Toxocariasis is an infection caused by an intestinal nematode found in dogs and cats (Toxocara canis and Toxocara cati). It typically affects children below 10 years of age, when they ingest contaminated soil or food. The larvae migrate through the vessels of the optic nerve to the vitreous cavity and induce an intense inflammatory reaction. Chronic endophthalmitis (25%), posterior granulomas (25-40%) and peripheral granulomas constitute the main clinical presentations.


Department of Ophtalmology, Centro Hospitalar e Universitário de Coimbra, Portugal.


A case report is presented. Information from the clinical process, patient observation and complementary diagnostic exams were used to describe the case.


Woman, 35 years old, presenting with vision loss of the left eye(OS) lasting more than 2 months. The history revealed contact with dogs. Ophthalmologic examination at presentation consisted of: best corrected visual acuity (BCVA) right eye (RE): 10/10, BCVA LE: 1/10; unremarkable pupillary light reflex, ocular motility, biomicroscopy RE&LE and fundus examination RE. Fundus examination of the LE revealed marked vitritis without retina visualization. Analytical study was performed which revealed eosinophilia and positive toxocariasis serology. Therapy with albendazole and systemic corticosteroids was initiated but the patient did not show significant improvement. Vitreous biopsy and subsequent pars plana vitrectomy were performed. During surgery, we observed a retinal granulomatous lesion superiorly and nasally to the optic disc. Two months later the vision improved to 6/10 and fundus examination of LE did not reveal signs of vitritis and/or retinitis.


Positive serological tests and the appearance of the fundus are enough to confirm toxocariasis diagnosis. Treatment depends on the visual acuity, inflammation degree and macular lesions. Systemic corticosteroids reduce the severity of vitritis and extent of vitreoretinal membranes. The antihelmintics eliminate and prevent the parasite migration, but the nematode’s death is accompanied with increased inflammation. Pars plana vitrectomy is indicated to remove opacified cortical vitreous, membranes, tractions and to treat retinal detachment.