Amoebic keratitis in Iran (1997-2007)

Abstract

Background: Amoebic keratitis introduced as a painful corneal infection which sometimes lead to poor vision and blind-ness. The main goal of this study was to report amoebic keratitis during ten years from 1997-2007 in patients who was sus-pected to have amoebic keratitis and referred to Parasitology laboratory, School of Public Health, Tehran Univer¬sity of Medical Sciences, Iran. Other aim was to assess the major risk factor for developing this sight-threatening disease. Comparison of lens culture and corneal scrapes culture also was performed.
Methods: During 1997-2007, 142 patients referred to Dept. of Medical Parasitology, School of Public Health, Tehran Uni-versity of Medical Sciences, Iran. Details of each patient such as age, sex, history of contact lens wear, type of contact lens, clinical symptoms were recorded in questioners. Keratitis was diagnosed on the basis of culture of lenses and/or corneal scrapes on non-nutrient agar overlaid with Escherichia coli and direct microscopy of lenses and/or corneal scrapes.
Results: Among 142 patients, 49 (34.5%) had amoebic keratitis. 73.46% of these patients were from Tehran but there were a few cases from other cities. The commonest age was between 15-25 yr (75.5%) and more female (37:12) were identified then male. It is worth to mention that 44 patients (89.79%) were contact lens wearers who among them 41 patients (93.18%) wore soft contact lens and only three patients suffer from amoebic keratitis because of wearing hard contact lens. Other finding of this study demonstrated that the most common sign of the patients was severe pain combined with photophobia.
Conclusion: This study indicates that Acanthamoeba keratitis continue to rise in Iran. This is due to increase frequency of lens wearers as well as consideration of ophthalmologist to Acanthamoeba as an agent of keratitis and improvement of labo¬ratory methods. Another finding of this research was the confirmation of soft contact lens as a major risk factor. It is rec¬ommended to educate contact lens wearers for regular disinfection. Besides, culture of corneal scrapes was negative in most of cases, so lens culture were performed which had a much better result.