What Is Keratitis and Why Does It Occur?

Keratitis refers to inflammation of the cornea, the transparent front part of your eye that covers the iris, pupil, and anterior chamber. This condition can develop from various causes and may affect one or both eyes. The cornea plays a crucial role in focusing light that enters your eye, making any inflammation potentially serious for your vision.

The causes of keratitis fall into two main categories: infectious and non-infectious. Infectious keratitis results from bacteria, viruses, fungi, or parasites invading the corneal tissue. Non-infectious keratitis can stem from eye injuries, wearing contact lenses for too long, exposure to intense ultraviolet light, or underlying inflammatory conditions that affect the eye. People with weakened immune systems may face higher risks of developing keratitis, especially the infectious types.

Common Symptoms of Keratitis

Recognizing the symptoms of keratitis early can make a significant difference in treatment outcomes. The most common signs include:

  • Eye pain - Often described as moderate to severe
  • Redness - Particularly around the cornea
  • Excessive tearing - Your eye may produce more tears than usual
  • Blurred or decreased vision - Vision changes can occur rapidly
  • Light sensitivity - Discomfort when exposed to bright light
  • Sensation of something in your eye - A persistent foreign body sensation
  • Difficulty opening your eyelid - Due to pain or swelling

These symptoms can develop quickly, especially with infectious keratitis. The severity often depends on the cause and how long the condition has been present. If you experience any of these symptoms, seeking prompt medical attention is essential to prevent potential complications that could permanently affect your vision.

Types of Keratitis and Their Specific Causes

Different types of keratitis have distinct causes and may present with varying symptoms and progression patterns:

Bacterial Keratitis: Often associated with contact lens wear, especially improper cleaning or overnight use. Common bacteria include Staphylococcus aureus, Streptococcus pneumoniae, and Pseudomonas aeruginosa. According to the American Academy of Ophthalmology, bacterial keratitis can progress rapidly and requires immediate treatment.

Viral Keratitis: Herpes simplex virus is a leading cause, with the National Eye Institute reporting that once infected, the virus remains dormant in the body and can reactivate, causing recurrent episodes. Herpes zoster (shingles) can also cause keratitis when it affects the ophthalmic nerve.

Fungal Keratitis: More common in warm, humid climates and often follows corneal injury involving plant material. The Centers for Disease Control and Prevention notes that fungal keratitis can be difficult to treat and may require prolonged therapy.

Acanthamoeba Keratitis: Caused by a microscopic parasite found in water, this rare but serious infection is most common among contact lens wearers who use homemade solutions or swim while wearing lenses.

Non-infectious Keratitis: Can result from dry eye syndrome, exposure to ultraviolet light (photokeratitis), or physical or chemical injuries to the cornea. Autoimmune conditions like rheumatoid arthritis can also trigger corneal inflammation.

Risk Factors and Prevention Strategies

Certain factors can increase your risk of developing keratitis. Being aware of these risk factors and taking preventive measures can significantly reduce your chances of experiencing this painful condition:

Contact Lens Use: Contact lens wearers have a higher risk of developing keratitis, particularly if they:

  • Wear lenses longer than recommended
  • Don't clean lenses properly
  • Use homemade or expired cleaning solutions
  • Sleep with contact lenses in
  • Swim or shower while wearing lenses

According to Bausch + Lomb, following proper lens care protocols can dramatically reduce infection risks. This includes washing hands before handling lenses and replacing storage cases regularly.

Prevention Strategies: Protecting your eyes is essential for preventing keratitis. Recommended practices include:

  • Wearing protective eyewear during activities that risk eye injury
  • Using sunglasses that block UV light when outdoors
  • Avoiding sharing eye makeup or towels
  • Properly treating eye conditions like dry eye
  • Getting regular eye examinations

For contact lens wearers, Acuvue recommends following a strict cleaning regimen and replacing lenses according to your eye care professional's schedule. Daily disposable lenses may be a safer option for those prone to eye infections.

Diagnosis and Treatment Approaches

When keratitis is suspected, prompt medical evaluation is crucial. Eye care professionals typically diagnose keratitis through:

  • Comprehensive eye examination
  • Slit-lamp evaluation to examine the cornea in detail
  • Corneal scraping for laboratory analysis in suspected infectious cases
  • In some cases, confocal microscopy to identify specific pathogens

Treatment varies based on the type and severity of keratitis. Alcon, a leader in eye care products, provides various medications used in keratitis treatment. Common approaches include:

For Bacterial Keratitis: Antibiotic eye drops or ointments, often administered frequently at first (every 15-30 minutes in severe cases). These may include fluoroquinolones or aminoglycosides.

For Viral Keratitis: Antiviral medications such as acyclovir or ganciclovir, available as eye drops, oral medications, or both. Pfizer produces several antiviral medications used in treating ocular herpes infections.

For Fungal Keratitis: Antifungal eye drops like natamycin or voriconazole. Treatment often continues for weeks or months.

For Acanthamoeba Keratitis: Combination therapy with biguanides and diamidines, requiring prolonged treatment.

For Non-infectious Keratitis: Treating the underlying cause, which may include artificial tears for dry eye, corticosteroid drops for inflammation (used cautiously), or addressing autoimmune conditions.

In severe cases that don't respond to medication, corneal transplantation may be necessary. Recovery time varies widely depending on the cause, severity, and individual response to treatment. Regular follow-up appointments are essential to monitor healing and adjust treatment as needed.

Conclusion

Keratitis represents a significant threat to eye health that requires awareness and prompt action. By understanding its causes—from infectious agents to contact lens complications—and recognizing symptoms early, you can seek timely treatment and protect your vision. Prevention remains the best approach, particularly for contact lens wearers who should adhere strictly to proper hygiene and usage guidelines. If you experience eye pain, redness, vision changes, or sensitivity to light, consult an eye care professional immediately. With proper diagnosis and treatment, most cases of keratitis can be effectively managed, preserving your eye health and visual function for years to come. Remember that advances in eye care continue to improve treatment options, making even severe cases more manageable than in the past.

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This content was written by AI and reviewed by a human for quality and compliance.