Acanthamoeba Keratitis During Orthokeratology.

Infection is a serious adverse reaction of contact lenses, and its risk increases with continuous wear. Ulcerative keratitis has complicated orthokeratology in which a contact lens is worn to mold the cornea. Many reported cases of microbial keratitis associated with orthokeratology are caused by Pseudomonas aeruginosa, but Acanthamoeba is becoming recognized as a prevalent cause. I report a culture-confirmed case to highlight this emerging problem.

DISCUSSION

Orthokeratology reshapes the cornea by programed fitting of rigid gas-permeable contact lenses that may involve overnight lens wear. Bacterial keratitis is the most common infectious complication. However, several patients, mostly teenagers, have developed amoebic keratitis during orthokeratology.

Acanthamoeba keratitis is an emerging problem of orthokeratology that largely affects younger contact lens wearers. Rigid lenses are associated with Acanthamoeba keratitis, but Acanthamoeba keratitis occurs more often with soft than with hard lenses. The risk of ulcerative keratitis with rigid gas-permeable contact lenses is greater when they are worn overnight, but why the spectrum of microorganisms infecting patients undergoing orthokeratology might differ from that of other rigid contact lens wearers is unclear.

Eye-care practitioners commented 25 years ago that “orthokeratology remains experimental” and should “not be practiced on children until it has undergone appropriate clinical trials.” The practice of orthokeratology has evolved and grown, but definitive studies are still needed to determine the incidence and predisposing factors of infectious complications. Warning patients and parents about vision-threatening complications should be part of contact lens fitting.

Results:

A 16-year-old girl developed laboratory-confirmed acanthamoebic keratitis during orthokeratology for myopic reduction. Recent case reports suggest that Acanthamoeba is a cause of microbial keratitis associated with gas-permeable contact lenses among teenagers and young adults undergoing orthokeratology.

Conclusions:

Acanthamoeba keratitis is an emerging complication of orthokeratology in young myopes.