Kératites stromales amibiennes : épidémiologie et facteurs pronostiques

Purpose: Early treatment of amebic stromal keratitis can change patients' final visual and esthetic prognosis. The aim of this study was to review all proven Acanthamoeba stromal keratitis cases presenting at our ophthalmology emergency department over the past 3 years, in order to delineate the incidence and the factors still leading to this serious complication. Patients and methods: All cases of Acanthamoeba stromal keratitis confirmed with a parasitology examination and treated between January 2000 and December 2002 were recorded. During this period of time, eight patients were identified with this condition. Their charts, as well as biomicroscopic, therapeutic, and outcome data were analyzed. Results: All patients were referred in a second or third intention. Only one patient did not usually wear contact lenses. Six patients had an associated bacterial abscess. The typical amebic annular infiltrate was only observed in one patient. Three patients received an effective anti-amebic treatment in the 15 days following the first symptoms and five patients 1 month or more after. An emergency keratoplasty was carried out in one patient. Finally, visual acuity was lower than 5/10 in all cases. The patients treated in the first 15 days had the best final visual acuity. Discussion: Soft contact lenses are still responsible for the majority of serious amebic corneal complications. Late diagnosis remains the main cause of Acanthamoeba stromal keratitis development, particularly in the absence of contact lens history, because of the delay in treatment. Conclusion: The catastrophic consequences of this complication justify a systematic treatment against ameba in each case of suspected diagnosis. An early and effective treatment of the stromal amebic keratitis can increase the final visual prognosis.