Experts are reminding physicians to be on the lookout for Acanthamoeba keratitis (AK) this summer after a social media influencer shared her experience with the eye infection.

Rachel Prochnow shared photos of her infected eye on Instagram, stating that she believed she contracted the infection from showering while wearing contact lenses.

Rachel Prochnow. Instagram. PSA: DO NOT SHOWER, SWIM, OR HOT TUB IN YOUR CONTACTS. May 23, 2024.

 

 

“I had been wearing contacts since I was 12 and was never told not [to] swim, shower, or hot tub in them. However, [I] hadn’t swam in them or hot tubbed in them at all in the past 9 months-the only place I could’ve gotten it [was] from showering in my contacts in Austin, Texas,” the post reads.

“For 3 months, the most sleep I got at a time was 30 minutes. I had 5 different around the clock drops, that had to be 5 minutes apart. My infection (that turned into a disease) was so bad, I was in danger of losing my eye...I wasn’t able to do any drops myself as I was blind (and have been since June 2023) and in excruciating pain. The pain that comes with Acanthamoeba Keratitis makes giving birth look like a walk in the freaking park. The pain was absolutely unreal. I try not to remember it,” the post continues.

While anyone can develop AK, it is most common in those who wear contact lenses.

Somani SN, Ronquillo Y, Moshirfar M. Acanthamoeba Keratitis. StatPearls. November 23, 2023.

 

Handling, storing, or disinfecting lenses improperly are known risk factors for developing the infection.

History of trauma to the cornea, swimming in contaminated water,  and wearing contact lenses while swimming or showering are also known risk factors.

“Luckily, Acanthamoeba is still a fairly rare infection that we see, so that's why you don't hear of everyone who has showered in contact lenses or swam in a pool with contact lenses…automatically having the infection. But…usually the most common sources are pools or tap water,” Dr. Bert adds.

Reported rates of Acanthamoeba keratitis range from 1 to 33 cases per million contact lens wearers every year.

Somani SN, Ronquillo Y, Moshirfar M. Acanthamoeba Keratitis. StatPearls. November 23, 2023.

 

The significant variation in rates is due to regional differences in contact lens types, differences in the use of diagnostic tests for AK, and differences in water contamination in bodies of water.

In the US, it’s estimated that 85% of AK cases occur in contact lens wearers.

Connelly L, Anijeet D, Alexander CL. A descriptive case of persistent Acanthamoeba keratitis: raising awareness of this complex ocular disease. Access Microbiology. 2020;2(3). 

It is a serious infection that can result in permanent damage and blindness. Treatment is also not easy.

 

 “It is a very difficult-to-treat infection because the way that the Acanthamoeba life cycle is, they can go into a form where they're actually in a double wall cyst. And that allows them to be protected from most of the treatments that we have,” Dr. Bert says.

“[In] the treatments that we have, surprisingly, the drops are similar chemicals to what are used in pool cleaners. So you can imagine that that, too, is not the most pleasant eyedrops to be putting into the eye. Some of the other ones are forms of surgical scrubs that we use when we are preparing to go into surgery. So again, these are very, very toxic substances that are needed in order to kill off the Acanthamoeba.”

One study revealed that nearly half of all AK cases were initially misdiagnosed as herpes simplex keratitis.

Somani SN, Ronquillo Y, Moshirfar M. Acanthamoeba Keratitis. StatPearls. November 23, 2023.

 

But Dr. Bert says it is essential that physicians consider Acanthamoeba keratitis as a possible cause of things like red eyes, eye pain, and blurred vision, especially among those who wear contacts.

“If you hear the history of someone who is a contact lens wearer who had exposure to fresh water, [AK] needs to be on the differential diagnosis. And you want to make sure that you don't overlook it as a possibility…because of how difficult it can be to treat,” Dr. Bert says.