For a week Nick Humphreys’ right eye felt dry and irritated. He tried treating it with over-the-counter eye drops and muting the brightness on his devices. Still, his pain increased. He finally visited a local hospital and learned that he had a parasitic infection, Acanthamoeba keratitis (AK), which he likely developed after showering while wearing his contact lenses. He lost vision in his right eye and in August he will undergo a cornea transplant to restore his sight.
“If I’d had the slightest idea that this was even a remote possibility I would never have worn contacts in the first place. It’s crucial that people out there know this is a reality and can happen because of something as simple as showering,” Humphreys, 29, of Shropshire, England shared in an article he wrote for the Shropshire Star.
Humphreys first started having problems with his eye in January 2018. After going to the doctor, he took eye drops for a week, but the pain didn’t improve and he still grappled with an infection. By March, he lost the sight in his eye, a rare but real complication of a serious infection on the cornea.
“Most of the infections can be treated aggressively with drops,” Dr. Danielle Trief, an assistant professor of ophthalmology at the Edward S. Harkness Eye Institute at Columbia University Medical Center in New York, who did not treat Humphreys, told TODAY. “It is unusual to lose total vision.”
But that's not to say it's harmless.
"It's as bad of a corneal infection as you can get," Dr. Randy McLaughlin, an associate professor in the optometry division at the Ohio State University Wexner Medical Center in Columbus, told TODAY. "It can form like a cyst that makes it harder to treat."
AK is protozoan parasite that thrives in warm, moist dark areas. It’s found in pools and hot tubs, though, Trief has also treated patients who developed it from showering (it’s more commonly found in well water). While not all people who develop AK wear contact lenses, it’s rarely found in non-contact lens users.
“I’m always surprised to see Acanthamoeba in someone without contact lens,” she said.
The reason it’s more common in contact wearers is because the contacts create tiny cuts on the eye that make it easier for the parasite to ooze in and become trapped under the lens.
“You can get little micro-abrasions on the cornea and if there is a bacteria or parasite in the water it gets in. Normally, the Acanthamoeba wouldn’t penetrate the eye. (But) it can get trapped in there,” Trief said.
The parasite causes ulcers and scarring on the cornea and if they become too severe a person can lose vision, like Humphreys. If that’s the case, doctors can perform a corneal transplant, an outpatient procedure where doctors replace the damaged cornea with a deceased donor cornea. The surgery takes about an hour and doctors put patients under anesthesia and numb the eye. Sixteen fine stitches hold the cornea in place and over a few weeks, doctors slowly remove them. But people who have transplants rarely have perfect vision in that eye and are at higher risk of glaucoma and rejection of the cornea.
“I would not wish that infection on anyone,” Trief said.
The easiest way to avoid Humphreys' fate? Never shower or swim in contact lenses.
"If you don’t wear contact lenses (in the shower or swimming) you are greatly greatly going to eliminate the risk," McLaughlin.
He also recommends that patients experiencing eye pain for more than a few minutes make an appointment with an eye doctor.
"If the pain doesn’t go away within several minutes or a half hour and is persistent you should get it checked," he said. "If you get Acanthamoeba and it is not treated you can you have a long road ahead."
Other tips for safe contact lens usage include:
- No sleeping in contacts.
- Only wear them for the duration prescribed — dailies only once, weeklies only for seven days, etc.
- Wash your hands before putting them in and taking them out.
- If a lens is irritating your eye, take it out immediately.
- Less is more: Try wearing them for eight hours or less.
- If your contact lenses don’t feel right, visit a doctor for a better fitting lens.
“The more we abuse our eyes the less likely we will be able to wear contact lenses into our 50s and 60s,” Trief said.