Early Diagnose Acanthamoeba keratitis by Polymerase Chain Reaction (PCR)

Abstract

Abstract: : Purpose:Acanthamoeba keratitis is a recalcitrant disease. Empirical diagnosis may not be easy especially in the early stage. Early diagnose and treatment is helpful to patients; and polymerase chain reaction (PCR) may effectively detect Acanthamoeba genome in the early stage of corneal ulcers. Methods:Corneal epithelial specimens were collected from patients suspected with Acanthamoeba keratitis. Specimens were used for culture and PCR detecting Acanthamoeba ribosomal DNA. Clinical course and outcome of the patients were reviewed. Results:Ten patients were positive for Acanthamoeba PCR, and received PHMB treatment subsequently. Among them the diagnosis was reconfirmed by positive culture result in six patients. In three of them, the diagnosis was made early when there were only corneal epithelial erosions. These three patients preserved better vision than the others. Conclusions:Compared to routine smear and culture techniques, PCR for Acanthamoeba can be a sensitive and rapid method for early diagnosis, and it also helps to differentiate pathogens with similar clinical presentation.

Keywords: Acanthamoeba • keratitis • clinical laboratory testing