DIAGNOSIS: The diagnosis of ocular toxocariasis cannot be confirmed without actual demonstration of the larva in the human eye. Since it is rarely clinically justifiable to obtain a biopsy specimen, the diagnosis of ocular toxocariasis remains presumptive in most instances.

The clinical diagnosis of ocular toxocariasis is suggested by a history of exposure to puppies and/or pica. Physical examination in most instances is normal. However, the patient should be evaluated for signs and symptoms of VLM. Slit-lamp biomicroscopy and indirect ophthalmoscopy can be used to evaluate for signs of intraocular inflammation, retinal granulomata, or retinal detachment (1).

The diagnosis can be further substantiated by appropriate laboratory tests. Most patients with VLM have leukocytosis and eosinophilia. At the time of ocular toxocariasis, however, the white blood count has usually returned to normal, and there is no hypereosinophilia. The ELISA (enzyme-linked immunosorbent assay) is currently the most sensitive and specific laboratory test for the diagnosis of ocular toxocariasis (1, 2).

Cytologic examination of intraocular fluids can be used to support the clinical diagnosis of ocular toxocariasis. The demonstration of eosinophils in aqueous or vitreous fluid should suggest the diagnosis of ocular toxocariasis (1).

1. Shields JA. Ocular toxocariasis. A review. Surv Ophthalmol 1984; 28:361-81.