling contact lenses.
  • Follow your doctor’s instructions for cleaning, disinfecting, and storing lenses.
  • Avoid sleeping in contact lenses unless they are specifically designed for extended wear.
  • Replace contact lenses as recommended (e.g., daily, weekly, or monthly).
  • Avoid swimming or showering while wearing contact lenses.
• Protect your eyes from injury:
  • Wear safety goggles when working with tools, chemicals, or in environments with airborne debris.
  • Avoid rubbing your eyes, especially with dirty hands.
• Manage underlying conditions:
  • If you have dry eye syndrome, use artificial tears or prescribed medications to keep your eyes lubricated.
  • Control autoimmune conditions with the help of your healthcare provider.
• Avoid exposure to UV light:
  • Wear UV-protective sunglasses when outdoors, even on cloudy days.
  • Avoid tanning beds and other sources of artificial UV light.
• Practice good overall hygiene:
  • Avoid sharing eye makeup, towels, or other personal items that may spread infection.
  • Replace eye makeup regularly, especially after an eye infection.

Source: Centers for Disease Control and Prevention (CDC)

Emergency Warning Signs

Seek immediate medical attention if you experience any of the following symptoms, as they may indicate a severe or sight-threatening condition:

• Sudden vision loss or severe blurred vision: This could indicate significant corneal damage or other serious eye conditions.
• Severe eye pain: Intense pain may signal a corneal ulcer or other complications.
• White or cloudy spot on the cornea: This could be a sign of a corneal ulcer or infection spreading.
• Inability to open the eye: Severe swelling or pain may prevent you from opening your eyelid.
• Signs of systemic infection: Fever, chills, or severe headache accompanying eye symptoms may indicate a spreading infection.
• Eye injury with foreign object: If you have a foreign object stuck in your eye or a chemical burn, seek emergency care immediately.

If you experience any of these emergency warning signs, go to the nearest emergency room or call emergency services. Delaying treatment can lead to permanent vision loss or other serious complications.

Source: World Health Organization (WHO), Cleveland Clinic