Ophthalmology referral was made the following morning due to impaired visual acuity and severity of pain, and a slit lamp exam was conducted. He was placed on antibiotic and steroid drops for presumed conjunctivitis. His symptoms continued, and he was started on treatment for presumed herpes keratitis on day 5 after presentation. By day 13 he had no substantial improvement and was seen by a corneal specialist. At this visit it was revealed that he had used tap water in his contact lens carrying case. Exam showed dendritic keratitis Case Photo #1 as well as what was thought to be early radial keratoneuritis Case Photo #2 periphery hyperpigmentation. These features were consistent with findings of parasitic infection. Corneal scrapings were obtained at that time and sent for bacterial, viral, and parasitic cultures. On day 18 the cultures became positive for acanthamoeba histolytica. He was started on treatment 2 days later.
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