Dr. Russel Lazarus, July 4, 2021

Keratitis is a serious corneal inflammation that affects up to 20 in 10,000 people, with high risks if soft contact lenses are worn overnight.

What is keratitis?

Keratitis is a common inflammatory eye condition that affects the cornea, usually causing sight-threatening corneal ulcers.

The cornea the clear part of the eye that covers both the iris and the pupil. Keratitis can be caused by an injury to the eye or an eye infection.

The incidence of microbial keratitis ranges from 0.4 to 5.2 per 10,000 person-years for rigid gas-permeable and soft contact lens wearers to >20 per 10,000 person-years for overnight soft contact lens wearers.

One population-based study in California estimated that 71,000 cases of severe microbial keratitis could occur per year in the USA.

No matter what the cause of keratitis is, there are  ways to reduce the risk of suffering the serious consequences of corneal ulcerations. If you do develop keratitis, contact an eye doctor near you, immediately.

Types of keratitis

Depending on the underlying cause, keratitis may be classified as either infectious or noninfectious.

Infectious keratitis

Improper handling of contact lenses is often the reason people develop  infectious keratitis.  The different types of infection include:

  1. Bacteria – Staphylococcus aureus and Pseudomonas aeruginosa are the two most common types of bacteria that cause bacterial keratitis.
  1. Fungi – Fungal keratitis is caused by Fusarium, Candida or Aspergillus. While it is common in those who wear contact lenses, it’s also possible to be exposed to these fungi outdoors.
  1. Parasites – A parasite called Acanthamoeba lives outdoors and may be picked up by walking in a wooded area, swimming in a lake or infected tap water coming in contact your contact lenses. This type of infection is called Acanthamoeba keratitis.
  1. Viruses – Viral keratitis is primarily caused by the herpes simplex virus, which can progress from conjunctivitis to keratitis.

Noninfectious keratitis

Noninfectious causes of keratitis include:

  • wearing your contacts too many hours a day
  • Using extended-wear contacts, especially past their expiration date
  • Wearing your contacts while swimming
  • Exposure to intense sunlight, called photo keratitis
  • Eye injury, such as a scratch
  • Weakened immune system
  • Living in a warm climate, which increases the risk of plant materials damaging your cornea

If you suspect you may have keratitis, contact an eye doctor near you.

SEE RELATED: Corneal Ulcers

Find an eye doctor near you

What are the symptoms of keratitis?

Symptoms of keratitis include:

  • excessive tearing
  • eye discharge
  • inability to open your eye
  • pain and irritation in the affected eye
  • red eyes
  • sensitivity to light
  • vision changes, such as blurriness or inability to see

If left untreated, or if the infection is severe, keratitis can lead to serious complications that may permanently damage your vision.

How can keratitis be treated?

Depending on what is causing your keratitis will determine  how it is  treated. If you have infectious keratitis, you will need to take prescription medications.

Your doctor may prescribe oral medications, eye drops or both. These include:

  • antibiotics for bacterial infections
  • antifungals for fungal infections
  • antivirals for viral infections
  • biocides for parasitic infections

In rare cases, when keratitis doesn’t respond to medication, or if it causes corneal ulcers and possibly permanent damage to the cornea, significantly impairing your vision, your doctor may recommend a cornea transplant.

LEARN MORE:  Guide to Corneal Diseases

Schedule an urgent appointment with an eye doctor near you who can diagnose and treat your keratitis.