Contact lens keratitis is an infection of the cornea linked to lens wear, most often from bacteria such as Pseudomonas and less often from Acanthamoeba or fungi. Sleeping in lenses, poor lens hygiene and contact with tap or swimming water raise the risk, and it can scar the cornea and threaten vision within days.
Key symptoms
- Eye pain, often more than the redness suggests
- Redness and tearing
- Blurred vision
- Sensitivity to light
- Feeling of something in the eye that persists after removing the lens
What you find on exam
- Visual acuity, often reduced
- Redness concentrated around the cornea (ciliary flush)
- White or gray spot on the cornea with fluorescein uptake over it
- Slit lamp: cells in the anterior chamber or a layer of pus (hypopyon)
- Inspect the lenses and the lens case
Tests
- Corneal scraping for Gram stain and culture, done by an ophthalmologist
- Culture of the lens, lens case and solution
- Special tests for Acanthamoeba or fungi if suspected
Treatment basics
- Remove the lenses and stop wearing them
- Same-day ophthalmology referral
- Frequent fluoroquinolone drops such as moxifloxacin, or fortified antibiotics for large ulcers
- No eye patch and no steroid drops at first
- Teach lens hygiene: no sleeping in lenses, no tap water
Red flags
- Ulcer in the center of the cornea or larger than 1 to 2 mm
- Hypopyon or rapidly worsening vision
- Severe pain out of proportion to the exam, a clue to Acanthamoeba
Practice it in Making Synapses
Making Synapses cases
Related guides
Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.