Refractory atypical corneal lesions with or without extension onto the conjunctiva responding to Acanthamoeba treatment

Abstract

AbstractPurposeAcanthamoeba keratitis (AK) is a sight‐threatening infection classically linked to contact lens wear. Starting as a non‐specific unilateral epithelial irregularity like punctate or pseudo‐dendritic lesions, AK can evolve to a ring‐shaped stromal infiltrate with risk of corneal melting. Radial keratoneuritis may appear. Diagnosis relies on protozoan identification by culture with direct exam and PCR analysis. Acanthamoeba can also be demonstrated by in vivo confocal microscopy (IVCM). Early phase AK is treated with a combination of topical amoebicides. We report three atypical cases of suspected AK.MethodsRetrospective report of three women with unilateral atypical corneal lesions, two of them extending to the conjunctiva. Slit lamp photographs, corneal oct and confocal microscopy will be presented.ResultsThree patients, two women in their thirties and one in her sixties, consulted for chronic ocular discomfort unsuccessfully treated by topical antibiotics and corticosteroids for months to years. No history of contact lens wear or water exposure was reported. Two had visual acuity (VA) at 20/20 and one a variable VA for 4 years. Slit lamp examination showed an atypical superficial well delimitated linear lesion across cornea and conjunctiva. In all patients, successive examinations had revealed a moving and migrating character of the refractory lesions to topical antibiotics and corticosteroids. All had a rapid response to Polyhexamethylenebiguanide (PHMB) and propamidine (Brolene) and healed without stromal opacification in a few weeks. Although corneal scrapping cultures remained negative, two of them realized an IVCM with signs of AK and all responded rapidly and completely to amoebicide drops supporting the diagnosis of AK.ConclusionsThese cases show a particularly atypical involvement of corneal and conjunctival refractory lesions responding very well to PHMB and Brolene suggesting an AK origin.