Chorioretinitis after keratitis caused by Acanthamoeba: case report and review of the literature.

ABSTRACT

OBJECTIVE: A clinicopathologic study to evaluate the histopathologic features associated with Acanthamoeba keratitis and chorioretinitis. DESIGN: Retrospective observational case report. METHODS: On the basis of the clinical history and histologic appearance, the enucleated eye and native corneal button were examined using hematoxylin-eosin stains and special periodic acid-Schiff and Gomori methenamine silver stains. RESULTS: Results of histologic examination of the cornea and retina showed numerous Acanthamoeba cysts in the cornea stromal layers, the necrotic retina, and preretinal and subretinal spaces. CONCLUSIONS: To the authors' knowledge, this is the first proven histologic case of ipsilateral chorioretinitis secondary to primary chronic keratitis caused by Acanthamoeba. The patient had a 30-month history of recurrent keratitis requiring four penetrating keratoplasties. We believe the chorioretinitis resulted from direct spread of the corneal amebic infection. The spread of the Acanthamoeba may have been facilitated by a combined keratoplasty, extracapsular cataract extraction, and intraocular lens insertion. In both specimens, the native corneal button and the enucleated eye with a corneal transplant, the general pathologists overlooked the presence of Acanthamoeba.