Contact lens-associated Acanthamoeba keratitis: a report from the USA.

Acanthamoeba keratitis is a serious complication of contact lens wear. The majority of reports documented in the literature are from the USA. The typical features of this condition are reported and illustrated by personal observations. Clinically, Acanthamoeba keratitis can be misdiagnosed as viral, especially Herpes simplex, fungal, or bacterial keratitis. Culture and microscopic examination of corneal scrapings, biopsy, or of the disc obtained at keratoplasty, and special staining techniques, including indirect immunofluorescence, can provide the definitive diagnosis. We discuss the medical and surgical management of this disease, as well as the risk factors and preventive measures. Knowledge of the factors which are responsible for the low incidence of contact lens-associated Acanthamoeba keratitis in Europe, would be helpful in understanding the epidemiology of this disease.