Baylisascaris procyonis is a large ascarid that commonly parasitizes raccoons in North America and Europe.1 It is a common cause of clinical larva migrans in animals and also affects humans, causing either neural larva migrans (NLM) affecting the nervous system and/or ocular larva migrans (OLM) and diffuse unilateral subacute neuroretinitis (DUSN) causing visual impairment.1–3 Animals and humans become infected by ingesting infective eggs from areas or articles contaminated with raccoon feces.1 We diagnosed a young girl with Baylisascaris OLM, from the Borough of the Bronx in New York City. This patient is of particular interest because she had an atypical presentation for Baylisascaris OLM and was positive for anti-B. procyonis antibodies in her vitreous fluid as well as being seropositive in serum. In addition, polymerase chain reaction (PCR) testing of the vitreous fluid was positive for Herpes simplex virus-2 (HSV-2) DNA. The patient had mild improvement in visual acuity after diagnostic and therapeutic vitrectomy and treatment with albendazole and acyclovir.
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