History

Inquire about pets in the home. Ask if children play in a sandbox. Ask about pica and handwashing practices and determine if hygiene practices are poor. Symptoms during the acute phase may include the following:

Abdominal pain
Decreased appetite
Restlessness
Fever
Coughing
Wheezing
Hives
History of seizures
Ocular involvement - Decreased visual acuity, seeing floaters or bubblelike images

Physical

Tenderness in the right upper quadrant or hepatomegaly may be present in patients with liver involvement.

With pulmonary involvement, wheezing may be heard. Breath sounds may be decreased if a pleural effusion is present.

Patients with ocular involvement may present with the following:

Retinal detachment due to traction caused by retinal fibrosis

Funduscopic examination of the right eye of a patient with ocular toxocariasis showing rhegmatogenous retinal detachment.
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Peripapillary inflammation
Peripheral retinal exudates
Gliotic mass in peripheral retina
Vitreoretinal traction band in peripheral retina

Causes

Risk factors for toxocariasis include the following:

Living with or raising dogs and cats
Eating without handwashing
Infection via contact with soil from a yard, sandbox, park, or playground

Complications

Decreased visual acuity may occur if ocular toxocariasis is not identified and treated.

Retinal detachment due to ocular involvement may cause unilateral visual loss.

Seizures may result from cerebral involvement.

Differential Diagnoses

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Media Gallery

The image on the left is a posteroanterior chest radiograph in a patient with toxocariasis. The image on the right is a CT scan of the patient with toxocariasis showing multiple pulmonary nodules with surrounding ground-glass opacities at first visit.
Funduscopic examination of the right eye of a patient with ocular toxocariasis showing rhegmatogenous retinal detachment.
Immunogold finding of Toxocara canis larva reacted with a seropositive human serum. Arrows indicate each particle. (A) High-density immunogold particles are distributed in the large columnlike secretory cell (LCSC), excretory duct (ED), and cuticle(C); (B) high-density immunogold particles are shown in the secretory cell (SC), excretory duct (ED), and cuticle; (C) immunogold particles are distributed in the excretory duct (ED); (D) high-density particles are displayed in the microvilli of the intestine (MI); (E) immunogold particles are shown in the excretory duct; and (F) high-density immunogold particles are distributed in the cuticle(C).