Wills ophthalmologists see alarming increase in rate of Acanthamoeba keratitis

Chicago-Ophthalmologists at Wills Eye Hospital, Philadelphia, have seen a recent dramatic increase in cases of Acanthamoeba keratitis.

Speaking at the annual meeting of the American Academy of Ophthalmology, Fabiano N. Rocha, MD, reported this infection was seen in 19 patients between January 2004 and August 2005.

All 19 patients had a history of frequent replacement contact lens wear and were using multipurpose solutions for lens care. In 42% of patients there was a history of exposure to well water, while 26% reported swimming without removing their lenses.

At the time of presentation to Wills Eye Hospital, nearly three-fourths of the patients had been misdiagnosed with herpex simplex virus keratitis and had received steroids.

Upon diagnosis of Acanthamoeba keratitis, all of the patients received combined therapy with topical antiamoebic drugs. Among 9 patients who completed their antiamoebic therapy, best corrected visual acuity was 20/30 or better in seven and count fingers to hand motion in the other two. Overall, visual outcomes were better in patients who presented with epithelial radial keratitis compared with those who had a ring ulcer or stromal disease at the time of presentation.

“We are concerned about this recent increase in cases of Acanthamoeba keratitis in patients using frequent replacement contact lenses and multipurpose solutions and believe our experience underlines the importance of maintaining a high index of suspicion for this infection since early diagnosis is important to improve prognosis,” said Dr. Rocha.